From c53586a65cc7104ff2a9d2c0c36033c40faa7fde Mon Sep 17 00:00:00 2001
From: kenjis <kenji.uui@gmail.com>
Date: Sat, 23 Sep 2023 21:11:25 +0900
Subject: [PATCH 01/21] chore: change for upgrade to PHP 8.0

---
 rector.php | 20 +++++++++++++++++++-
 1 file changed, 19 insertions(+), 1 deletion(-)

diff --git a/rector.php b/rector.php
index 1eaacd12328b..2b928390fca9 100644
--- a/rector.php
+++ b/rector.php
@@ -37,6 +37,13 @@
 use Rector\Php55\Rector\String_\StringClassNameToClassConstantRector;
 use Rector\Php70\Rector\FuncCall\RandomFunctionRector;
 use Rector\Php73\Rector\FuncCall\JsonThrowOnErrorRector;
+use Rector\Php80\Rector\Class_\AnnotationToAttributeRector;
+use Rector\Php80\Rector\Class_\ClassPropertyAssignToConstructorPromotionRector;
+use Rector\Php80\Rector\FunctionLike\MixedTypeRector;
+use Rector\PHPUnit\AnnotationsToAttributes\Rector\Class_\AnnotationWithValueToAttributeRector;
+use Rector\PHPUnit\AnnotationsToAttributes\Rector\Class_\CoversAnnotationWithValueToAttributeRector;
+use Rector\PHPUnit\AnnotationsToAttributes\Rector\ClassMethod\DataProviderAnnotationToAttributeRector;
+use Rector\PHPUnit\AnnotationsToAttributes\Rector\ClassMethod\DependsAnnotationWithValueToAttributeRector;
 use Rector\PHPUnit\CodeQuality\Rector\Class_\YieldDataProviderRector;
 use Rector\PHPUnit\Set\PHPUnitSetList;
 use Rector\Privatization\Rector\Property\PrivatizeFinalClassPropertyRector;
@@ -50,7 +57,7 @@
 return static function (RectorConfig $rectorConfig): void {
     $rectorConfig->sets([
         SetList::DEAD_CODE,
-        LevelSetList::UP_TO_PHP_74,
+        LevelSetList::UP_TO_PHP_80,
         PHPUnitSetList::PHPUNIT_CODE_QUALITY,
         PHPUnitSetList::PHPUNIT_100,
     ]);
@@ -110,6 +117,17 @@
         RandomFunctionRector::class,
 
         SimplifyRegexPatternRector::class,
+
+        // PHP 8.0 features but cause breaking changes
+        ClassPropertyAssignToConstructorPromotionRector::class,
+        MixedTypeRector::class,
+
+        // PHPUnit 10 (requires PHP 8.1) features
+        DataProviderAnnotationToAttributeRector::class,
+        DependsAnnotationWithValueToAttributeRector::class,
+        AnnotationWithValueToAttributeRector::class,
+        AnnotationToAttributeRector::class,
+        CoversAnnotationWithValueToAttributeRector::class,
     ]);
 
     // auto import fully qualified class names

From 7622d1dc9120f122eff5b3eb30e4c28d36f082c9 Mon Sep 17 00:00:00 2001
From: kenjis <kenji.uui@gmail.com>
Date: Sun, 24 Sep 2023 05:28:48 +0900
Subject: [PATCH 02/21] refactor: upgrade to PHP 8.0 by rector

---
 app/Views/errors/cli/error_exception.php      | 21 ++----
 app/Views/errors/html/error_exception.php     |  2 +-
 system/Autoloader/Autoloader.php              |  6 +-
 system/Autoloader/FileLocator.php             | 10 +--
 system/BaseModel.php                          | 40 ++++------
 system/CLI/CLI.php                            |  2 +-
 system/CLI/Commands.php                       |  2 +-
 system/CLI/GeneratorTrait.php                 |  2 +-
 system/Cache/Handlers/PredisHandler.php       | 21 ++----
 system/Cache/Handlers/RedisHandler.php        | 21 ++----
 system/CodeIgniter.php                        |  4 +-
 system/Commands/Database/CreateDatabase.php   |  2 +-
 system/Commands/Encryption/GenerateKey.php    |  2 +-
 system/Commands/Utilities/Publish.php         |  4 +-
 .../ControllerMethodReader.php                |  2 +-
 .../Utilities/Routes/FilterFinder.php         |  4 +-
 system/Common.php                             | 64 ++++++----------
 system/ComposerScripts.php                    |  2 +-
 system/Config/BaseConfig.php                  |  4 +-
 system/Config/DotEnv.php                      |  8 +-
 system/Config/Factories.php                   |  8 +-
 system/Cookie/Cookie.php                      | 15 ++--
 system/Cookie/CookieStore.php                 |  2 +-
 system/Database/BaseBuilder.php               | 20 ++---
 system/Database/BaseConnection.php            | 16 ++--
 system/Database/Database.php                  |  4 +-
 system/Database/Forge.php                     |  4 +-
 system/Database/MigrationRunner.php           |  2 +-
 system/Database/OCI8/Connection.php           | 12 +--
 system/Database/OCI8/Forge.php                |  4 +-
 system/Database/Postgre/Connection.php        |  6 +-
 system/Database/Query.php                     |  4 +-
 system/Database/RawSql.php                    |  4 +-
 system/Database/SQLSRV/Builder.php            |  6 +-
 system/Database/SQLSRV/Connection.php         |  6 +-
 system/Database/SQLite3/Connection.php        |  2 +-
 system/Database/SQLite3/Forge.php             |  2 +-
 system/Database/SQLite3/Table.php             |  2 +-
 system/Database/Seeder.php                    |  2 +-
 system/Debug/BaseExceptionHandler.php         |  8 +-
 system/Debug/ExceptionHandler.php             |  4 +-
 system/Debug/Exceptions.php                   | 63 +++++-----------
 system/Debug/Toolbar.php                      |  4 +-
 system/Debug/Toolbar/Collectors/Database.php  |  2 +-
 system/Debug/Toolbar/Collectors/Files.php     |  2 +-
 system/Debug/Toolbar/Collectors/Routes.php    |  2 +-
 system/Email/Email.php                        | 22 +++---
 system/Entity/Cast/ArrayCast.php              |  2 +-
 system/Entity/Entity.php                      |  4 +-
 system/Entity/Exceptions/CastException.php    | 27 ++-----
 system/Exceptions/CastException.php           | 27 ++-----
 system/Exceptions/FrameworkException.php      |  2 +-
 system/Files/File.php                         | 17 ++---
 system/Files/FileCollection.php               |  4 +-
 system/Filters/Filters.php                    |  4 +-
 system/HTTP/CURLRequest.php                   | 10 +--
 system/HTTP/ContentSecurityPolicy.php         |  2 +-
 system/HTTP/Files/FileCollection.php          |  6 +-
 system/HTTP/Files/UploadedFile.php            |  2 +-
 system/HTTP/Header.php                        |  4 +-
 system/HTTP/IncomingRequest.php               | 75 ++++++-------------
 system/HTTP/RedirectResponse.php              |  2 +-
 system/HTTP/RequestTrait.php                  |  4 +-
 system/HTTP/ResponseTrait.php                 | 15 ++--
 system/HTTP/SiteURI.php                       |  3 +-
 system/HTTP/SiteURIFactory.php                | 23 ++----
 system/HTTP/URI.php                           | 23 +++---
 system/HTTP/UserAgent.php                     |  3 +-
 system/Helpers/filesystem_helper.php          | 10 +--
 system/Helpers/form_helper.php                |  6 +-
 system/Helpers/html_helper.php                |  2 +-
 system/Helpers/number_helper.php              |  4 +-
 system/Helpers/text_helper.php                |  2 +-
 system/Honeypot/Honeypot.php                  |  2 +-
 system/Images/Handlers/BaseHandler.php        | 35 +++------
 system/Images/Handlers/ImageMagickHandler.php | 35 +++------
 system/Language/Language.php                  |  2 +-
 system/Log/Handlers/ChromeLoggerHandler.php   |  2 +-
 system/Log/Handlers/FileHandler.php           |  2 +-
 system/Log/Logger.php                         |  4 +-
 system/Model.php                              |  2 +-
 system/Pager/Pager.php                        |  2 +-
 system/Publisher/Publisher.php                |  4 +-
 system/RESTful/BaseResource.php               |  2 +-
 system/Router/AutoRouter.php                  |  6 +-
 system/Router/AutoRouterImproved.php          | 10 +--
 system/Router/RouteCollection.php             | 14 ++--
 system/Router/Router.php                      | 10 +--
 system/Security/Security.php                  |  2 +-
 system/Test/CIUnitTestCase.php                |  4 +-
 system/Test/ControllerTestTrait.php           |  2 +-
 system/Test/DOMParser.php                     |  6 +-
 system/Test/DatabaseTestTrait.php             |  2 +-
 system/Test/Fabricator.php                    | 19 ++---
 system/Test/FilterTestTrait.php               |  4 +-
 system/Test/TestLogger.php                    |  2 +-
 system/Typography/Typography.php              |  8 +-
 system/Validation/CreditCardRules.php         |  2 +-
 system/Validation/FormatRules.php             | 19 ++---
 system/Validation/Rules.php                   | 10 +--
 system/Validation/Validation.php              | 12 +--
 system/View/Cell.php                          |  8 +-
 system/View/Cells/Cell.php                    |  3 +-
 system/View/Filters.php                       | 19 ++---
 system/View/Parser.php                        | 10 +--
 tests/system/AutoReview/ComposerJsonTest.php  | 17 ++---
 tests/system/AutoReview/FrameworkCodeTest.php |  4 +-
 .../system/Commands/CommandGeneratorTest.php  |  2 +-
 tests/system/CommonFunctionsTest.php          |  4 +-
 tests/system/CommonHelperTest.php             |  4 +-
 tests/system/CommonSingleServiceTest.php      |  6 +-
 tests/system/ControllerTest.php               |  2 +-
 tests/system/Database/Live/DeleteTest.php     |  2 +-
 tests/system/Database/Live/GetTest.php        |  2 +-
 .../Database/Live/PreparedQueryTest.php       |  2 +-
 tests/system/Database/Live/UpdateTest.php     |  4 +-
 tests/system/Debug/ExceptionsTest.php         |  2 +-
 .../system/HTTP/ContentSecurityPolicyTest.php |  4 +-
 tests/system/Models/DeleteModelTest.php       |  2 +-
 119 files changed, 422 insertions(+), 633 deletions(-)

diff --git a/app/Views/errors/cli/error_exception.php b/app/Views/errors/cli/error_exception.php
index 98d83b0ed3a6..49bcd89131fb 100644
--- a/app/Views/errors/cli/error_exception.php
+++ b/app/Views/errors/cli/error_exception.php
@@ -3,7 +3,7 @@
 use CodeIgniter\CLI\CLI;
 
 // The main Exception
-CLI::write('[' . get_class($exception) . ']', 'light_gray', 'red');
+CLI::write('[' . $exception::class . ']', 'light_gray', 'red');
 CLI::write($message);
 CLI::write('at ' . CLI::color(clean_path($exception->getFile()) . ':' . $exception->getLine(), 'green'));
 CLI::newLine();
@@ -50,20 +50,11 @@
             $function .= $padClass . $error['function'];
         }
 
-        $args = implode(', ', array_map(static function ($value) {
-            switch (true) {
-                case is_object($value):
-                    return 'Object(' . get_class($value) . ')';
-
-                case is_array($value):
-                    return count($value) ? '[...]' : '[]';
-
-                case $value === null:
-                    return 'null'; // return the lowercased version
-
-                default:
-                    return var_export($value, true);
-            }
+        $args = implode(', ', array_map(static fn ($value) => match (true) {
+            is_object($value) => 'Object(' . $value::class . ')',
+            is_array($value)  => count($value) ? '[...]' : '[]',
+            $value === null   => 'null',
+            default           => var_export($value, true),
         }, array_values($error['args'] ?? [])));
 
         $function .= '(' . $args . ')';
diff --git a/app/Views/errors/html/error_exception.php b/app/Views/errors/html/error_exception.php
index 29a08d19caa8..98b48b9b6834 100644
--- a/app/Views/errors/html/error_exception.php
+++ b/app/Views/errors/html/error_exception.php
@@ -115,7 +115,7 @@
                                         <?php
                                         $params = null;
                                         // Reflection by name is not available for closure function
-                                        if (substr($row['function'], -1) !== '}') {
+                                        if (!str_ends_with($row['function'], '}')) {
                                             $mirror = isset($row['class']) ? new ReflectionMethod($row['class'], $row['function']) : new ReflectionFunction($row['function']);
                                             $params = $mirror->getParameters();
                                         }
diff --git a/system/Autoloader/Autoloader.php b/system/Autoloader/Autoloader.php
index 020dd5b1a4f2..bae6e95c878a 100644
--- a/system/Autoloader/Autoloader.php
+++ b/system/Autoloader/Autoloader.php
@@ -273,7 +273,7 @@ public function loadClass(string $class): void
      */
     protected function loadInNamespace(string $class)
     {
-        if (strpos($class, '\\') === false) {
+        if (! str_contains($class, '\\')) {
             return false;
         }
 
@@ -281,7 +281,7 @@ protected function loadInNamespace(string $class)
             foreach ($directories as $directory) {
                 $directory = rtrim($directory, '\\/');
 
-                if (strpos($class, $namespace) === 0) {
+                if (str_starts_with($class, $namespace)) {
                     $filePath = $directory . str_replace('\\', DIRECTORY_SEPARATOR, substr($class, strlen($namespace))) . '.php';
                     $filename = $this->includeFile($filePath);
 
@@ -415,7 +415,7 @@ private function loadComposerNamespaces(ClassLoader $composer, array $composerPa
 
             foreach ($srcPaths as $path) {
                 foreach ($installPaths as $installPath) {
-                    if ($installPath === substr($path, 0, strlen($installPath))) {
+                    if (str_starts_with($path, $installPath)) {
                         $add = true;
                         break 2;
                     }
diff --git a/system/Autoloader/FileLocator.php b/system/Autoloader/FileLocator.php
index e3821c1df27e..2484eda0860f 100644
--- a/system/Autoloader/FileLocator.php
+++ b/system/Autoloader/FileLocator.php
@@ -51,12 +51,12 @@ public function locateFile(string $file, ?string $folder = null, string $ext = '
         $file = $this->ensureExt($file, $ext);
 
         // Clears the folder name if it is at the beginning of the filename
-        if (! empty($folder) && strpos($file, $folder) === 0) {
+        if (! empty($folder) && str_starts_with($file, $folder)) {
             $file = substr($file, strlen($folder . '/'));
         }
 
         // Is not namespaced? Try the application folder.
-        if (strpos($file, '\\') === false) {
+        if (! str_contains($file, '\\')) {
             return $this->legacyLocate($file, $folder);
         }
 
@@ -101,7 +101,7 @@ public function locateFile(string $file, ?string $folder = null, string $ext = '
             // If we have a folder name, then the calling function
             // expects this file to be within that folder, like 'Views',
             // or 'libraries'.
-            if (! empty($folder) && strpos($path . $filename, '/' . $folder . '/') === false) {
+            if (! empty($folder) && ! str_contains($path . $filename, '/' . $folder . '/')) {
                 $path .= trim($folder, '/') . '/';
             }
 
@@ -188,7 +188,7 @@ public function search(string $path, string $ext = 'php', bool $prioritizeApp =
 
                 if ($prioritizeApp) {
                     $foundPaths[] = $fullPath;
-                } elseif (strpos($fullPath, APPPATH) === 0) {
+                } elseif (str_starts_with($fullPath, APPPATH)) {
                     $appPaths[] = $fullPath;
                 } else {
                     $foundPaths[] = $fullPath;
@@ -212,7 +212,7 @@ protected function ensureExt(string $path, string $ext): string
         if ($ext !== '') {
             $ext = '.' . $ext;
 
-            if (substr($path, -strlen($ext)) !== $ext) {
+            if (! str_ends_with($path, $ext)) {
                 $path .= $ext;
             }
         }
diff --git a/system/BaseModel.php b/system/BaseModel.php
index 7afdf9c1cb4d..14b2680875f7 100644
--- a/system/BaseModel.php
+++ b/system/BaseModel.php
@@ -577,7 +577,7 @@ public function find($id = null)
      */
     public function findColumn(string $columnName)
     {
-        if (strpos($columnName, ',') !== false) {
+        if (str_contains($columnName, ',')) {
             throw DataException::forFindColumnHaveMultipleColumns();
         }
 
@@ -1313,19 +1313,12 @@ protected function setDate(?int $userData = null)
      */
     protected function intToDate(int $value)
     {
-        switch ($this->dateFormat) {
-            case 'int':
-                return $value;
-
-            case 'datetime':
-                return date('Y-m-d H:i:s', $value);
-
-            case 'date':
-                return date('Y-m-d', $value);
-
-            default:
-                throw ModelException::forNoDateFormat(static::class);
-        }
+        return match ($this->dateFormat) {
+            'int'      => $value,
+            'datetime' => date('Y-m-d H:i:s', $value),
+            'date'     => date('Y-m-d', $value),
+            default    => throw ModelException::forNoDateFormat(static::class),
+        };
     }
 
     /**
@@ -1342,19 +1335,12 @@ protected function intToDate(int $value)
      */
     protected function timeToDate(Time $value)
     {
-        switch ($this->dateFormat) {
-            case 'datetime':
-                return $value->format('Y-m-d H:i:s');
-
-            case 'date':
-                return $value->format('Y-m-d');
-
-            case 'int':
-                return $value->getTimestamp();
-
-            default:
-                return (string) $value;
-        }
+        return match ($this->dateFormat) {
+            'datetime' => $value->format('Y-m-d H:i:s'),
+            'date'     => $value->format('Y-m-d'),
+            'int'      => $value->getTimestamp(),
+            default    => (string) $value,
+        };
     }
 
     /**
diff --git a/system/CLI/CLI.php b/system/CLI/CLI.php
index e2aa363e5851..23d5f05a2b4c 100644
--- a/system/CLI/CLI.php
+++ b/system/CLI/CLI.php
@@ -590,7 +590,7 @@ public static function color(string $text, string $foreground, ?string $backgrou
         $newText = '';
 
         // Detect if color method was already in use with this text
-        if (strpos($text, "\033[0m") !== false) {
+        if (str_contains($text, "\033[0m")) {
             $pattern = '/\\033\\[0;.+?\\033\\[0m/u';
 
             preg_match_all($pattern, $text, $matches);
diff --git a/system/CLI/Commands.php b/system/CLI/Commands.php
index 7cb5351cf3b5..0c9bcabae37d 100644
--- a/system/CLI/Commands.php
+++ b/system/CLI/Commands.php
@@ -174,7 +174,7 @@ protected function getCommandAlternatives(string $name, array $collection): arra
         foreach (array_keys($collection) as $commandName) {
             $lev = levenshtein($name, $commandName);
 
-            if ($lev <= strlen($commandName) / 3 || strpos($commandName, $name) !== false) {
+            if ($lev <= strlen($commandName) / 3 || str_contains($commandName, $name)) {
                 $alternatives[$commandName] = $lev;
             }
         }
diff --git a/system/CLI/GeneratorTrait.php b/system/CLI/GeneratorTrait.php
index c1112ca63481..c2260b4abb71 100644
--- a/system/CLI/GeneratorTrait.php
+++ b/system/CLI/GeneratorTrait.php
@@ -309,7 +309,7 @@ protected function qualifyClassName(): string
             '\\'
         ) . '\\';
 
-        if (strncmp($class, $namespace, strlen($namespace)) === 0) {
+        if (str_starts_with($class, $namespace)) {
             return $class; // @codeCoverageIgnore
         }
 
diff --git a/system/Cache/Handlers/PredisHandler.php b/system/Cache/Handlers/PredisHandler.php
index 986d083ebc69..d9b3701517ad 100644
--- a/system/Cache/Handlers/PredisHandler.php
+++ b/system/Cache/Handlers/PredisHandler.php
@@ -86,22 +86,11 @@ public function get(string $key)
             return null;
         }
 
-        switch ($data['__ci_type']) {
-            case 'array':
-            case 'object':
-                return unserialize($data['__ci_value']);
-
-            case 'boolean':
-            case 'integer':
-            case 'double': // Yes, 'double' is returned and NOT 'float'
-            case 'string':
-            case 'NULL':
-                return settype($data['__ci_value'], $data['__ci_type']) ? $data['__ci_value'] : null;
-
-            case 'resource':
-            default:
-                return null;
-        }
+        return match ($data['__ci_type']) {
+            'array', 'object' => unserialize($data['__ci_value']),
+            'boolean', 'integer', 'double', 'string', 'NULL' => settype($data['__ci_value'], $data['__ci_type']) ? $data['__ci_value'] : null,
+            default => null,
+        };
     }
 
     /**
diff --git a/system/Cache/Handlers/RedisHandler.php b/system/Cache/Handlers/RedisHandler.php
index 953de2dc20be..bbba78eb1b9b 100644
--- a/system/Cache/Handlers/RedisHandler.php
+++ b/system/Cache/Handlers/RedisHandler.php
@@ -112,22 +112,11 @@ public function get(string $key)
             return null;
         }
 
-        switch ($data['__ci_type']) {
-            case 'array':
-            case 'object':
-                return unserialize($data['__ci_value']);
-
-            case 'boolean':
-            case 'integer':
-            case 'double': // Yes, 'double' is returned and NOT 'float'
-            case 'string':
-            case 'NULL':
-                return settype($data['__ci_value'], $data['__ci_type']) ? $data['__ci_value'] : null;
-
-            case 'resource':
-            default:
-                return null;
-        }
+        return match ($data['__ci_type']) {
+            'array', 'object' => unserialize($data['__ci_value']),
+            'boolean', 'integer', 'double', 'string', 'NULL' => settype($data['__ci_value'], $data['__ci_type']) ? $data['__ci_value'] : null,
+            default => null,
+        };
     }
 
     /**
diff --git a/system/CodeIgniter.php b/system/CodeIgniter.php
index 87a2a55b0caa..c508e8afdcde 100644
--- a/system/CodeIgniter.php
+++ b/system/CodeIgniter.php
@@ -867,7 +867,7 @@ protected function startController()
         $this->benchmark->start('controller_constructor');
 
         // Is it routed to a Closure?
-        if (is_object($this->controller) && (get_class($this->controller) === 'Closure')) {
+        if (is_object($this->controller) && ($this->controller::class === 'Closure')) {
             $controller = $this->controller;
 
             return $controller(...$this->router->params());
@@ -1038,7 +1038,7 @@ public function storePreviousURL($uri)
         }
 
         // Ignore non-HTML responses
-        if (strpos($this->response->getHeaderLine('Content-Type'), 'text/html') === false) {
+        if (! str_contains($this->response->getHeaderLine('Content-Type'), 'text/html')) {
             return;
         }
 
diff --git a/system/Commands/Database/CreateDatabase.php b/system/Commands/Database/CreateDatabase.php
index d103d97f689a..32643320b00f 100644
--- a/system/Commands/Database/CreateDatabase.php
+++ b/system/Commands/Database/CreateDatabase.php
@@ -107,7 +107,7 @@ public function run(array $params)
                 $config->{$group}['database'] = $name;
 
                 if ($name !== ':memory:') {
-                    $dbName = strpos($name, DIRECTORY_SEPARATOR) === false ? WRITEPATH . $name : $name;
+                    $dbName = ! str_contains($name, DIRECTORY_SEPARATOR) ? WRITEPATH . $name : $name;
 
                     if (is_file($dbName)) {
                         CLI::error("Database \"{$dbName}\" already exists.", 'light_gray', 'red');
diff --git a/system/Commands/Encryption/GenerateKey.php b/system/Commands/Encryption/GenerateKey.php
index 419ae6ef3e34..c10a76e81e43 100644
--- a/system/Commands/Encryption/GenerateKey.php
+++ b/system/Commands/Encryption/GenerateKey.php
@@ -166,7 +166,7 @@ protected function writeNewEncryptionKeyToFile(string $oldKey, string $newKey):
         $oldFileContents = (string) file_get_contents($envFile);
         $replacementKey  = "\nencryption.key = {$newKey}";
 
-        if (strpos($oldFileContents, 'encryption.key') === false) {
+        if (! str_contains($oldFileContents, 'encryption.key')) {
             return file_put_contents($envFile, $replacementKey, FILE_APPEND) !== false;
         }
 
diff --git a/system/Commands/Utilities/Publish.php b/system/Commands/Utilities/Publish.php
index 1e4103c114d8..f1abd7433113 100644
--- a/system/Commands/Utilities/Publish.php
+++ b/system/Commands/Utilities/Publish.php
@@ -83,13 +83,13 @@ public function run(array $params)
         foreach ($publishers as $publisher) {
             if ($publisher->publish()) {
                 CLI::write(lang('Publisher.publishSuccess', [
-                    get_class($publisher),
+                    $publisher::class,
                     count($publisher->getPublished()),
                     $publisher->getDestination(),
                 ]), 'green');
             } else {
                 CLI::error(lang('Publisher.publishFailure', [
-                    get_class($publisher),
+                    $publisher::class,
                     $publisher->getDestination(),
                 ]), 'light_gray', 'red');
 
diff --git a/system/Commands/Utilities/Routes/AutoRouterImproved/ControllerMethodReader.php b/system/Commands/Utilities/Routes/AutoRouterImproved/ControllerMethodReader.php
index 73da88630d5d..460a4a89ccef 100644
--- a/system/Commands/Utilities/Routes/AutoRouterImproved/ControllerMethodReader.php
+++ b/system/Commands/Utilities/Routes/AutoRouterImproved/ControllerMethodReader.php
@@ -65,7 +65,7 @@ public function read(string $class, string $defaultController = 'Home', string $
             $methodName = $method->getName();
 
             foreach ($this->httpMethods as $httpVerb) {
-                if (strpos($methodName, strtolower($httpVerb)) === 0) {
+                if (str_starts_with($methodName, strtolower($httpVerb))) {
                     // Remove HTTP verb prefix.
                     $methodInUri = lcfirst(substr($methodName, strlen($httpVerb)));
 
diff --git a/system/Commands/Utilities/Routes/FilterFinder.php b/system/Commands/Utilities/Routes/FilterFinder.php
index cc1f6d2b05f4..8788a164ac88 100644
--- a/system/Commands/Utilities/Routes/FilterFinder.php
+++ b/system/Commands/Utilities/Routes/FilterFinder.php
@@ -65,12 +65,12 @@ public function find(string $uri): array
             $this->filters->initialize($uri);
 
             return $this->filters->getFilters();
-        } catch (RedirectException $e) {
+        } catch (RedirectException) {
             return [
                 'before' => [],
                 'after'  => [],
             ];
-        } catch (PageNotFoundException $e) {
+        } catch (PageNotFoundException) {
             return [
                 'before' => ['<unknown>'],
                 'after'  => ['<unknown>'],
diff --git a/system/Common.php b/system/Common.php
index 0f8aa3e7ad27..66115c819164 100644
--- a/system/Common.php
+++ b/system/Common.php
@@ -92,29 +92,18 @@ function clean_path(string $path): string
         // Resolve relative paths
         try {
             $path = realpath($path) ?: $path;
-        } catch (ErrorException|ValueError $e) {
+        } catch (ErrorException|ValueError) {
             $path = 'error file path: ' . urlencode($path);
         }
 
-        switch (true) {
-            case strpos($path, APPPATH) === 0:
-                return 'APPPATH' . DIRECTORY_SEPARATOR . substr($path, strlen(APPPATH));
-
-            case strpos($path, SYSTEMPATH) === 0:
-                return 'SYSTEMPATH' . DIRECTORY_SEPARATOR . substr($path, strlen(SYSTEMPATH));
-
-            case strpos($path, FCPATH) === 0:
-                return 'FCPATH' . DIRECTORY_SEPARATOR . substr($path, strlen(FCPATH));
-
-            case defined('VENDORPATH') && strpos($path, VENDORPATH) === 0:
-                return 'VENDORPATH' . DIRECTORY_SEPARATOR . substr($path, strlen(VENDORPATH));
-
-            case strpos($path, ROOTPATH) === 0:
-                return 'ROOTPATH' . DIRECTORY_SEPARATOR . substr($path, strlen(ROOTPATH));
-
-            default:
-                return $path;
-        }
+        return match (true) {
+            str_starts_with($path, APPPATH)                             => 'APPPATH' . DIRECTORY_SEPARATOR . substr($path, strlen(APPPATH)),
+            str_starts_with($path, SYSTEMPATH)                          => 'SYSTEMPATH' . DIRECTORY_SEPARATOR . substr($path, strlen(SYSTEMPATH)),
+            str_starts_with($path, FCPATH)                              => 'FCPATH' . DIRECTORY_SEPARATOR . substr($path, strlen(FCPATH)),
+            defined('VENDORPATH') && str_starts_with($path, VENDORPATH) => 'VENDORPATH' . DIRECTORY_SEPARATOR . substr($path, strlen(VENDORPATH)),
+            str_starts_with($path, ROOTPATH)                            => 'ROOTPATH' . DIRECTORY_SEPARATOR . substr($path, strlen(ROOTPATH)),
+            default                                                     => $path,
+        };
     }
 }
 
@@ -382,22 +371,13 @@ function env(string $key, $default = null)
             return $default;
         }
 
-        // Handle any boolean values
-        switch (strtolower($value)) {
-            case 'true':
-                return true;
-
-            case 'false':
-                return false;
-
-            case 'empty':
-                return '';
-
-            case 'null':
-                return null;
-        }
-
-        return $value;
+        return match (strtolower($value)) {
+            'true'  => true,
+            'false' => false,
+            'empty' => '',
+            'null'  => null,
+            default => $value,
+        };
     }
 }
 
@@ -592,7 +572,7 @@ function helper($filenames): void
             $appHelper     = null;
             $localIncludes = [];
 
-            if (strpos($filename, '_helper') === false) {
+            if (! str_contains($filename, '_helper')) {
                 $filename .= '_helper';
             }
 
@@ -603,7 +583,7 @@ function helper($filenames): void
 
             // If the file is namespaced, we'll just grab that
             // file and not search for any others
-            if (strpos($filename, '\\') !== false) {
+            if (str_contains($filename, '\\')) {
                 $path = $loader->locateFile($filename, 'Helpers');
 
                 if (empty($path)) {
@@ -617,9 +597,9 @@ function helper($filenames): void
                 $paths = $loader->search('Helpers/' . $filename);
 
                 foreach ($paths as $path) {
-                    if (strpos($path, APPPATH . 'Helpers' . DIRECTORY_SEPARATOR) === 0) {
+                    if (str_starts_with($path, APPPATH . 'Helpers' . DIRECTORY_SEPARATOR)) {
                         $appHelper = $path;
-                    } elseif (strpos($path, SYSTEMPATH . 'Helpers' . DIRECTORY_SEPARATOR) === 0) {
+                    } elseif (str_starts_with($path, SYSTEMPATH . 'Helpers' . DIRECTORY_SEPARATOR)) {
                         $systemHelper = $path;
                     } else {
                         $localIncludes[] = $path;
@@ -1209,7 +1189,7 @@ function view_cell(string $library, $params = null, int $ttl = 0, ?string $cache
      */
     function class_basename($class)
     {
-        $class = is_object($class) ? get_class($class) : $class;
+        $class = is_object($class) ? $class::class : $class;
 
         return basename(str_replace('\\', '/', $class));
     }
@@ -1228,7 +1208,7 @@ function class_basename($class)
     function class_uses_recursive($class)
     {
         if (is_object($class)) {
-            $class = get_class($class);
+            $class = $class::class;
         }
 
         $results = [];
diff --git a/system/ComposerScripts.php b/system/ComposerScripts.php
index 021079da468d..a3cda28fe063 100644
--- a/system/ComposerScripts.php
+++ b/system/ComposerScripts.php
@@ -71,7 +71,7 @@ public static function postUpdate()
 
         foreach (self::$dependencies as $key => $dependency) {
             // Kint may be removed.
-            if (! is_dir($dependency['from']) && strpos($key, 'kint') === 0) {
+            if (! is_dir($dependency['from']) && str_starts_with($key, 'kint')) {
                 continue;
             }
 
diff --git a/system/Config/BaseConfig.php b/system/Config/BaseConfig.php
index 216ce81fd5e9..a796438ca0cb 100644
--- a/system/Config/BaseConfig.php
+++ b/system/Config/BaseConfig.php
@@ -120,10 +120,10 @@ public function __construct()
             $this->initEnvValue($this->{$property}, $property, $prefix, $shortPrefix);
 
             if ($this instanceof Encryption && $property === 'key') {
-                if (strpos($this->{$property}, 'hex2bin:') === 0) {
+                if (str_starts_with($this->{$property}, 'hex2bin:')) {
                     // Handle hex2bin prefix
                     $this->{$property} = hex2bin(substr($this->{$property}, 8));
-                } elseif (strpos($this->{$property}, 'base64:') === 0) {
+                } elseif (str_starts_with($this->{$property}, 'base64:')) {
                     // Handle base64 prefix
                     $this->{$property} = base64_decode(substr($this->{$property}, 7), true);
                 }
diff --git a/system/Config/DotEnv.php b/system/Config/DotEnv.php
index 05ecab900c3e..01c51ebf2f9e 100644
--- a/system/Config/DotEnv.php
+++ b/system/Config/DotEnv.php
@@ -68,12 +68,12 @@ public function parse(): ?array
 
         foreach ($lines as $line) {
             // Is it a comment?
-            if (strpos(trim($line), '#') === 0) {
+            if (str_starts_with(trim($line), '#')) {
                 continue;
             }
 
             // If there is an equal sign, then we know we are assigning a variable.
-            if (strpos($line, '=') !== false) {
+            if (str_contains($line, '=')) {
                 [$name, $value] = $this->normaliseVariable($line);
                 $vars[$name]    = $value;
                 $this->setVariable($name, $value);
@@ -112,7 +112,7 @@ protected function setVariable(string $name, string $value = '')
     public function normaliseVariable(string $name, string $value = ''): array
     {
         // Split our compound string into its parts.
-        if (strpos($name, '=') !== false) {
+        if (str_contains($name, '=')) {
             [$name, $value] = explode('=', $name, 2);
         }
 
@@ -192,7 +192,7 @@ protected function sanitizeValue(string $value): string
      */
     protected function resolveNestedVariables(string $value): string
     {
-        if (strpos($value, '$') !== false) {
+        if (str_contains($value, '$')) {
             $value = preg_replace_callback(
                 '/\${([a-zA-Z0-9_\.]+)}/',
                 function ($matchedPatterns) {
diff --git a/system/Config/Factories.php b/system/Config/Factories.php
index 253cd3f7a7c9..f2a59522af73 100644
--- a/system/Config/Factories.php
+++ b/system/Config/Factories.php
@@ -316,7 +316,7 @@ class_exists($alias, false)
      */
     private static function isNamespaced(string $alias): bool
     {
-        return strpos($alias, '\\') !== false;
+        return str_contains($alias, '\\');
     }
 
     /**
@@ -334,10 +334,10 @@ private static function verifyPreferApp(array $options, string $alias): bool
 
         // Special case for Config since its App namespace is actually \Config
         if (self::isConfig($options['component'])) {
-            return strpos($alias, 'Config') === 0;
+            return str_starts_with($alias, 'Config');
         }
 
-        return strpos($alias, APP_NAMESPACE) === 0;
+        return str_starts_with($alias, APP_NAMESPACE);
     }
 
     /**
@@ -461,7 +461,7 @@ public static function injectMock(string $component, string $alias, object $inst
         // Force a configuration to exist for this component
         self::getOptions($component);
 
-        $class = get_class($instance);
+        $class = $instance::class;
 
         self::$instances[$component][$class] = $instance;
         self::$aliases[$component][$alias]   = $class;
diff --git a/system/Cookie/Cookie.php b/system/Cookie/Cookie.php
index 68a748cb30eb..96248099a02e 100644
--- a/system/Cookie/Cookie.php
+++ b/system/Cookie/Cookie.php
@@ -19,6 +19,7 @@
 use InvalidArgumentException;
 use LogicException;
 use ReturnTypeWillChange;
+use Stringable;
 
 /**
  * A `Cookie` class represents an immutable HTTP cookie value object.
@@ -41,7 +42,7 @@
  * @template-implements ArrayAccess<string, bool|int|string>
  * @see \CodeIgniter\Cookie\CookieTest
  */
-class Cookie implements ArrayAccess, CloneableCookieInterface
+class Cookie implements ArrayAccess, CloneableCookieInterface, Stringable
 {
     /**
      * @var string
@@ -159,7 +160,6 @@ public static function setDefaults($config = [])
     // =========================================================================
     // CONSTRUCTORS
     // =========================================================================
-
     /**
      * Create a new Cookie instance from a `Set-Cookie` header.
      *
@@ -180,7 +180,7 @@ public static function fromHeaderString(string $cookie, bool $raw = false)
         unset($part);
 
         foreach ($parts as $part) {
-            if (strpos($part, '=') !== false) {
+            if (str_contains($part, '=')) {
                 [$attr, $val] = explode('=', $part);
             } else {
                 $attr = $part;
@@ -245,7 +245,6 @@ final public function __construct(string $name, string $value = '', array $optio
     // =========================================================================
     // GETTERS
     // =========================================================================
-
     /**
      * {@inheritDoc}
      */
@@ -398,7 +397,6 @@ public function getOptions(): array
     // =========================================================================
     // CLONING
     // =========================================================================
-
     /**
      * {@inheritDoc}
      */
@@ -563,7 +561,6 @@ public function withRaw(bool $raw = true)
     // =========================================================================
     // ARRAY ACCESS FOR BC
     // =========================================================================
-
     /**
      * Whether an offset exists.
      *
@@ -621,7 +618,6 @@ public function offsetUnset($offset): void
     // =========================================================================
     // CONVERTERS
     // =========================================================================
-
     /**
      * {@inheritDoc}
      */
@@ -723,7 +719,6 @@ protected static function convertExpiresTimestamp($expires = 0): int
     // =========================================================================
     // VALIDATION
     // =========================================================================
-
     /**
      * Validates the cookie name per RFC 2616.
      *
@@ -750,11 +745,11 @@ protected function validateName(string $name, bool $raw): void
      */
     protected function validatePrefix(string $prefix, bool $secure, string $path, string $domain): void
     {
-        if (strpos($prefix, '__Secure-') === 0 && ! $secure) {
+        if (str_starts_with($prefix, '__Secure-') && ! $secure) {
             throw CookieException::forInvalidSecurePrefix();
         }
 
-        if (strpos($prefix, '__Host-') === 0 && (! $secure || $domain !== '' || $path !== '/')) {
+        if (str_starts_with($prefix, '__Host-') && (! $secure || $domain !== '' || $path !== '/')) {
             throw CookieException::forInvalidHostPrefix();
         }
     }
diff --git a/system/Cookie/CookieStore.php b/system/Cookie/CookieStore.php
index d893a4add116..867ffcecf976 100644
--- a/system/Cookie/CookieStore.php
+++ b/system/Cookie/CookieStore.php
@@ -223,7 +223,7 @@ public function getIterator(): Traversable
     protected function validateCookies(array $cookies): void
     {
         foreach ($cookies as $index => $cookie) {
-            $type = is_object($cookie) ? get_class($cookie) : gettype($cookie);
+            $type = get_debug_type($cookie);
 
             if (! $cookie instanceof Cookie) {
                 throw CookieException::forInvalidCookieInstance([static::class, Cookie::class, $type, $index]);
diff --git a/system/Database/BaseBuilder.php b/system/Database/BaseBuilder.php
index badf2d35cdfc..5c86942be008 100644
--- a/system/Database/BaseBuilder.php
+++ b/system/Database/BaseBuilder.php
@@ -310,7 +310,7 @@ public function __construct($tableName, ConnectionInterface $db, ?array $options
         $this->db = $db;
 
         // If it contains `,`, it has multiple tables
-        if (is_string($tableName) && strpos($tableName, ',') === false) {
+        if (is_string($tableName) && ! str_contains($tableName, ',')) {
             $this->tableName = $tableName;  // @TODO remove alias if exists
         } else {
             $this->tableName = '';
@@ -508,7 +508,7 @@ protected function maxMinAvgSum(string $select = '', string $alias = '', string
             throw DataException::forEmptyInputGiven('Select');
         }
 
-        if (strpos($select, ',') !== false) {
+        if (str_contains($select, ',')) {
             throw DataException::forInvalidArgument('column name not separated by comma');
         }
 
@@ -535,7 +535,7 @@ protected function maxMinAvgSum(string $select = '', string $alias = '', string
      */
     protected function createAliasFromTable(string $item): string
     {
-        if (strpos($item, '.') !== false) {
+        if (str_contains($item, '.')) {
             $item = explode('.', $item);
 
             return end($item);
@@ -571,7 +571,7 @@ public function from($from, bool $overwrite = false): self
         }
 
         foreach ((array) $from as $table) {
-            if (strpos($table, ',') !== false) {
+            if (str_contains($table, ',')) {
                 $this->from(explode(',', $table));
             } else {
                 $table = trim($table);
@@ -760,7 +760,7 @@ protected function whereHaving(string $qbKey, $key, $value = null, string $type
                     $op = trim(current($op));
 
                     // Does the key end with operator?
-                    if (substr($k, -strlen($op)) === $op) {
+                    if (str_ends_with($k, $op)) {
                         $k  = rtrim(substr($k, 0, -strlen($op)));
                         $op = " {$op}";
                     } else {
@@ -2318,7 +2318,7 @@ public function insert($set = null, ?bool $escape = null)
      */
     protected function removeAlias(string $from): string
     {
-        if (strpos($from, ' ') !== false) {
+        if (str_contains($from, ' ')) {
             // if the alias is written with the AS keyword, remove it
             $from = preg_replace('/\s+AS\s+/i', ' ', $from);
 
@@ -2966,12 +2966,12 @@ protected function trackAliases($table)
 
         // Does the string contain a comma?  If so, we need to separate
         // the string into discreet statements
-        if (strpos($table, ',') !== false) {
+        if (str_contains($table, ',')) {
             return $this->trackAliases(explode(',', $table));
         }
 
         // if a table alias is used we can recognize it by a space
-        if (strpos($table, ' ') !== false) {
+        if (str_contains($table, ' ')) {
             // if the alias is written with the AS keyword, remove it
             $table = preg_replace('/\s+AS\s+/i', ' ', $table);
 
@@ -3111,11 +3111,11 @@ protected function compileWhereHaving(string $qbKey): string
 
                     if (! empty($matches[4])) {
                         $protectIdentifiers = false;
-                        if (strpos($matches[4], '.') !== false) {
+                        if (str_contains($matches[4], '.')) {
                             $protectIdentifiers = true;
                         }
 
-                        if (strpos($matches[4], ':') === false) {
+                        if (! str_contains($matches[4], ':')) {
                             $matches[4] = $this->db->protectIdentifiers(trim($matches[4]), false, $protectIdentifiers);
                         }
 
diff --git a/system/Database/BaseConnection.php b/system/Database/BaseConnection.php
index 6d92965f0b94..fd2c278a084f 100644
--- a/system/Database/BaseConnection.php
+++ b/system/Database/BaseConnection.php
@@ -1067,7 +1067,7 @@ public function protectIdentifiers($item, bool $prefixSingle = false, ?bool $pro
         // Break the string apart if it contains periods, then insert the table prefix
         // in the correct location, assuming the period doesn't indicate that we're dealing
         // with an alias. While we're at it, we will escape the components
-        if (strpos($item, '.') !== false) {
+        if (str_contains($item, '.')) {
             return $this->protectDotItem($item, $alias, $protectIdentifiers, $fieldExists);
         }
 
@@ -1079,11 +1079,11 @@ public function protectIdentifiers($item, bool $prefixSingle = false, ?bool $pro
         // Is there a table prefix? If not, no need to insert it
         if ($this->DBPrefix !== '') {
             // Verify table prefix and replace if necessary
-            if ($this->swapPre !== '' && strpos($item, $this->swapPre) === 0) {
+            if ($this->swapPre !== '' && str_starts_with($item, $this->swapPre)) {
                 $item = preg_replace('/^' . $this->swapPre . '(\S+?)/', $this->DBPrefix . '\\1', $item);
             }
             // Do we prefix an item with no segments?
-            elseif ($prefixSingle === true && strpos($item, $this->DBPrefix) !== 0) {
+            elseif ($prefixSingle === true && ! str_starts_with($item, $this->DBPrefix)) {
                 $item = $this->DBPrefix . $item;
             }
         }
@@ -1145,11 +1145,11 @@ private function protectDotItem(string $item, string $alias, bool $protectIdenti
             }
 
             // Verify table prefix and replace if necessary
-            if ($this->swapPre !== '' && strpos($parts[$i], $this->swapPre) === 0) {
+            if ($this->swapPre !== '' && str_starts_with($parts[$i], $this->swapPre)) {
                 $parts[$i] = preg_replace('/^' . $this->swapPre . '(\S+?)/', $this->DBPrefix . '\\1', $parts[$i]);
             }
             // We only add the table prefix if it does not already exist
-            elseif (strpos($parts[$i], $this->DBPrefix) !== 0) {
+            elseif (! str_starts_with($parts[$i], $this->DBPrefix)) {
                 $parts[$i] = $this->DBPrefix . $parts[$i];
             }
 
@@ -1192,7 +1192,7 @@ public function escapeIdentifiers($item)
         if (ctype_digit($item)
             || $item[0] === "'"
             || ($this->escapeChar !== '"' && $item[0] === '"')
-            || strpos($item, '(') !== false) {
+            || str_contains($item, '(')) {
             return $item;
         }
 
@@ -1212,7 +1212,7 @@ public function escapeIdentifiers($item)
 
         foreach ($this->reservedIdentifiers as $id) {
             /** @psalm-suppress NoValue I don't know why ERROR. */
-            if (strpos($item, '.' . $id) !== false) {
+            if (str_contains($item, '.' . $id)) {
                 return preg_replace(
                     '/' . $this->pregEscapeChar[0] . '?([^' . $this->pregEscapeChar[1] . '\.]+)' . $this->pregEscapeChar[1] . '?\./i',
                     $this->pregEscapeChar[2] . '$1' . $this->pregEscapeChar[3] . '.',
@@ -1358,7 +1358,7 @@ public function callFunction(string $functionName, ...$params): bool
     {
         $driver = $this->getDriverFunctionPrefix();
 
-        if (strpos($driver, $functionName) === false) {
+        if (! str_contains($driver, $functionName)) {
             $functionName = $driver . $functionName;
         }
 
diff --git a/system/Database/Database.php b/system/Database/Database.php
index 2818fe220928..7d8921663faf 100644
--- a/system/Database/Database.php
+++ b/system/Database/Database.php
@@ -44,7 +44,7 @@ public function load(array $params = [], string $alias = '')
             throw new InvalidArgumentException('You must supply the parameter: alias.');
         }
 
-        if (! empty($params['DSN']) && strpos($params['DSN'], '://') !== false) {
+        if (! empty($params['DSN']) && str_contains($params['DSN'], '://')) {
             $params = $this->parseDSN($params);
         }
 
@@ -130,7 +130,7 @@ protected function parseDSN(array $params): array
      */
     protected function initDriver(string $driver, string $class, $argument): object
     {
-        $classname = (strpos($driver, '\\') === false)
+        $classname = (! str_contains($driver, '\\'))
             ? "CodeIgniter\\Database\\{$driver}\\{$class}"
             : $driver . '\\' . $class;
 
diff --git a/system/Database/Forge.php b/system/Database/Forge.php
index 57e43bf199fe..cb0e21c64911 100644
--- a/system/Database/Forge.php
+++ b/system/Database/Forge.php
@@ -368,7 +368,7 @@ public function addField($field)
                 ]);
                 $this->addKey('id', true);
             } else {
-                if (strpos($field, ' ') === false) {
+                if (! str_contains($field, ' ')) {
                     throw new InvalidArgumentException('Field information is required for that operation.');
                 }
 
@@ -624,7 +624,7 @@ public function dropTable(string $tableName, bool $ifExists = false, bool $casca
             return false;
         }
 
-        if ($this->db->DBPrefix && strpos($tableName, $this->db->DBPrefix) === 0) {
+        if ($this->db->DBPrefix && str_starts_with($tableName, $this->db->DBPrefix)) {
             $tableName = substr($tableName, strlen($this->db->DBPrefix));
         }
 
diff --git a/system/Database/MigrationRunner.php b/system/Database/MigrationRunner.php
index 4b342eeaac39..0beac62fe701 100644
--- a/system/Database/MigrationRunner.php
+++ b/system/Database/MigrationRunner.php
@@ -447,7 +447,7 @@ public function findNamespaceMigrations(string $namespace): array
      */
     protected function migrationFromFile(string $path, string $namespace)
     {
-        if (substr($path, -4) !== '.php') {
+        if (! str_ends_with($path, '.php')) {
             return false;
         }
 
diff --git a/system/Database/OCI8/Connection.php b/system/Database/OCI8/Connection.php
index 8cb7e3a4a766..510655f38686 100644
--- a/system/Database/OCI8/Connection.php
+++ b/system/Database/OCI8/Connection.php
@@ -221,7 +221,7 @@ protected function execute(string $sql)
     public function parseInsertTableName(string $sql): string
     {
         $commentStrippedSql = preg_replace(['/\/\*(.|\n)*?\*\//m', '/--.+/'], '', $sql);
-        $isInsertQuery      = strpos(strtoupper(ltrim($commentStrippedSql)), 'INSERT') === 0;
+        $isInsertQuery      = str_starts_with(strtoupper(ltrim($commentStrippedSql)), 'INSERT');
 
         if (! $isInsertQuery) {
             return '';
@@ -230,7 +230,7 @@ public function parseInsertTableName(string $sql): string
         preg_match('/(?is)\b(?:into)\s+("?\w+"?)/', $commentStrippedSql, $match);
         $tableName = $match[1] ?? '';
 
-        return strpos($tableName, '"') === 0 ? trim($tableName, '"') : strtoupper($tableName);
+        return str_starts_with($tableName, '"') ? trim($tableName, '"') : strtoupper($tableName);
     }
 
     /**
@@ -267,7 +267,7 @@ protected function _listTables(bool $prefixLimit = false, ?string $tableName = n
      */
     protected function _listColumns(string $table = ''): string
     {
-        if (strpos($table, '.') !== false) {
+        if (str_contains($table, '.')) {
             sscanf($table, '%[^.].%s', $owner, $table);
         } else {
             $owner = $this->username;
@@ -287,7 +287,7 @@ protected function _listColumns(string $table = ''): string
      */
     protected function _fieldData(string $table): array
     {
-        if (strpos($table, '.') !== false) {
+        if (str_contains($table, '.')) {
             sscanf($table, '%[^.].%s', $owner, $table);
         } else {
             $owner = $this->username;
@@ -335,7 +335,7 @@ protected function _fieldData(string $table): array
      */
     protected function _indexData(string $table): array
     {
-        if (strpos($table, '.') !== false) {
+        if (str_contains($table, '.')) {
             sscanf($table, '%[^.].%s', $owner, $table);
         } else {
             $owner = $this->username;
@@ -633,7 +633,7 @@ protected function buildDSN()
             return;
         }
 
-        $isEasyConnectableHostName = $this->hostname !== '' && strpos($this->hostname, '/') === false && strpos($this->hostname, ':') === false;
+        $isEasyConnectableHostName = $this->hostname !== '' && ! str_contains($this->hostname, '/') && ! str_contains($this->hostname, ':');
         $easyConnectablePort       = ! empty($this->port) && ctype_digit($this->port) ? ':' . $this->port : '';
         $easyConnectableDatabase   = $this->database !== '' ? '/' . ltrim($this->database, '/') : '';
 
diff --git a/system/Database/OCI8/Forge.php b/system/Database/OCI8/Forge.php
index 6e1e85f666a1..be2dc2181f0c 100644
--- a/system/Database/OCI8/Forge.php
+++ b/system/Database/OCI8/Forge.php
@@ -122,7 +122,7 @@ protected function _alterTable(string $alterType, string $table, $field)
                 // so add null constraint is used only when it is different from the current null constraint.
                 // If a not null constraint is added to a column with a not null constraint,
                 // ORA-01442 will occur.
-                $wantToAddNull   = strpos($field[$i]['null'], ' NOT') === false;
+                $wantToAddNull   = ! str_contains($field[$i]['null'], ' NOT');
                 $currentNullable = $nullableMap[$field[$i]['name']];
 
                 if ($wantToAddNull === true && $currentNullable === true) {
@@ -188,7 +188,7 @@ protected function _processColumn(array $field): string
     {
         $constraint = '';
         // @todo: can't cover multi pattern when set type.
-        if ($field['type'] === 'VARCHAR2' && strpos($field['length'], "('") === 0) {
+        if ($field['type'] === 'VARCHAR2' && str_starts_with($field['length'], "('")) {
             $constraint = ' CHECK(' . $this->db->escapeIdentifiers($field['name'])
                 . ' IN ' . $field['length'] . ')';
 
diff --git a/system/Database/Postgre/Connection.php b/system/Database/Postgre/Connection.php
index 56905ec922d2..53fe40ea4ca0 100644
--- a/system/Database/Postgre/Connection.php
+++ b/system/Database/Postgre/Connection.php
@@ -353,10 +353,10 @@ protected function _indexData(string $table): array
             $_fields     = explode(',', preg_replace('/^.*\((.+?)\)$/', '$1', trim($row->indexdef)));
             $obj->fields = array_map(static fn ($v) => trim($v), $_fields);
 
-            if (strpos($row->indexdef, 'CREATE UNIQUE INDEX pk') === 0) {
+            if (str_starts_with($row->indexdef, 'CREATE UNIQUE INDEX pk')) {
                 $obj->type = 'PRIMARY';
             } else {
-                $obj->type = (strpos($row->indexdef, 'CREATE UNIQUE') === 0) ? 'UNIQUE' : 'INDEX';
+                $obj->type = (str_starts_with($row->indexdef, 'CREATE UNIQUE')) ? 'UNIQUE' : 'INDEX';
             }
 
             $retVal[$obj->name] = $obj;
@@ -493,7 +493,7 @@ protected function buildDSN()
         }
 
         // If UNIX sockets are used, we shouldn't set a port
-        if (strpos($this->hostname, '/') !== false) {
+        if (str_contains($this->hostname, '/')) {
             $this->port = '';
         }
 
diff --git a/system/Database/Query.php b/system/Database/Query.php
index 897a668f1376..898951e09bce 100644
--- a/system/Database/Query.php
+++ b/system/Database/Query.php
@@ -11,10 +11,12 @@
 
 namespace CodeIgniter\Database;
 
+use Stringable;
+
 /**
  * Query builder
  */
-class Query implements QueryInterface
+class Query implements QueryInterface, Stringable
 {
     /**
      * The query string, as provided by the user.
diff --git a/system/Database/RawSql.php b/system/Database/RawSql.php
index efa97d30736c..e45921d42e7a 100644
--- a/system/Database/RawSql.php
+++ b/system/Database/RawSql.php
@@ -11,10 +11,12 @@
 
 namespace CodeIgniter\Database;
 
+use Stringable;
+
 /**
  * @see \CodeIgniter\Database\RawSqlTest
  */
-class RawSql
+class RawSql implements Stringable
 {
     /**
      * @var string Raw SQL string
diff --git a/system/Database/SQLSRV/Builder.php b/system/Database/SQLSRV/Builder.php
index 5e3e4a73bb11..b2c207f6dc3f 100755
--- a/system/Database/SQLSRV/Builder.php
+++ b/system/Database/SQLSRV/Builder.php
@@ -69,7 +69,7 @@ protected function _fromTables(): string
         $from = [];
 
         foreach ($this->QBFrom as $value) {
-            $from[] = strpos($value, '(SELECT') === 0 ? $value : $this->getFullName($value);
+            $from[] = str_starts_with($value, '(SELECT') ? $value : $this->getFullName($value);
         }
 
         return implode(', ', $from);
@@ -280,7 +280,7 @@ private function getFullName(string $table): string
     {
         $alias = '';
 
-        if (strpos($table, ' ') !== false) {
+        if (str_contains($table, ' ')) {
             $alias = explode(' ', $table);
             $table = array_shift($alias);
             $alias = ' ' . implode(' ', $alias);
@@ -439,7 +439,7 @@ protected function maxMinAvgSum(string $select = '', string $alias = '', string
             throw DataException::forEmptyInputGiven('Select');
         }
 
-        if (strpos($select, ',') !== false) {
+        if (str_contains($select, ',')) {
             throw DataException::forInvalidArgument('Column name not separated by comma');
         }
 
diff --git a/system/Database/SQLSRV/Connection.php b/system/Database/SQLSRV/Connection.php
index f1a9fb0b433a..784f527790a1 100755
--- a/system/Database/SQLSRV/Connection.php
+++ b/system/Database/SQLSRV/Connection.php
@@ -121,7 +121,7 @@ public function connect(bool $persistent = false)
             unset($connection['UID'], $connection['PWD']);
         }
 
-        if (strpos($this->hostname, ',') === false && $this->port !== '') {
+        if (! str_contains($this->hostname, ',') && $this->port !== '') {
             $this->hostname .= ', ' . $this->port;
         }
 
@@ -253,10 +253,10 @@ protected function _indexData(string $table): array
             $_fields     = explode(',', trim($row->index_keys));
             $obj->fields = array_map(static fn ($v) => trim($v), $_fields);
 
-            if (strpos($row->index_description, 'primary key located on') !== false) {
+            if (str_contains($row->index_description, 'primary key located on')) {
                 $obj->type = 'PRIMARY';
             } else {
-                $obj->type = (strpos($row->index_description, 'nonclustered, unique') !== false) ? 'UNIQUE' : 'INDEX';
+                $obj->type = (str_contains($row->index_description, 'nonclustered, unique')) ? 'UNIQUE' : 'INDEX';
             }
 
             $retVal[$obj->name] = $obj;
diff --git a/system/Database/SQLite3/Connection.php b/system/Database/SQLite3/Connection.php
index f41c8e4de792..dcebba75a9ab 100644
--- a/system/Database/SQLite3/Connection.php
+++ b/system/Database/SQLite3/Connection.php
@@ -81,7 +81,7 @@ public function connect(bool $persistent = false)
         }
 
         try {
-            if ($this->database !== ':memory:' && strpos($this->database, DIRECTORY_SEPARATOR) === false) {
+            if ($this->database !== ':memory:' && ! str_contains($this->database, DIRECTORY_SEPARATOR)) {
                 $this->database = WRITEPATH . $this->database;
             }
 
diff --git a/system/Database/SQLite3/Forge.php b/system/Database/SQLite3/Forge.php
index b1dcb1dd599b..6487c94bbc4c 100644
--- a/system/Database/SQLite3/Forge.php
+++ b/system/Database/SQLite3/Forge.php
@@ -143,7 +143,7 @@ protected function _alterTable(string $alterType, string $table, $field)
      */
     protected function _processColumn(array $field): string
     {
-        if ($field['type'] === 'TEXT' && strpos($field['length'], "('") === 0) {
+        if ($field['type'] === 'TEXT' && str_starts_with($field['length'], "('")) {
             $field['type'] .= ' CHECK(' . $this->db->escapeIdentifiers($field['name'])
                 . ' IN ' . $field['length'] . ')';
         }
diff --git a/system/Database/SQLite3/Table.php b/system/Database/SQLite3/Table.php
index 879437da6f6a..9d3d1034119c 100644
--- a/system/Database/SQLite3/Table.php
+++ b/system/Database/SQLite3/Table.php
@@ -96,7 +96,7 @@ public function fromTable(string $table)
 
         $prefix = $this->db->DBPrefix;
 
-        if (! empty($prefix) && strpos($table, $prefix) === 0) {
+        if (! empty($prefix) && str_starts_with($table, $prefix)) {
             $table = substr($table, strlen($prefix));
         }
 
diff --git a/system/Database/Seeder.php b/system/Database/Seeder.php
index 749f6f34d5c7..ebd65e5a0387 100644
--- a/system/Database/Seeder.php
+++ b/system/Database/Seeder.php
@@ -123,7 +123,7 @@ public function call(string $class)
             throw new InvalidArgumentException('No seeder was specified.');
         }
 
-        if (strpos($class, '\\') === false) {
+        if (! str_contains($class, '\\')) {
             $path = $this->seedPath . str_replace('.php', '', $class) . '.php';
 
             if (! is_file($path)) {
diff --git a/system/Debug/BaseExceptionHandler.php b/system/Debug/BaseExceptionHandler.php
index 8b67d2153f9f..fcd6429b07d2 100644
--- a/system/Debug/BaseExceptionHandler.php
+++ b/system/Debug/BaseExceptionHandler.php
@@ -81,8 +81,8 @@ protected function collectVars(Throwable $exception, int $statusCode): array
         }
 
         return [
-            'title'   => get_class($exception),
-            'type'    => get_class($exception),
+            'title'   => $exception::class,
+            'type'    => $exception::class,
             'code'    => $statusCode,
             'message' => $exception->getMessage(),
             'file'    => $exception->getFile(),
@@ -114,7 +114,7 @@ private function maskData($args, array $keysToMask, string $path = '')
             $explode = explode('/', $keyToMask);
             $index   = end($explode);
 
-            if (strpos(strrev($path . '/' . $index), strrev($keyToMask)) === 0) {
+            if (str_starts_with(strrev($path . '/' . $index), strrev($keyToMask))) {
                 if (is_array($args) && array_key_exists($index, $args)) {
                     $args[$index] = '******************';
                 } elseif (
@@ -176,7 +176,7 @@ protected static function highlightFile(string $file, int $lineNumber, int $line
 
         try {
             $source = file_get_contents($file);
-        } catch (Throwable $e) {
+        } catch (Throwable) {
             return false;
         }
 
diff --git a/system/Debug/ExceptionHandler.php b/system/Debug/ExceptionHandler.php
index 63449888ffb5..51e85db3013c 100644
--- a/system/Debug/ExceptionHandler.php
+++ b/system/Debug/ExceptionHandler.php
@@ -54,7 +54,7 @@ public function handle(
         if ($request instanceof IncomingRequest) {
             try {
                 $response->setStatusCode($statusCode);
-            } catch (HTTPException $e) {
+            } catch (HTTPException) {
                 // Workaround for invalid HTTP status code.
                 $statusCode = 500;
                 $response->setStatusCode($statusCode);
@@ -73,7 +73,7 @@ public function handle(
                 );
             }
 
-            if (strpos($request->getHeaderLine('accept'), 'text/html') === false) {
+            if (! str_contains($request->getHeaderLine('accept'), 'text/html')) {
                 $data = (ENVIRONMENT === 'development' || ENVIRONMENT === 'testing')
                     ? $this->collectVars($exception, $statusCode)
                     : '';
diff --git a/system/Debug/Exceptions.php b/system/Debug/Exceptions.php
index da5ce9373753..0c00db0e40e1 100644
--- a/system/Debug/Exceptions.php
+++ b/system/Debug/Exceptions.php
@@ -173,7 +173,7 @@ public function exceptionHandler(Throwable $exception)
         if (! is_cli()) {
             try {
                 $this->response->setStatusCode($statusCode);
-            } catch (HTTPException $e) {
+            } catch (HTTPException) {
                 // Workaround for invalid HTTP status code.
                 $statusCode = 500;
                 $this->response->setStatusCode($statusCode);
@@ -183,7 +183,7 @@ public function exceptionHandler(Throwable $exception)
                 header(sprintf('HTTP/%s %s %s', $this->request->getProtocolVersion(), $this->response->getStatusCode(), $this->response->getReasonPhrase()), true, $statusCode);
             }
 
-            if (strpos($this->request->getHeaderLine('accept'), 'text/html') === false) {
+            if (! str_contains($this->request->getHeaderLine('accept'), 'text/html')) {
                 $this->respond(ENVIRONMENT === 'development' ? $this->collectVars($exception, $statusCode) : '', $statusCode)->send();
 
                 exit($exitCode);
@@ -241,7 +241,7 @@ public function shutdownHandler()
 
         if ($this->exceptionCaughtByExceptionHandler instanceof Throwable) {
             $message .= "\n【Previous Exception】\n"
-                . get_class($this->exceptionCaughtByExceptionHandler) . "\n"
+                . $this->exceptionCaughtByExceptionHandler::class . "\n"
                 . $this->exceptionCaughtByExceptionHandler->getMessage() . "\n"
                 . $this->exceptionCaughtByExceptionHandler->getTraceAsString();
         }
@@ -353,8 +353,8 @@ protected function collectVars(Throwable $exception, int $statusCode): array
         }
 
         return [
-            'title'   => get_class($exception),
-            'type'    => get_class($exception),
+            'title'   => $exception::class,
+            'type'    => $exception::class,
             'code'    => $statusCode,
             'message' => $exception->getMessage(),
             'file'    => $exception->getFile(),
@@ -394,7 +394,7 @@ private function maskData($args, array $keysToMask, string $path = '')
             $explode = explode('/', $keyToMask);
             $index   = end($explode);
 
-            if (strpos(strrev($path . '/' . $index), strrev($keyToMask)) === 0) {
+            if (str_starts_with(strrev($path . '/' . $index), strrev($keyToMask))) {
                 if (is_array($args) && array_key_exists($index, $args)) {
                     $args[$index] = '******************';
                 } elseif (
@@ -478,25 +478,13 @@ private function handleDeprecationError(string $message, ?string $file = null, ?
      */
     public static function cleanPath(string $file): string
     {
-        switch (true) {
-            case strpos($file, APPPATH) === 0:
-                $file = 'APPPATH' . DIRECTORY_SEPARATOR . substr($file, strlen(APPPATH));
-                break;
-
-            case strpos($file, SYSTEMPATH) === 0:
-                $file = 'SYSTEMPATH' . DIRECTORY_SEPARATOR . substr($file, strlen(SYSTEMPATH));
-                break;
-
-            case strpos($file, FCPATH) === 0:
-                $file = 'FCPATH' . DIRECTORY_SEPARATOR . substr($file, strlen(FCPATH));
-                break;
-
-            case defined('VENDORPATH') && strpos($file, VENDORPATH) === 0:
-                $file = 'VENDORPATH' . DIRECTORY_SEPARATOR . substr($file, strlen(VENDORPATH));
-                break;
-        }
-
-        return $file;
+        return match (true) {
+            str_starts_with($file, APPPATH)                             => 'APPPATH' . DIRECTORY_SEPARATOR . substr($file, strlen(APPPATH)),
+            str_starts_with($file, SYSTEMPATH)                          => 'SYSTEMPATH' . DIRECTORY_SEPARATOR . substr($file, strlen(SYSTEMPATH)),
+            str_starts_with($file, FCPATH)                              => 'FCPATH' . DIRECTORY_SEPARATOR . substr($file, strlen(FCPATH)),
+            defined('VENDORPATH') && str_starts_with($file, VENDORPATH) => 'VENDORPATH' . DIRECTORY_SEPARATOR . substr($file, strlen(VENDORPATH)),
+            default                                                     => $file,
+        };
     }
 
     /**
@@ -542,7 +530,7 @@ public static function highlightFile(string $file, int $lineNumber, int $lines =
 
         try {
             $source = file_get_contents($file);
-        } catch (Throwable $e) {
+        } catch (Throwable) {
             return false;
         }
 
@@ -607,23 +595,12 @@ private static function renderBacktrace(array $backtrace): string
             $idx = $index;
             $idx = str_pad((string) ++$idx, 2, ' ', STR_PAD_LEFT);
 
-            $args = implode(', ', array_map(static function ($value): string {
-                switch (true) {
-                    case is_object($value):
-                        return sprintf('Object(%s)', get_class($value));
-
-                    case is_array($value):
-                        return $value !== [] ? '[...]' : '[]';
-
-                    case $value === null:
-                        return 'null';
-
-                    case is_resource($value):
-                        return sprintf('resource (%s)', get_resource_type($value));
-
-                    default:
-                        return var_export($value, true);
-                }
+            $args = implode(', ', array_map(static fn ($value): string => match (true) {
+                is_object($value)   => sprintf('Object(%s)', $value::class),
+                is_array($value)    => $value !== [] ? '[...]' : '[]',
+                $value === null     => 'null',
+                is_resource($value) => sprintf('resource (%s)', get_resource_type($value)),
+                default             => var_export($value, true),
             }, $frame['args']));
 
             $backtraces[] = sprintf(
diff --git a/system/Debug/Toolbar.php b/system/Debug/Toolbar.php
index 3f846a36d2e7..3cf0566cca07 100644
--- a/system/Debug/Toolbar.php
+++ b/system/Debug/Toolbar.php
@@ -408,7 +408,7 @@ public function prepare(?RequestInterface $request = null, ?ResponseInterface $r
             // Non-HTML formats should not include the debugbar
             // then we send headers saying where to find the debug data
             // for this response
-            if ($request->isAJAX() || strpos($format, 'html') === false) {
+            if ($request->isAJAX() || ! str_contains($format, 'html')) {
                 $response->setHeader('Debugbar-Time', "{$time}")
                     ->setHeader('Debugbar-Link', site_url("?debugbar_time={$time}"));
 
@@ -431,7 +431,7 @@ public function prepare(?RequestInterface $request = null, ?ResponseInterface $r
                 . $kintScript
                 . PHP_EOL;
 
-            if (strpos($response->getBody(), '<head>') !== false) {
+            if (str_contains($response->getBody(), '<head>')) {
                 $response->setBody(
                     preg_replace(
                         '/<head>/',
diff --git a/system/Debug/Toolbar/Collectors/Database.php b/system/Debug/Toolbar/Collectors/Database.php
index b527f2ed3c95..93178f95d9c2 100644
--- a/system/Debug/Toolbar/Collectors/Database.php
+++ b/system/Debug/Toolbar/Collectors/Database.php
@@ -161,7 +161,7 @@ public function display(): array
                 }
 
                 // find the first trace line that does not originate from `system/`
-                if ($firstNonSystemLine === '' && strpos($line['file'], 'SYSTEMPATH') === false) {
+                if ($firstNonSystemLine === '' && ! str_contains($line['file'], 'SYSTEMPATH')) {
                     $firstNonSystemLine = $line['file'];
                 }
 
diff --git a/system/Debug/Toolbar/Collectors/Files.php b/system/Debug/Toolbar/Collectors/Files.php
index c281906cdd28..4461b4b667d8 100644
--- a/system/Debug/Toolbar/Collectors/Files.php
+++ b/system/Debug/Toolbar/Collectors/Files.php
@@ -60,7 +60,7 @@ public function display(): array
         foreach ($rawFiles as $file) {
             $path = clean_path($file);
 
-            if (strpos($path, 'SYSTEMPATH') !== false) {
+            if (str_contains($path, 'SYSTEMPATH')) {
                 $coreFiles[] = [
                     'path' => $path,
                     'name' => basename($file),
diff --git a/system/Debug/Toolbar/Collectors/Routes.php b/system/Debug/Toolbar/Collectors/Routes.php
index 46aa91644004..c80ef7948fdf 100644
--- a/system/Debug/Toolbar/Collectors/Routes.php
+++ b/system/Debug/Toolbar/Collectors/Routes.php
@@ -63,7 +63,7 @@ public function display(): array
         } else {
             try {
                 $method = new ReflectionMethod($router->controllerName(), $router->methodName());
-            } catch (ReflectionException $e) {
+            } catch (ReflectionException) {
                 try {
                     // If we're here, the method doesn't exist
                     // and is likely calculated in _remap.
diff --git a/system/Email/Email.php b/system/Email/Email.php
index 27e5bc83b683..9246da0cd794 100644
--- a/system/Email/Email.php
+++ b/system/Email/Email.php
@@ -658,7 +658,7 @@ public function setMessage($body)
     public function attach($file, $disposition = '', $newname = null, $mime = '')
     {
         if ($mime === '') {
-            if (strpos($file, '://') === false && ! is_file($file)) {
+            if (! str_contains($file, '://') && ! is_file($file)) {
                 $this->setErrorMessage(lang('Email.attachmentMissing', [$file]));
 
                 return false;
@@ -738,7 +738,7 @@ public function setHeader($header, $value)
     protected function stringToArray($email)
     {
         if (! is_array($email)) {
-            return (strpos($email, ',') !== false) ? preg_split('/[\s,]/', $email, -1, PREG_SPLIT_NO_EMPTY) : (array) trim($email);
+            return (str_contains($email, ',')) ? preg_split('/[\s,]/', $email, -1, PREG_SPLIT_NO_EMPTY) : (array) trim($email);
         }
 
         return $email;
@@ -862,7 +862,7 @@ protected function getEncoding()
         }
 
         foreach ($this->baseCharsets as $charset) {
-            if (strpos($this->charset, $charset) === 0) {
+            if (str_starts_with($this->charset, $charset)) {
                 $this->encoding = '7bit';
 
                 break;
@@ -1011,7 +1011,7 @@ public function wordWrap($str, $charlim = null)
             $charlim = empty($this->wrapChars) ? 76 : $this->wrapChars;
         }
 
-        if (strpos($str, "\r") !== false) {
+        if (str_contains($str, "\r")) {
             $str = str_replace(["\r\n", "\r"], "\n", $str);
         }
 
@@ -1409,7 +1409,7 @@ protected function prepQuotedPrintable($str)
         $str = preg_replace(['| +|', '/\x00+/'], [' ', ''], $str);
 
         // Standardize newlines
-        if (strpos($str, "\r") !== false) {
+        if (str_contains($str, "\r")) {
             $str = str_replace(["\r\n", "\r"], "\n", $str);
         }
 
@@ -1661,7 +1661,7 @@ protected function unwrapSpecials()
      */
     protected function removeNLCallback($matches)
     {
-        if (strpos($matches[1], "\r") !== false || strpos($matches[1], "\n") !== false) {
+        if (str_contains($matches[1], "\r") || str_contains($matches[1], "\n")) {
             $matches[1] = str_replace(["\r\n", "\r", "\n"], '', $matches[1]);
         }
 
@@ -1842,7 +1842,7 @@ protected function sendWithSmtp()
         $this->setErrorMessage($reply);
         $this->SMTPEnd();
 
-        if (strpos($reply, '250') !== 0) {
+        if (! str_starts_with($reply, '250')) {
             $this->setErrorMessage(lang('Email.SMTPError', [$reply]));
 
             return false;
@@ -2014,11 +2014,11 @@ protected function SMTPAuthenticate()
         $this->sendData('AUTH LOGIN');
         $reply = $this->getSMTPData();
 
-        if (strpos($reply, '503') === 0) {    // Already authenticated
+        if (str_starts_with($reply, '503')) {    // Already authenticated
             return true;
         }
 
-        if (strpos($reply, '334') !== 0) {
+        if (! str_starts_with($reply, '334')) {
             $this->setErrorMessage(lang('Email.failedSMTPLogin', [$reply]));
 
             return false;
@@ -2027,7 +2027,7 @@ protected function SMTPAuthenticate()
         $this->sendData(base64_encode($this->SMTPUser));
         $reply = $this->getSMTPData();
 
-        if (strpos($reply, '334') !== 0) {
+        if (! str_starts_with($reply, '334')) {
             $this->setErrorMessage(lang('Email.SMTPAuthUsername', [$reply]));
 
             return false;
@@ -2036,7 +2036,7 @@ protected function SMTPAuthenticate()
         $this->sendData(base64_encode($this->SMTPPass));
         $reply = $this->getSMTPData();
 
-        if (strpos($reply, '235') !== 0) {
+        if (! str_starts_with($reply, '235')) {
             $this->setErrorMessage(lang('Email.SMTPAuthPassword', [$reply]));
 
             return false;
diff --git a/system/Entity/Cast/ArrayCast.php b/system/Entity/Cast/ArrayCast.php
index 315f2e582fec..d68d17c187de 100644
--- a/system/Entity/Cast/ArrayCast.php
+++ b/system/Entity/Cast/ArrayCast.php
@@ -21,7 +21,7 @@ class ArrayCast extends BaseCast
      */
     public static function get($value, array $params = []): array
     {
-        if (is_string($value) && (strpos($value, 'a:') === 0 || strpos($value, 's:') === 0)) {
+        if (is_string($value) && (str_starts_with($value, 'a:') || str_starts_with($value, 's:'))) {
             $value = unserialize($value);
         }
 
diff --git a/system/Entity/Entity.php b/system/Entity/Entity.php
index 90d3ab46a297..12db7a97a059 100644
--- a/system/Entity/Entity.php
+++ b/system/Entity/Entity.php
@@ -167,7 +167,7 @@ public function toArray(bool $onlyChanged = false, bool $cast = true, bool $recu
     {
         $this->_cast = $cast;
 
-        $keys = array_filter(array_keys($this->attributes), static fn ($key) => strpos($key, '_') !== 0);
+        $keys = array_filter(array_keys($this->attributes), static fn ($key) => ! str_starts_with($key, '_'));
 
         if (is_array($this->datamap)) {
             $keys = array_unique(
@@ -368,7 +368,7 @@ protected function castAs($value, string $attribute, string $method = 'get')
 
         $isNullable = false;
 
-        if (strpos($type, '?') === 0) {
+        if (str_starts_with($type, '?')) {
             $isNullable = true;
 
             if ($value === null) {
diff --git a/system/Entity/Exceptions/CastException.php b/system/Entity/Exceptions/CastException.php
index e259447b3f76..4bcb62be8067 100644
--- a/system/Entity/Exceptions/CastException.php
+++ b/system/Entity/Exceptions/CastException.php
@@ -41,25 +41,14 @@ public static function forInvalidInterface(string $class)
      */
     public static function forInvalidJsonFormat(int $error)
     {
-        switch ($error) {
-            case JSON_ERROR_DEPTH:
-                return new static(lang('Cast.jsonErrorDepth'));
-
-            case JSON_ERROR_STATE_MISMATCH:
-                return new static(lang('Cast.jsonErrorStateMismatch'));
-
-            case JSON_ERROR_CTRL_CHAR:
-                return new static(lang('Cast.jsonErrorCtrlChar'));
-
-            case JSON_ERROR_SYNTAX:
-                return new static(lang('Cast.jsonErrorSyntax'));
-
-            case JSON_ERROR_UTF8:
-                return new static(lang('Cast.jsonErrorUtf8'));
-
-            default:
-                return new static(lang('Cast.jsonErrorUnknown'));
-        }
+        return match ($error) {
+            JSON_ERROR_DEPTH          => new static(lang('Cast.jsonErrorDepth')),
+            JSON_ERROR_STATE_MISMATCH => new static(lang('Cast.jsonErrorStateMismatch')),
+            JSON_ERROR_CTRL_CHAR      => new static(lang('Cast.jsonErrorCtrlChar')),
+            JSON_ERROR_SYNTAX         => new static(lang('Cast.jsonErrorSyntax')),
+            JSON_ERROR_UTF8           => new static(lang('Cast.jsonErrorUtf8')),
+            default                   => new static(lang('Cast.jsonErrorUnknown')),
+        };
     }
 
     /**
diff --git a/system/Exceptions/CastException.php b/system/Exceptions/CastException.php
index 8dfb29543a78..e316f8726d9a 100644
--- a/system/Exceptions/CastException.php
+++ b/system/Exceptions/CastException.php
@@ -32,24 +32,13 @@ public function getExitCode(): int
      */
     public static function forInvalidJsonFormatException(int $error)
     {
-        switch ($error) {
-            case JSON_ERROR_DEPTH:
-                return new static(lang('Cast.jsonErrorDepth'));
-
-            case JSON_ERROR_STATE_MISMATCH:
-                return new static(lang('Cast.jsonErrorStateMismatch'));
-
-            case JSON_ERROR_CTRL_CHAR:
-                return new static(lang('Cast.jsonErrorCtrlChar'));
-
-            case JSON_ERROR_SYNTAX:
-                return new static(lang('Cast.jsonErrorSyntax'));
-
-            case JSON_ERROR_UTF8:
-                return new static(lang('Cast.jsonErrorUtf8'));
-
-            default:
-                return new static(lang('Cast.jsonErrorUnknown'));
-        }
+        return match ($error) {
+            JSON_ERROR_DEPTH          => new static(lang('Cast.jsonErrorDepth')),
+            JSON_ERROR_STATE_MISMATCH => new static(lang('Cast.jsonErrorStateMismatch')),
+            JSON_ERROR_CTRL_CHAR      => new static(lang('Cast.jsonErrorCtrlChar')),
+            JSON_ERROR_SYNTAX         => new static(lang('Cast.jsonErrorSyntax')),
+            JSON_ERROR_UTF8           => new static(lang('Cast.jsonErrorUtf8')),
+            default                   => new static(lang('Cast.jsonErrorUnknown')),
+        };
     }
 }
diff --git a/system/Exceptions/FrameworkException.php b/system/Exceptions/FrameworkException.php
index faf3f1480126..83f9cb2808b6 100644
--- a/system/Exceptions/FrameworkException.php
+++ b/system/Exceptions/FrameworkException.php
@@ -60,7 +60,7 @@ public static function forCopyError(string $path)
      */
     public static function forMissingExtension(string $extension)
     {
-        if (strpos($extension, 'intl') !== false) {
+        if (str_contains($extension, 'intl')) {
             // @codeCoverageIgnoreStart
             $message = sprintf(
                 'The framework needs the following extension(s) installed and loaded: %s.',
diff --git a/system/Files/File.php b/system/Files/File.php
index 4e4ee388047e..d0842fb6bb7a 100644
--- a/system/Files/File.php
+++ b/system/Files/File.php
@@ -74,16 +74,11 @@ public function getSize()
      */
     public function getSizeByUnit(string $unit = 'b')
     {
-        switch (strtolower($unit)) {
-            case 'kb':
-                return number_format($this->getSize() / 1024, 3);
-
-            case 'mb':
-                return number_format(($this->getSize() / 1024) / 1024, 3);
-
-            default:
-                return $this->getSize();
-        }
+        return match (strtolower($unit)) {
+            'kb'    => number_format($this->getSize() / 1024, 3),
+            'mb'    => number_format(($this->getSize() / 1024) / 1024, 3),
+            default => $this->getSize(),
+        };
     }
 
     /**
@@ -173,7 +168,7 @@ public function getDestination(string $destination, string $delimiter = '_', int
             $info      = pathinfo($destination);
             $extension = isset($info['extension']) ? '.' . $info['extension'] : '';
 
-            if (strpos($info['filename'], $delimiter) !== false) {
+            if (str_contains($info['filename'], $delimiter)) {
                 $parts = explode($delimiter, $info['filename']);
 
                 if (is_numeric(end($parts))) {
diff --git a/system/Files/FileCollection.php b/system/Files/FileCollection.php
index 87f987eb8f1e..545f8997a3b0 100644
--- a/system/Files/FileCollection.php
+++ b/system/Files/FileCollection.php
@@ -83,7 +83,7 @@ final protected static function filterFiles(array $files, string $directory): ar
     {
         $directory = self::resolveDirectory($directory);
 
-        return array_filter($files, static fn (string $value): bool => strpos($value, $directory) === 0);
+        return array_filter($files, static fn (string $value): bool => str_starts_with($value, $directory));
     }
 
     /**
@@ -180,7 +180,7 @@ public function add($paths, bool $recursive = true)
             try {
                 // Test for a directory
                 self::resolveDirectory($path);
-            } catch (FileException $e) {
+            } catch (FileException) {
                 $this->addFile($path);
 
                 continue;
diff --git a/system/Filters/Filters.php b/system/Filters/Filters.php
index 25ca9a9ec5f7..6816e72ab482 100644
--- a/system/Filters/Filters.php
+++ b/system/Filters/Filters.php
@@ -192,7 +192,7 @@ private function runBefore(array $filterClasses)
             $class = new $className();
 
             if (! $class instanceof FilterInterface) {
-                throw FilterException::forIncorrectInterface(get_class($class));
+                throw FilterException::forIncorrectInterface($class::class);
             }
 
             $result = $class->before(
@@ -485,7 +485,7 @@ private function getCleanName(string $name): array
     {
         $arguments = [];
 
-        if (strpos($name, ':') !== false) {
+        if (str_contains($name, ':')) {
             [$name, $arguments] = explode(':', $name);
 
             $arguments = explode(',', $arguments);
diff --git a/system/HTTP/CURLRequest.php b/system/HTTP/CURLRequest.php
index 35b62ec3486f..a73796af42b4 100644
--- a/system/HTTP/CURLRequest.php
+++ b/system/HTTP/CURLRequest.php
@@ -323,7 +323,7 @@ protected function parseOptions(array $options)
     protected function prepareURL(string $url): string
     {
         // If it's a full URI, then we have nothing to do here...
-        if (strpos($url, '://') !== false) {
+        if (str_contains($url, '://')) {
             return $url;
         }
 
@@ -378,16 +378,16 @@ public function send(string $method, string $url)
         // Set the string we want to break our response from
         $breakString = "\r\n\r\n";
 
-        if (strpos($output, 'HTTP/1.1 100 Continue') === 0) {
+        if (str_starts_with($output, 'HTTP/1.1 100 Continue')) {
             $output = substr($output, strpos($output, $breakString) + 4);
         }
 
-        if (strpos($output, 'HTTP/1.1 200 Connection established') === 0) {
+        if (str_starts_with($output, 'HTTP/1.1 200 Connection established')) {
             $output = substr($output, strpos($output, $breakString) + 4);
         }
 
         // If request and response have Digest
-        if (isset($this->config['auth'][2]) && $this->config['auth'][2] === 'digest' && strpos($output, 'WWW-Authenticate: Digest') !== false) {
+        if (isset($this->config['auth'][2]) && $this->config['auth'][2] === 'digest' && str_contains($output, 'WWW-Authenticate: Digest')) {
             $output = substr($output, strpos($output, $breakString) + 4);
         }
 
@@ -487,7 +487,7 @@ protected function setResponseHeaders(array $headers = [])
                 } else {
                     $this->response->setHeader($title, $value);
                 }
-            } elseif (strpos($header, 'HTTP') === 0) {
+            } elseif (str_starts_with($header, 'HTTP')) {
                 preg_match('#^HTTP\/([12](?:\.[01])?) (\d+) (.+)#', $header, $matches);
 
                 if (isset($matches[1])) {
diff --git a/system/HTTP/ContentSecurityPolicy.php b/system/HTTP/ContentSecurityPolicy.php
index 6a3caed925b8..82ee286716e7 100644
--- a/system/HTTP/ContentSecurityPolicy.php
+++ b/system/HTTP/ContentSecurityPolicy.php
@@ -800,7 +800,7 @@ protected function addToHeader(string $name, $values = null)
                 $reportOnly = $this->reportOnly;
             }
 
-            if (strpos($value, 'nonce-') === 0) {
+            if (str_starts_with($value, 'nonce-')) {
                 $value = "'{$value}'";
             }
 
diff --git a/system/HTTP/Files/FileCollection.php b/system/HTTP/Files/FileCollection.php
index 7188d357b006..6de5f2d0f80d 100644
--- a/system/HTTP/Files/FileCollection.php
+++ b/system/HTTP/Files/FileCollection.php
@@ -57,7 +57,7 @@ public function getFile(string $name)
         $this->populateFiles();
 
         if ($this->hasFile($name)) {
-            if (strpos($name, '.') !== false) {
+            if (str_contains($name, '.')) {
                 $name         = explode('.', $name);
                 $uploadedFile = $this->getValueDotNotationSyntax($name, $this->files);
 
@@ -84,7 +84,7 @@ public function getFileMultiple(string $name)
         $this->populateFiles();
 
         if ($this->hasFile($name)) {
-            if (strpos($name, '.') !== false) {
+            if (str_contains($name, '.')) {
                 $name         = explode('.', $name);
                 $uploadedFile = $this->getValueDotNotationSyntax($name, $this->files);
 
@@ -113,7 +113,7 @@ public function hasFile(string $fileID): bool
     {
         $this->populateFiles();
 
-        if (strpos($fileID, '.') !== false) {
+        if (str_contains($fileID, '.')) {
             $segments = explode('.', $fileID);
 
             $el = $this->files;
diff --git a/system/HTTP/Files/UploadedFile.php b/system/HTTP/Files/UploadedFile.php
index 70ece748d834..b81881c62cb3 100644
--- a/system/HTTP/Files/UploadedFile.php
+++ b/system/HTTP/Files/UploadedFile.php
@@ -151,7 +151,7 @@ public function move(string $targetPath, ?string $name = null, bool $overwrite =
 
         try {
             $this->hasMoved = move_uploaded_file($this->path, $destination);
-        } catch (Exception $e) {
+        } catch (Exception) {
             $error   = error_get_last();
             $message = strip_tags($error['message'] ?? '');
 
diff --git a/system/HTTP/Header.php b/system/HTTP/Header.php
index b152509a1cee..0c27e65dbb33 100644
--- a/system/HTTP/Header.php
+++ b/system/HTTP/Header.php
@@ -11,6 +11,8 @@
 
 namespace CodeIgniter\HTTP;
 
+use Stringable;
+
 /**
  * Class Header
  *
@@ -18,7 +20,7 @@
  *
  * @see \CodeIgniter\HTTP\HeaderTest
  */
-class Header
+class Header implements Stringable
 {
     /**
      * The name of the header.
diff --git a/system/HTTP/IncomingRequest.php b/system/HTTP/IncomingRequest.php
index ee5aa8bd6ca0..be1342a9e94c 100755
--- a/system/HTTP/IncomingRequest.php
+++ b/system/HTTP/IncomingRequest.php
@@ -158,7 +158,7 @@ public function __construct($config, ?URI $uri = null, $body = 'php://input', ?U
             $body === 'php://input'
             // php://input is not available with enctype="multipart/form-data".
             // See https://www.php.net/manual/en/wrappers.php.php#wrappers.php.input
-            && strpos($this->getHeaderLine('Content-Type'), 'multipart/form-data') === false
+            && ! str_contains($this->getHeaderLine('Content-Type'), 'multipart/form-data')
             && (int) $this->getHeaderLine('Content-Length') <= $this->getPostMaxSize()
         ) {
             // Get our body from php://input
@@ -191,24 +191,12 @@ private function getPostMaxSize(): int
     {
         $postMaxSize = ini_get('post_max_size');
 
-        switch (strtoupper(substr($postMaxSize, -1))) {
-            case 'G':
-                $postMaxSize = (int) str_replace('G', '', $postMaxSize) * 1024 ** 3;
-                break;
-
-            case 'M':
-                $postMaxSize = (int) str_replace('M', '', $postMaxSize) * 1024 ** 2;
-                break;
-
-            case 'K':
-                $postMaxSize = (int) str_replace('K', '', $postMaxSize) * 1024;
-                break;
-
-            default:
-                $postMaxSize = (int) $postMaxSize;
-        }
-
-        return $postMaxSize;
+        return match (strtoupper(substr($postMaxSize, -1))) {
+            'G'     => (int) str_replace('G', '', $postMaxSize) * 1024 ** 3,
+            'M'     => (int) str_replace('M', '', $postMaxSize) * 1024 ** 2,
+            'K'     => (int) str_replace('K', '', $postMaxSize) * 1024,
+            default => (int) $postMaxSize,
+        };
     }
 
     /**
@@ -256,20 +244,11 @@ public function detectPath(string $protocol = ''): string
             $protocol = 'REQUEST_URI';
         }
 
-        switch ($protocol) {
-            case 'REQUEST_URI':
-                $this->path = $this->parseRequestURI();
-                break;
-
-            case 'QUERY_STRING':
-                $this->path = $this->parseQueryString();
-                break;
-
-            case 'PATH_INFO':
-            default:
-                $this->path = $this->fetchGlobal('server', $protocol) ?? $this->parseRequestURI();
-                break;
-        }
+        $this->path = match ($protocol) {
+            'REQUEST_URI'  => $this->parseRequestURI(),
+            'QUERY_STRING' => $this->parseQueryString(),
+            default        => $this->fetchGlobal('server', $protocol) ?? $this->parseRequestURI(),
+        };
 
         return $this->path;
     }
@@ -317,7 +296,7 @@ protected function parseRequestURI(): string
 
         // This section ensures that even on servers that require the URI to contain the query string (Nginx) a correct
         // URI is found, and also fixes the QUERY_STRING Server var and $_GET array.
-        if (trim($uri, '/') === '' && strncmp($query, '/', 1) === 0) {
+        if (trim($uri, '/') === '' && str_starts_with($query, '/')) {
             $query                   = explode('?', $query, 2);
             $uri                     = $query[0];
             $_SERVER['QUERY_STRING'] = $query[1] ?? '';
@@ -350,7 +329,7 @@ protected function parseQueryString(): string
             return '/';
         }
 
-        if (strncmp($uri, '/', 1) === 0) {
+        if (str_starts_with($uri, '/')) {
             $uri                     = explode('?', $uri, 2);
             $_SERVER['QUERY_STRING'] = $uri[1] ?? '';
             $uri                     = $uri[0];
@@ -376,21 +355,13 @@ public function negotiate(string $type, array $supported, bool $strictMatch = fa
             $this->negotiator = Services::negotiator($this, true);
         }
 
-        switch (strtolower($type)) {
-            case 'media':
-                return $this->negotiator->media($supported, $strictMatch);
-
-            case 'charset':
-                return $this->negotiator->charset($supported);
-
-            case 'encoding':
-                return $this->negotiator->encoding($supported);
-
-            case 'language':
-                return $this->negotiator->language($supported);
-        }
-
-        throw HTTPException::forInvalidNegotiationType($type);
+        return match (strtolower($type)) {
+            'media'    => $this->negotiator->media($supported, $strictMatch),
+            'charset'  => $this->negotiator->charset($supported),
+            'encoding' => $this->negotiator->encoding($supported),
+            'language' => $this->negotiator->language($supported),
+            default    => throw HTTPException::forInvalidNegotiationType($type),
+        };
     }
 
     /**
@@ -410,7 +381,7 @@ public function is(string $type): bool
         }
 
         if ($valueUpper === 'JSON') {
-            return strpos($this->getHeaderLine('Content-Type'), 'application/json') !== false;
+            return str_contains($this->getHeaderLine('Content-Type'), 'application/json');
         }
 
         if ($valueUpper === 'AJAX') {
@@ -546,7 +517,7 @@ public function getDefaultLocale(): string
     public function getVar($index = null, $filter = null, $flags = null)
     {
         if (
-            strpos($this->getHeaderLine('Content-Type'), 'application/json') !== false
+            str_contains($this->getHeaderLine('Content-Type'), 'application/json')
             && $this->body !== null
         ) {
             return $this->getJsonVar($index, false, $filter, $flags);
diff --git a/system/HTTP/RedirectResponse.php b/system/HTTP/RedirectResponse.php
index 8efd4c2c51ea..9c406df504cf 100644
--- a/system/HTTP/RedirectResponse.php
+++ b/system/HTTP/RedirectResponse.php
@@ -35,7 +35,7 @@ public function to(string $uri, ?int $code = null, string $method = 'auto')
     {
         // If it appears to be a relative URL, then convert to full URL
         // for better security.
-        if (strpos($uri, 'http') !== 0) {
+        if (! str_starts_with($uri, 'http')) {
             $uri = site_url($uri);
         }
 
diff --git a/system/HTTP/RequestTrait.php b/system/HTTP/RequestTrait.php
index 6db903ddacec..5609d786b23f 100644
--- a/system/HTTP/RequestTrait.php
+++ b/system/HTTP/RequestTrait.php
@@ -77,7 +77,7 @@ public function getIPAddress(): string
         // @TODO Extract all this IP address logic to another class.
         foreach ($proxyIPs as $proxyIP => $header) {
             // Check if we have an IP address or a subnet
-            if (strpos($proxyIP, '/') === false) {
+            if (! str_contains($proxyIP, '/')) {
                 // An IP address (and not a subnet) is specified.
                 // We can compare right away.
                 if ($proxyIP === $this->ipAddress) {
@@ -98,7 +98,7 @@ public function getIPAddress(): string
             }
 
             // If the proxy entry doesn't match the IP protocol - skip it
-            if (strpos($proxyIP, $separator) === false) {
+            if (! str_contains($proxyIP, $separator)) {
                 continue;
             }
 
diff --git a/system/HTTP/ResponseTrait.php b/system/HTTP/ResponseTrait.php
index e5e006c776aa..e93d4279a428 100644
--- a/system/HTTP/ResponseTrait.php
+++ b/system/HTTP/ResponseTrait.php
@@ -447,7 +447,7 @@ public function redirect(string $uri, string $method = 'auto', ?int $code = null
         if (
             $method === 'auto'
             && isset($_SERVER['SERVER_SOFTWARE'])
-            && strpos($_SERVER['SERVER_SOFTWARE'], 'Microsoft-IIS') !== false
+            && str_contains($_SERVER['SERVER_SOFTWARE'], 'Microsoft-IIS')
         ) {
             $method = 'refresh';
         } elseif ($method !== 'refresh' && $code === null) {
@@ -471,15 +471,10 @@ public function redirect(string $uri, string $method = 'auto', ?int $code = null
             $code = 302;
         }
 
-        switch ($method) {
-            case 'refresh':
-                $this->setHeader('Refresh', '0;url=' . $uri);
-                break;
-
-            default:
-                $this->setHeader('Location', $uri);
-                break;
-        }
+        match ($method) {
+            'refresh' => $this->setHeader('Refresh', '0;url=' . $uri),
+            default   => $this->setHeader('Location', $uri),
+        };
 
         $this->setStatusCode($code);
 
diff --git a/system/HTTP/SiteURI.php b/system/HTTP/SiteURI.php
index 6d56507314e7..43948ecbf33c 100644
--- a/system/HTTP/SiteURI.php
+++ b/system/HTTP/SiteURI.php
@@ -15,13 +15,14 @@
 use CodeIgniter\Exceptions\ConfigException;
 use CodeIgniter\HTTP\Exceptions\HTTPException;
 use Config\App;
+use Stringable;
 
 /**
  * URI for the application site
  *
  * @see \CodeIgniter\HTTP\SiteURITest
  */
-class SiteURI extends URI
+class SiteURI extends URI implements Stringable
 {
     /**
      * The current baseURL.
diff --git a/system/HTTP/SiteURIFactory.php b/system/HTTP/SiteURIFactory.php
index 36b9d705b28c..fd4921be913c 100644
--- a/system/HTTP/SiteURIFactory.php
+++ b/system/HTTP/SiteURIFactory.php
@@ -95,20 +95,11 @@ public function detectRoutePath(string $protocol = ''): string
             $protocol = $this->appConfig->uriProtocol;
         }
 
-        switch ($protocol) {
-            case 'REQUEST_URI':
-                $routePath = $this->parseRequestURI();
-                break;
-
-            case 'QUERY_STRING':
-                $routePath = $this->parseQueryString();
-                break;
-
-            case 'PATH_INFO':
-            default:
-                $routePath = $this->superglobals->server($protocol) ?? $this->parseRequestURI();
-                break;
-        }
+        $routePath = match ($protocol) {
+            'REQUEST_URI'  => $this->parseRequestURI(),
+            'QUERY_STRING' => $this->parseQueryString(),
+            default        => $this->superglobals->server($protocol) ?? $this->parseRequestURI(),
+        };
 
         return ($routePath === '/' || $routePath === '') ? '/' : ltrim($routePath, '/');
     }
@@ -161,7 +152,7 @@ private function parseRequestURI(): string
         // This section ensures that even on servers that require the URI to
         // contain the query string (Nginx) a correct URI is found, and also
         // fixes the QUERY_STRING Server var and $_GET array.
-        if (trim($path, '/') === '' && strncmp($query, '/', 1) === 0) {
+        if (trim($path, '/') === '' && str_starts_with($query, '/')) {
             $parts    = explode('?', $query, 2);
             $path     = $parts[0];
             $newQuery = $query[1] ?? '';
@@ -193,7 +184,7 @@ private function parseQueryString(): string
             return '/';
         }
 
-        if (strncmp($query, '/', 1) === 0) {
+        if (str_starts_with($query, '/')) {
             $parts    = explode('?', $query, 2);
             $path     = $parts[0];
             $newQuery = $parts[1] ?? '';
diff --git a/system/HTTP/URI.php b/system/HTTP/URI.php
index 608f8b75d5ba..7d1913da8229 100644
--- a/system/HTTP/URI.php
+++ b/system/HTTP/URI.php
@@ -15,13 +15,14 @@
 use CodeIgniter\HTTP\Exceptions\HTTPException;
 use Config\App;
 use InvalidArgumentException;
+use Stringable;
 
 /**
  * Abstraction for a uniform resource identifier (URI).
  *
  * @see \CodeIgniter\HTTP\URITest
  */
-class URI
+class URI implements Stringable
 {
     /**
      * Sub-delimiters used in query strings and fragments.
@@ -172,7 +173,7 @@ public static function createURIString(
         }
 
         if (isset($path) && $path !== '') {
-            $uri .= substr($uri, -1, 1) !== '/'
+            $uri .= ! str_ends_with($uri, '/')
                 ? '/' . ltrim($path, '/')
                 : ltrim($path, '/');
         }
@@ -228,12 +229,12 @@ public static function removeDotSegments(string $path): string
         $output = trim($output, '/ ');
 
         // Add leading slash if necessary
-        if (strpos($path, '/') === 0) {
+        if (str_starts_with($path, '/')) {
             $output = '/' . $output;
         }
 
         // Add trailing slash if necessary
-        if ($output !== '/' && substr($path, -1, 1) === '/') {
+        if ($output !== '/' && str_ends_with($path, '/')) {
             $output .= '/';
         }
 
@@ -652,14 +653,14 @@ private function changeSchemeAndPath(string $scheme, string $path): array
         $baseUri = new self($config->baseURL);
 
         if (
-            substr($this->getScheme(), 0, 4) === 'http'
+            str_starts_with($this->getScheme(), 'http')
             && $this->getHost() === $baseUri->getHost()
         ) {
             // Check for additional segments
             $basePath = trim($baseUri->getPath(), '/') . '/';
             $trimPath = ltrim($path, '/');
 
-            if ($basePath !== '/' && strpos($trimPath, $basePath) !== 0) {
+            if ($basePath !== '/' && ! str_starts_with($trimPath, $basePath)) {
                 $path = $basePath . $trimPath;
             }
 
@@ -877,7 +878,7 @@ public function refreshPath()
      */
     public function setQuery(string $query)
     {
-        if (strpos($query, '#') !== false) {
+        if (str_contains($query, '#')) {
             if ($this->silent) {
                 return $this;
             }
@@ -886,7 +887,7 @@ public function setQuery(string $query)
         }
 
         // Can't have leading ?
-        if (! empty($query) && strpos($query, '?') === 0) {
+        if (! empty($query) && str_starts_with($query, '?')) {
             $query = substr($query, 1);
         }
 
@@ -1008,10 +1009,10 @@ protected function filterPath(?string $path = null): string
         $path = self::removeDotSegments($path);
 
         // Fix up some leading slash edge cases...
-        if (strpos($orig, './') === 0) {
+        if (str_starts_with($orig, './')) {
             $path = '/' . $path;
         }
-        if (strpos($orig, '../') === 0) {
+        if (str_starts_with($orig, '../')) {
             $path = '/' . $path;
         }
 
@@ -1112,7 +1113,7 @@ public function resolveRelativeURI(string $uri)
                     $transformed->setQuery($this->getQuery());
                 }
             } else {
-                if (strpos($relative->getPath(), '/') === 0) {
+                if (str_starts_with($relative->getPath(), '/')) {
                     $transformed->setPath($relative->getPath());
                 } else {
                     $transformed->setPath($this->mergePaths($this, $relative));
diff --git a/system/HTTP/UserAgent.php b/system/HTTP/UserAgent.php
index 77e7cb4392fc..4461ddc9db93 100644
--- a/system/HTTP/UserAgent.php
+++ b/system/HTTP/UserAgent.php
@@ -12,13 +12,14 @@
 namespace CodeIgniter\HTTP;
 
 use Config\UserAgents;
+use Stringable;
 
 /**
  * Abstraction for an HTTP user agent
  *
  * @see \CodeIgniter\HTTP\UserAgentTest
  */
-class UserAgent
+class UserAgent implements Stringable
 {
     /**
      * Current user-agent
diff --git a/system/Helpers/filesystem_helper.php b/system/Helpers/filesystem_helper.php
index 47c829bbc3c6..cd46d7dc3721 100644
--- a/system/Helpers/filesystem_helper.php
+++ b/system/Helpers/filesystem_helper.php
@@ -53,7 +53,7 @@ function directory_map(string $sourceDir, int $directoryDepth = 0, bool $hidden
             closedir($fp);
 
             return $fileData;
-        } catch (Throwable $e) {
+        } catch (Throwable) {
             return [];
         }
     }
@@ -129,7 +129,7 @@ function write_file(string $path, string $data, string $mode = 'wb'): bool
             fclose($fp);
 
             return is_int($result);
-        } catch (Throwable $e) {
+        } catch (Throwable) {
             return false;
         }
     }
@@ -178,7 +178,7 @@ function delete_files(string $path, bool $delDir = false, bool $htdocs = false,
             }
 
             return true;
-        } catch (Throwable $e) {
+        } catch (Throwable) {
             return false;
         }
     }
@@ -227,7 +227,7 @@ function get_filenames(
                     }
                 }
             }
-        } catch (Throwable $e) {
+        } catch (Throwable) {
             return [];
         }
 
@@ -277,7 +277,7 @@ function get_dir_file_info(string $sourceDir, bool $topLevelOnly = true, bool $r
             closedir($fp);
 
             return $fileData;
-        } catch (Throwable $fe) {
+        } catch (Throwable) {
             return [];
         }
     }
diff --git a/system/Helpers/form_helper.php b/system/Helpers/form_helper.php
index 7edb05cf1de3..8a86cf690a1e 100644
--- a/system/Helpers/form_helper.php
+++ b/system/Helpers/form_helper.php
@@ -32,9 +32,9 @@ function form_open(string $action = '', $attributes = [], array $hidden = []): s
         if (! $action) {
             $action = current_url(true);
         } // If an action is not a full URL then turn it into one
-        elseif (strpos($action, '://') === false) {
+        elseif (! str_contains($action, '://')) {
             // If an action has {locale}
-            if (strpos($action, '{locale}') !== false) {
+            if (str_contains($action, '{locale}')) {
                 $action = str_replace('{locale}', Services::request()->getLocale(), $action);
             }
 
@@ -61,7 +61,7 @@ function form_open(string $action = '', $attributes = [], array $hidden = []): s
         // Add CSRF field if enabled, but leave it out for GET requests and requests to external websites
         $before = Services::filters()->getFilters()['before'];
 
-        if ((in_array('csrf', $before, true) || array_key_exists('csrf', $before)) && strpos($action, base_url()) !== false && ! stripos($form, 'method="get"')) {
+        if ((in_array('csrf', $before, true) || array_key_exists('csrf', $before)) && str_contains($action, base_url()) && ! stripos($form, 'method="get"')) {
             $form .= csrf_field($csrfId ?? null);
         }
 
diff --git a/system/Helpers/html_helper.php b/system/Helpers/html_helper.php
index 7a76434d0ea2..e43bf0b2a7d2 100755
--- a/system/Helpers/html_helper.php
+++ b/system/Helpers/html_helper.php
@@ -108,7 +108,7 @@ function img($src = '', bool $indexPage = false, $attributes = ''): string
         $img = '<img';
 
         // Check for a relative URI
-        if (! preg_match('#^([a-z]+:)?//#i', $src['src']) && strpos($src['src'], 'data:') !== 0) {
+        if (! preg_match('#^([a-z]+:)?//#i', $src['src']) && ! str_starts_with($src['src'], 'data:')) {
             if ($indexPage === true) {
                 $img .= ' src="' . site_url($src['src']) . '"';
             } else {
diff --git a/system/Helpers/number_helper.php b/system/Helpers/number_helper.php
index 1b97d9a360db..b07cbbe1d4d6 100644
--- a/system/Helpers/number_helper.php
+++ b/system/Helpers/number_helper.php
@@ -25,7 +25,7 @@ function number_to_size($num, int $precision = 1, ?string $locale = null)
         try {
             // @phpstan-ignore-next-line
             $num = 0 + str_replace(',', '', (string) $num);
-        } catch (ErrorException $ee) {
+        } catch (ErrorException) {
             // Catch "Warning:  A non-numeric value encountered"
             return false;
         }
@@ -80,7 +80,7 @@ function number_to_amount($num, int $precision = 0, ?string $locale = null)
         try {
             // @phpstan-ignore-next-line
             $num = 0 + str_replace(',', '', $num);
-        } catch (ErrorException $ee) {
+        } catch (ErrorException) {
             return false;
         }
 
diff --git a/system/Helpers/text_helper.php b/system/Helpers/text_helper.php
index 48e013826a12..44f734ce6e9a 100755
--- a/system/Helpers/text_helper.php
+++ b/system/Helpers/text_helper.php
@@ -341,7 +341,7 @@ function word_wrap(string $str, int $charlim = 76): string
         $str = preg_replace('| +|', ' ', $str);
 
         // Standardize newlines
-        if (strpos($str, "\r") !== false) {
+        if (str_contains($str, "\r")) {
             $str = str_replace(["\r\n", "\r"], "\n", $str);
         }
 
diff --git a/system/Honeypot/Honeypot.php b/system/Honeypot/Honeypot.php
index 82da90020cac..7686d0bea695 100644
--- a/system/Honeypot/Honeypot.php
+++ b/system/Honeypot/Honeypot.php
@@ -44,7 +44,7 @@ public function __construct(HoneypotConfig $config)
             throw HoneypotException::forNoHiddenValue();
         }
 
-        if (empty($this->config->container) || strpos($this->config->container, '{template}') === false) {
+        if (empty($this->config->container) || ! str_contains($this->config->container, '{template}')) {
             $this->config->container = '<div style="display:none">{template}</div>';
         }
 
diff --git a/system/Images/Handlers/BaseHandler.php b/system/Images/Handlers/BaseHandler.php
index fef31755aaa3..10884805aae5 100644
--- a/system/Images/Handlers/BaseHandler.php
+++ b/system/Images/Handlers/BaseHandler.php
@@ -471,31 +471,16 @@ public function reorient(bool $silent = false)
     {
         $orientation = $this->getEXIF('Orientation', $silent);
 
-        switch ($orientation) {
-            case 2:
-                return $this->flip('horizontal');
-
-            case 3:
-                return $this->rotate(180);
-
-            case 4:
-                return $this->rotate(180)->flip('horizontal');
-
-            case 5:
-                return $this->rotate(270)->flip('horizontal');
-
-            case 6:
-                return $this->rotate(270);
-
-            case 7:
-                return $this->rotate(90)->flip('horizontal');
-
-            case 8:
-                return $this->rotate(90);
-
-            default:
-                return $this;
-        }
+        return match ($orientation) {
+            2       => $this->flip('horizontal'),
+            3       => $this->rotate(180),
+            4       => $this->rotate(180)->flip('horizontal'),
+            5       => $this->rotate(270)->flip('horizontal'),
+            6       => $this->rotate(270),
+            7       => $this->rotate(90)->flip('horizontal'),
+            8       => $this->rotate(90),
+            default => $this,
+        };
     }
 
     /**
diff --git a/system/Images/Handlers/ImageMagickHandler.php b/system/Images/Handlers/ImageMagickHandler.php
index 857a273d5372..839a2e4790cc 100644
--- a/system/Images/Handlers/ImageMagickHandler.php
+++ b/system/Images/Handlers/ImageMagickHandler.php
@@ -448,30 +448,15 @@ public function reorient(bool $silent = false)
     {
         $orientation = $this->getEXIF('Orientation', $silent);
 
-        switch ($orientation) {
-            case 2:
-                return $this->flip('horizontal');
-
-            case 3:
-                return $this->rotate(180);
-
-            case 4:
-                return $this->rotate(180)->flip('horizontal');
-
-            case 5:
-                return $this->rotate(90)->flip('horizontal');
-
-            case 6:
-                return $this->rotate(90);
-
-            case 7:
-                return $this->rotate(270)->flip('horizontal');
-
-            case 8:
-                return $this->rotate(270);
-
-            default:
-                return $this;
-        }
+        return match ($orientation) {
+            2       => $this->flip('horizontal'),
+            3       => $this->rotate(180),
+            4       => $this->rotate(180)->flip('horizontal'),
+            5       => $this->rotate(90)->flip('horizontal'),
+            6       => $this->rotate(90),
+            7       => $this->rotate(270)->flip('horizontal'),
+            8       => $this->rotate(270),
+            default => $this,
+        };
     }
 }
diff --git a/system/Language/Language.php b/system/Language/Language.php
index 8633f8a2dd9c..8c32a8214480 100644
--- a/system/Language/Language.php
+++ b/system/Language/Language.php
@@ -93,7 +93,7 @@ public function getLocale(): string
     public function getLine(string $line, array $args = [])
     {
         // if no file is given, just parse the line
-        if (strpos($line, '.') === false) {
+        if (! str_contains($line, '.')) {
             return $this->formatMessage($line, $args);
         }
 
diff --git a/system/Log/Handlers/ChromeLoggerHandler.php b/system/Log/Handlers/ChromeLoggerHandler.php
index b04d6f69238c..983ee274c6fc 100644
--- a/system/Log/Handlers/ChromeLoggerHandler.php
+++ b/system/Log/Handlers/ChromeLoggerHandler.php
@@ -142,7 +142,7 @@ protected function format($object)
         // @todo Modify formatting of objects once we can view them in browser.
         $objectArray = (array) $object;
 
-        $objectArray['___class_name'] = get_class($object);
+        $objectArray['___class_name'] = $object::class;
 
         return $objectArray;
     }
diff --git a/system/Log/Handlers/FileHandler.php b/system/Log/Handlers/FileHandler.php
index 88e384781a70..7c10d3231503 100644
--- a/system/Log/Handlers/FileHandler.php
+++ b/system/Log/Handlers/FileHandler.php
@@ -88,7 +88,7 @@ public function handle($level, $message): bool
         }
 
         // Instantiating DateTime with microseconds appended to initial date is needed for proper support of this format
-        if (strpos($this->dateFormat, 'u') !== false) {
+        if (str_contains($this->dateFormat, 'u')) {
             $microtimeFull  = microtime(true);
             $microtimeShort = sprintf('%06d', ($microtimeFull - floor($microtimeFull)) * 1_000_000);
             $date           = new DateTime(date('Y-m-d H:i:s.' . $microtimeShort, (int) $microtimeFull));
diff --git a/system/Log/Logger.php b/system/Log/Logger.php
index 2c17ded5f7c9..f23b06cc3be9 100644
--- a/system/Log/Logger.php
+++ b/system/Log/Logger.php
@@ -339,7 +339,7 @@ protected function interpolate($message, array $context = [])
         $replace['{env}']       = ENVIRONMENT;
 
         // Allow us to log the file/line that we are logging from
-        if (strpos($message, '{file}') !== false) {
+        if (str_contains($message, '{file}')) {
             [$file, $line] = $this->determineFile();
 
             $replace['{file}'] = $file;
@@ -347,7 +347,7 @@ protected function interpolate($message, array $context = [])
         }
 
         // Match up environment variables in {env:foo} tags.
-        if (strpos($message, 'env:') !== false) {
+        if (str_contains($message, 'env:')) {
             preg_match('/env:[^}]+/', $message, $matches);
 
             foreach ($matches as $str) {
diff --git a/system/Model.php b/system/Model.php
index b64c8225e17c..84601fb0f074 100644
--- a/system/Model.php
+++ b/system/Model.php
@@ -504,7 +504,7 @@ protected function doErrors()
             return [];
         }
 
-        return [get_class($this->db) => $error['message']];
+        return [$this->db::class => $error['message']];
     }
 
     /**
diff --git a/system/Pager/Pager.php b/system/Pager/Pager.php
index b08cb00410fd..73d45d6a728d 100644
--- a/system/Pager/Pager.php
+++ b/system/Pager/Pager.php
@@ -425,7 +425,7 @@ protected function calculateCurrentPage(string $group)
             try {
                 $this->groups[$group]['currentPage'] = (int) $this->groups[$group]['currentUri']
                     ->setSilent(false)->getSegment($this->segment[$group]);
-            } catch (HTTPException $e) {
+            } catch (HTTPException) {
                 $this->groups[$group]['currentPage'] = 1;
             }
         } else {
diff --git a/system/Publisher/Publisher.php b/system/Publisher/Publisher.php
index 589e88381ebe..725c15368354 100644
--- a/system/Publisher/Publisher.php
+++ b/system/Publisher/Publisher.php
@@ -167,7 +167,7 @@ public function __construct(?string $source = null, ?string $destination = null)
 
         // Make sure the destination is allowed
         foreach (array_keys($this->restrictions) as $directory) {
-            if (strpos($this->destination, $directory) === 0) {
+            if (str_starts_with($this->destination, $directory)) {
                 return;
             }
         }
@@ -470,7 +470,7 @@ private function verifyAllowed(string $from, string $to): void
     {
         // Verify this is an allowed file for its destination
         foreach ($this->restrictions as $directory => $pattern) {
-            if (strpos($to, $directory) === 0 && self::matchFiles([$to], $pattern) === []) {
+            if (str_starts_with($to, $directory) && self::matchFiles([$to], $pattern) === []) {
                 throw PublisherException::forFileNotAllowed($from, $directory, $pattern);
             }
         }
diff --git a/system/RESTful/BaseResource.php b/system/RESTful/BaseResource.php
index 1c21f65da860..269014ee8b77 100644
--- a/system/RESTful/BaseResource.php
+++ b/system/RESTful/BaseResource.php
@@ -69,7 +69,7 @@ public function setModel($which = null)
         }
 
         if (! empty($this->model) && empty($this->modelName)) {
-            $this->modelName = get_class($this->model);
+            $this->modelName = $this->model::class;
         }
     }
 }
diff --git a/system/Router/AutoRouter.php b/system/Router/AutoRouter.php
index 281b8a49732a..ec4622a15867 100644
--- a/system/Router/AutoRouter.php
+++ b/system/Router/AutoRouter.php
@@ -134,13 +134,13 @@ public function getRoute(string $uri, string $httpVerb): array
                     $handler = strtolower($handler);
 
                     // Like $routes->cli('hello/(:segment)', 'Home::$1')
-                    if (strpos($handler, '::$') !== false) {
+                    if (str_contains($handler, '::$')) {
                         throw new PageNotFoundException(
                             'Cannot access CLI Route: ' . $uri
                         );
                     }
 
-                    if (strpos($handler, $controller . '::' . $methodName) === 0) {
+                    if (str_starts_with($handler, $controller . '::' . $methodName)) {
                         throw new PageNotFoundException(
                             'Cannot access CLI Route: ' . $uri
                         );
@@ -166,7 +166,7 @@ public function getRoute(string $uri, string $httpVerb): array
 
         // Ensure the controller stores the fully-qualified class name
         // We have to check for a length over 1, since by default it will be '\'
-        if (strpos($this->controller, '\\') === false && strlen($this->defaultNamespace) > 1) {
+        if (! str_contains($this->controller, '\\') && strlen($this->defaultNamespace) > 1) {
             $this->controller = '\\' . ltrim(
                 str_replace(
                     '/',
diff --git a/system/Router/AutoRouterImproved.php b/system/Router/AutoRouterImproved.php
index a86e92f0161a..6d26cf38f4f1 100644
--- a/system/Router/AutoRouterImproved.php
+++ b/system/Router/AutoRouterImproved.php
@@ -344,7 +344,7 @@ public function getRoute(string $uri, string $httpVerb): array
         // Check parameter count
         try {
             $this->checkParameters($uri);
-        } catch (MethodNotFoundException $e) {
+        } catch (MethodNotFoundException) {
             throw PageNotFoundException::forControllerNotFound($this->controller, $this->method);
         }
 
@@ -411,14 +411,14 @@ private function checkParameters(string $uri): void
     {
         try {
             $refClass = new ReflectionClass($this->controller);
-        } catch (ReflectionException $e) {
+        } catch (ReflectionException) {
             throw PageNotFoundException::forControllerNotFound($this->controller, $this->method);
         }
 
         try {
             $refMethod = $refClass->getMethod($this->method);
             $refParams = $refMethod->getParameters();
-        } catch (ReflectionException $e) {
+        } catch (ReflectionException) {
             throw new MethodNotFoundException();
         }
 
@@ -445,7 +445,7 @@ private function checkRemap(): void
                 'AutoRouterImproved does not support `_remap()` method.'
                 . ' Controller:' . $this->controller
             );
-        } catch (ReflectionException $e) {
+        } catch (ReflectionException) {
             // Do nothing.
         }
     }
@@ -459,7 +459,7 @@ private function checkUnderscore(string $uri): void
         $paramPos = $this->paramPos ?? count($this->segments);
 
         for ($i = 0; $i < $paramPos; $i++) {
-            if (strpos($this->segments[$i], '_') !== false) {
+            if (str_contains($this->segments[$i], '_')) {
                 throw new PageNotFoundException(
                     'AutoRouterImproved prohibits access to the URI'
                     . ' containing underscores ("' . $this->segments[$i] . '")'
diff --git a/system/Router/RouteCollection.php b/system/Router/RouteCollection.php
index 47ac4b63b62e..ea434001cb46 100644
--- a/system/Router/RouteCollection.php
+++ b/system/Router/RouteCollection.php
@@ -1205,8 +1205,8 @@ public function reverseRoute(string $search, ...$params)
         // Add the default namespace if needed.
         $namespace = trim($this->defaultNamespace, '\\') . '\\';
         if (
-            substr($search, 0, 1) !== '\\'
-            && substr($search, 0, strlen($namespace)) !== $namespace
+            ! str_starts_with($search, '\\')
+            && ! str_starts_with($search, $namespace)
         ) {
             $search = $namespace . $search;
         }
@@ -1230,7 +1230,7 @@ public function reverseRoute(string $search, ...$params)
 
                 // If there's any chance of a match, then it will
                 // be with $search at the beginning of the $to string.
-                if (strpos($to, $search) !== 0) {
+                if (! str_starts_with($to, $search)) {
                     continue;
                 }
 
@@ -1352,7 +1352,7 @@ protected function buildReverseRoute(string $from, array $params): string
         preg_match_all('/\(([^)]+)\)/', $from, $matches);
 
         if (empty($matches[0])) {
-            if (strpos($from, '{locale}') !== false) {
+            if (str_contains($from, '{locale}')) {
                 $locale = $params[0] ?? null;
             }
 
@@ -1407,7 +1407,7 @@ protected function buildReverseRoute(string $from, array $params): string
      */
     private function replaceLocale(string $route, ?string $locale = null): string
     {
-        if (strpos($route, '{locale}') === false) {
+        if (! str_contains($route, '{locale}')) {
             return $route;
         }
 
@@ -1512,7 +1512,7 @@ protected function create(string $verb, string $from, $to, ?array $options = nul
         // If is redirect, No processing
         if (! isset($options['redirect']) && is_string($to)) {
             // If no namespace found, add the default namespace
-            if (strpos($to, '\\') === false || strpos($to, '\\') > 0) {
+            if (! str_contains($to, '\\') || strpos($to, '\\') > 0) {
                 $namespace = $options['namespace'] ?? $this->defaultNamespace;
                 $to        = trim($namespace, '\\') . '\\' . $to;
             }
@@ -1651,7 +1651,7 @@ private function determineCurrentSubdomain()
         // on the URL else parse_url will mis-interpret
         // 'host' as the 'path'.
         $url = $this->httpHost;
-        if (strpos($url, 'http') !== 0) {
+        if (! str_starts_with($url, 'http')) {
             $url = 'http://' . $url;
         }
 
diff --git a/system/Router/Router.php b/system/Router/Router.php
index e00031feb2d8..e7b0c087c07d 100644
--- a/system/Router/Router.php
+++ b/system/Router/Router.php
@@ -406,7 +406,7 @@ protected function checkRoutes(string $uri): bool
             $matchedKey = $routeKey;
 
             // Are we dealing with a locale?
-            if (strpos($routeKey, '{locale}') !== false) {
+            if (str_contains($routeKey, '{locale}')) {
                 $routeKey = str_replace('{locale}', '[^/]+', $routeKey);
             }
 
@@ -428,7 +428,7 @@ protected function checkRoutes(string $uri): bool
                 }
                 // Store our locale so CodeIgniter object can
                 // assign it to the Request.
-                if (strpos($matchedKey, '{locale}') !== false) {
+                if (str_contains($matchedKey, '{locale}')) {
                     preg_match(
                         '#^' . str_replace('{locale}', '(?<locale>[^/]+)', $matchedKey) . '$#u',
                         $uri,
@@ -465,13 +465,13 @@ protected function checkRoutes(string $uri): bool
                 [$controller] = explode('::', $handler);
 
                 // Checks `/` in controller name
-                if (strpos($controller, '/') !== false) {
+                if (str_contains($controller, '/')) {
                     throw RouterException::forInvalidControllerName($handler);
                 }
 
-                if (strpos($handler, '$') !== false && strpos($routeKey, '(') !== false) {
+                if (str_contains($handler, '$') && str_contains($routeKey, '(')) {
                     // Checks dynamic controller
-                    if (strpos($controller, '$') !== false) {
+                    if (str_contains($controller, '$')) {
                         throw RouterException::forDynamicController($handler);
                     }
 
diff --git a/system/Security/Security.php b/system/Security/Security.php
index 9c28b82335b0..167f864e2bea 100644
--- a/system/Security/Security.php
+++ b/system/Security/Security.php
@@ -292,7 +292,7 @@ public function verify(RequestInterface $request)
         try {
             $token = ($postedToken !== null && $this->config->tokenRandomize)
                 ? $this->derandomize($postedToken) : $postedToken;
-        } catch (InvalidArgumentException $e) {
+        } catch (InvalidArgumentException) {
             $token = null;
         }
 
diff --git a/system/Test/CIUnitTestCase.php b/system/Test/CIUnitTestCase.php
index 266a22b0161d..40a4da68153e 100644
--- a/system/Test/CIUnitTestCase.php
+++ b/system/Test/CIUnitTestCase.php
@@ -477,7 +477,7 @@ public function assertCloseEnoughString($expected, $actual, string $message = ''
             $difference = abs($expected - $actual);
 
             $this->assertLessThanOrEqual($tolerance, $difference, $message);
-        } catch (Exception $e) {
+        } catch (Exception) {
             return false;
         }
     }
@@ -515,7 +515,7 @@ protected function getHeaderEmitted(string $header, bool $ignoreCase = false, st
         foreach (xdebug_get_headers() as $emittedHeader) {
             $found = $ignoreCase
                 ? (stripos($emittedHeader, $header) === 0)
-                : (strpos($emittedHeader, $header) === 0);
+                : (str_starts_with($emittedHeader, $header));
 
             if ($found) {
                 return $emittedHeader;
diff --git a/system/Test/ControllerTestTrait.php b/system/Test/ControllerTestTrait.php
index a99b899eaf63..25a8416d17d6 100644
--- a/system/Test/ControllerTestTrait.php
+++ b/system/Test/ControllerTestTrait.php
@@ -202,7 +202,7 @@ public function execute(string $method, ...$params)
             // getStatusCode() throws for empty codes
             try {
                 $response->getStatusCode();
-            } catch (HTTPException $e) {
+            } catch (HTTPException) {
                 // If no code has been set then assume success
                 $response->setStatusCode(200);
             }
diff --git a/system/Test/DOMParser.php b/system/Test/DOMParser.php
index 1a2cbb0d61aa..4cc56071670a 100644
--- a/system/Test/DOMParser.php
+++ b/system/Test/DOMParser.php
@@ -258,11 +258,11 @@ public function parseSelector(string $selector)
         $attr  = null;
 
         // ID?
-        if (strpos($selector, '#') !== false) {
+        if (str_contains($selector, '#')) {
             [$tag, $id] = explode('#', $selector);
         }
         // Attribute
-        elseif (strpos($selector, '[') !== false && strpos($selector, ']') !== false) {
+        elseif (str_contains($selector, '[') && str_contains($selector, ']')) {
             $open  = strpos($selector, '[');
             $close = strpos($selector, ']');
 
@@ -280,7 +280,7 @@ public function parseSelector(string $selector)
             $attr  = [$name => trim($value, '] ')];
         }
         // Class?
-        elseif (strpos($selector, '.') !== false) {
+        elseif (str_contains($selector, '.')) {
             [$tag, $class] = explode('.', $selector);
         }
         // Otherwise, assume the entire string is our tag
diff --git a/system/Test/DatabaseTestTrait.php b/system/Test/DatabaseTestTrait.php
index d7b8b02ddaa8..247cc74ee564 100644
--- a/system/Test/DatabaseTestTrait.php
+++ b/system/Test/DatabaseTestTrait.php
@@ -239,7 +239,7 @@ protected function clearInsertCache()
      */
     public function loadBuilder(string $tableName)
     {
-        $builderClass = str_replace('Connection', 'Builder', get_class($this->db));
+        $builderClass = str_replace('Connection', 'Builder', $this->db::class);
 
         return new $builderClass($tableName, $this->db);
     }
diff --git a/system/Test/Fabricator.php b/system/Test/Fabricator.php
index 3a28f281d127..66a685fc8d30 100644
--- a/system/Test/Fabricator.php
+++ b/system/Test/Fabricator.php
@@ -305,7 +305,7 @@ protected function guessFormatter($field): string
             $this->faker->getFormatter($field);
 
             return $field;
-        } catch (InvalidArgumentException $e) {
+        } catch (InvalidArgumentException) {
             // No match, keep going
         }
 
@@ -497,18 +497,11 @@ public function create(?int $count = null, bool $mock = false)
      */
     protected function createMock(?int $count = null)
     {
-        switch ($this->model->dateFormat) {
-            case 'datetime':
-                $datetime = date('Y-m-d H:i:s');
-                break;
-
-            case 'date':
-                $datetime = date('Y-m-d');
-                break;
-
-            default:
-                $datetime = Time::now()->getTimestamp();
-        }
+        $datetime = match ($this->model->dateFormat) {
+            'datetime' => date('Y-m-d H:i:s'),
+            'date'     => date('Y-m-d'),
+            default    => Time::now()->getTimestamp(),
+        };
 
         // Determine which fields we will need
         $fields = [];
diff --git a/system/Test/FilterTestTrait.php b/system/Test/FilterTestTrait.php
index 523717e54679..14bf81db9271 100644
--- a/system/Test/FilterTestTrait.php
+++ b/system/Test/FilterTestTrait.php
@@ -131,7 +131,7 @@ protected function getFilterCaller($filter, string $position): Closure
 
         if (is_string($filter)) {
             // Check for an alias (no namespace)
-            if (strpos($filter, '\\') === false) {
+            if (! str_contains($filter, '\\')) {
                 if (! isset($this->filtersConfig->aliases[$filter])) {
                     throw new RuntimeException("No filter found with alias '{$filter}'");
                 }
@@ -149,7 +149,7 @@ protected function getFilterCaller($filter, string $position): Closure
                 $filter = new $class();
 
                 if (! $filter instanceof FilterInterface) {
-                    throw FilterException::forIncorrectInterface(get_class($filter));
+                    throw FilterException::forIncorrectInterface($filter::class);
                 }
 
                 $filterInstances[] = $filter;
diff --git a/system/Test/TestLogger.php b/system/Test/TestLogger.php
index dce1277d98d2..3f453ca5cb0d 100644
--- a/system/Test/TestLogger.php
+++ b/system/Test/TestLogger.php
@@ -80,7 +80,7 @@ public static function didLog(string $level, $message, bool $useExactComparison
                 continue;
             }
 
-            if (strpos($log['message'], $message) !== false) {
+            if (str_contains($log['message'], $message)) {
                 return true;
             }
         }
diff --git a/system/Typography/Typography.php b/system/Typography/Typography.php
index fd763cd52e86..1442c2f6e51a 100644
--- a/system/Typography/Typography.php
+++ b/system/Typography/Typography.php
@@ -82,7 +82,7 @@ public function autoTypography(string $str, bool $reduceLinebreaks = false): str
         }
 
         // Standardize Newlines to make matching easier
-        if (strpos($str, "\r") !== false) {
+        if (str_contains($str, "\r")) {
             $str = str_replace(["\r\n", "\r"], "\n", $str);
         }
 
@@ -94,7 +94,7 @@ public function autoTypography(string $str, bool $reduceLinebreaks = false): str
 
         // HTML comment tags don't conform to patterns of normal tags, so pull them out separately, only if needed
         $htmlComments = [];
-        if (strpos($str, '<!--') !== false && preg_match_all('#(<!\-\-.*?\-\->)#s', $str, $matches)) {
+        if (str_contains($str, '<!--') && preg_match_all('#(<!\-\-.*?\-\->)#s', $str, $matches)) {
             for ($i = 0, $total = count($matches[0]); $i < $total; $i++) {
                 $htmlComments[] = $matches[0][$i];
                 $str            = str_replace($matches[0][$i], '{@HC' . $i . '}', $str);
@@ -103,7 +103,7 @@ public function autoTypography(string $str, bool $reduceLinebreaks = false): str
 
         // match and yank <pre> tags if they exist.  It's cheaper to do this separately since most content will
         // not contain <pre> tags, and it keeps the PCRE patterns below simpler and faster
-        if (strpos($str, '<pre') !== false) {
+        if (str_contains($str, '<pre')) {
             $str = preg_replace_callback('#<pre.*?>.*?</pre>#si', [$this, 'protectCharacters'], $str);
         }
 
@@ -283,7 +283,7 @@ public function formatCharacters(string $str): string
      */
     protected function formatNewLines(string $str): string
     {
-        if ($str === '' || (strpos($str, "\n") === false && ! in_array($this->lastBlockElement, $this->innerBlockRequired, true))) {
+        if ($str === '' || (! str_contains($str, "\n") && ! in_array($this->lastBlockElement, $this->innerBlockRequired, true))) {
             return $str;
         }
 
diff --git a/system/Validation/CreditCardRules.php b/system/Validation/CreditCardRules.php
index 61f59d7bfe86..e490b004e33b 100644
--- a/system/Validation/CreditCardRules.php
+++ b/system/Validation/CreditCardRules.php
@@ -215,7 +215,7 @@ public function valid_cc_number(?string $ccNumber, string $type): bool
         $validPrefix = false;
 
         foreach ($prefixes as $prefix) {
-            if (strpos($ccNumber, $prefix) === 0) {
+            if (str_starts_with($ccNumber, $prefix)) {
                 $validPrefix = true;
                 break;
             }
diff --git a/system/Validation/FormatRules.php b/system/Validation/FormatRules.php
index 8a16c98e4a33..592f206c9cf6 100644
--- a/system/Validation/FormatRules.php
+++ b/system/Validation/FormatRules.php
@@ -240,7 +240,7 @@ public function regex_match($str, string $pattern): bool
             $str = (string) $str;
         }
 
-        if (strpos($pattern, '/') !== 0) {
+        if (! str_starts_with($pattern, '/')) {
             $pattern = "/{$pattern}/";
         }
 
@@ -365,18 +365,11 @@ public function valid_ip($ip = null, ?string $which = null): bool
             return false;
         }
 
-        switch (strtolower($which ?? '')) {
-            case 'ipv4':
-                $option = FILTER_FLAG_IPV4;
-                break;
-
-            case 'ipv6':
-                $option = FILTER_FLAG_IPV6;
-                break;
-
-            default:
-                $option = 0;
-        }
+        $option = match (strtolower($which ?? '')) {
+            'ipv4'  => FILTER_FLAG_IPV4,
+            'ipv6'  => FILTER_FLAG_IPV6,
+            default => 0,
+        };
 
         return filter_var($ip, FILTER_VALIDATE_IP, $option) !== false
             || (! ctype_print($ip) && filter_var(inet_ntop($ip), FILTER_VALIDATE_IP, $option) !== false);
diff --git a/system/Validation/Rules.php b/system/Validation/Rules.php
index 0af5be8166f0..00a4480676f4 100644
--- a/system/Validation/Rules.php
+++ b/system/Validation/Rules.php
@@ -30,7 +30,7 @@ class Rules
      */
     public function differs($str, string $field, array $data): bool
     {
-        if (strpos($field, '.') !== false) {
+        if (str_contains($field, '.')) {
             return $str !== dot_array_search($field, $data);
         }
 
@@ -238,7 +238,7 @@ public function less_than_equal_to($str, string $max): bool
      */
     public function matches($str, string $field, array $data): bool
     {
-        if (strpos($field, '.') !== false) {
+        if (str_contains($field, '.')) {
             return $str === dot_array_search($field, $data);
         }
 
@@ -356,7 +356,7 @@ public function required_with($str = null, ?string $fields = null, array $data =
         foreach (explode(',', $fields) as $field) {
             if (
                 (array_key_exists($field, $data) && ! empty($data[$field]))
-                || (strpos($field, '.') !== false && ! empty(dot_array_search($field, $data)))
+                || (str_contains($field, '.') && ! empty(dot_array_search($field, $data)))
             ) {
                 $requiredFields[] = $field;
             }
@@ -401,13 +401,13 @@ public function required_without(
         // any of the fields are not present in $data
         foreach (explode(',', $otherFields) as $otherField) {
             if (
-                (strpos($otherField, '.') === false)
+                (! str_contains($otherField, '.'))
                 && (! array_key_exists($otherField, $data) || empty($data[$otherField]))
             ) {
                 return false;
             }
 
-            if (strpos($otherField, '.') !== false) {
+            if (str_contains($otherField, '.')) {
                 if ($field === null) {
                     throw new InvalidArgumentException('You must supply the parameters: field.');
                 }
diff --git a/system/Validation/Validation.php b/system/Validation/Validation.php
index ec835c5212fd..82d0e8d4a6d6 100644
--- a/system/Validation/Validation.php
+++ b/system/Validation/Validation.php
@@ -168,7 +168,7 @@ public function run(?array $data = null, ?string $group = null, ?string $dbGroup
                 $rules = $this->splitRules($rules);
             }
 
-            if (strpos($field, '*') !== false) {
+            if (str_contains($field, '*')) {
                 $flattenedArray = array_flatten_with_dots($data);
 
                 $values = array_filter(
@@ -190,7 +190,7 @@ public function run(?array $data = null, ?string $group = null, ?string $dbGroup
                 continue;
             }
 
-            if (strpos($field, '*') !== false) {
+            if (str_contains($field, '*')) {
                 // Process multiple fields
                 foreach ($values as $dotField => $value) {
                     $this->processRules($dotField, $setup['label'] ?? $field, $value, $rules, $data, $field);
@@ -386,7 +386,7 @@ private function processIfExist(string $field, array $rules, array $data)
             $flattenedData = array_flatten_with_dots($data);
             $ifExistField  = $field;
 
-            if (strpos($field, '.*') !== false) {
+            if (str_contains($field, '.*')) {
                 // We'll change the dot notation into a PCRE pattern that can be used later
                 $ifExistField   = str_replace('\.\*', '\.(?:[^\.]+)', preg_quote($field, '/'));
                 $dataIsExisting = false;
@@ -502,14 +502,14 @@ private function isStringList(array $array): bool
     public function withRequest(RequestInterface $request): ValidationInterface
     {
         /** @var IncomingRequest $request */
-        if (strpos($request->getHeaderLine('Content-Type'), 'application/json') !== false) {
+        if (str_contains($request->getHeaderLine('Content-Type'), 'application/json')) {
             $this->data = $request->getJSON(true);
 
             return $this;
         }
 
         if (in_array($request->getMethod(), [Method::PUT, Method::PATCH, Method::DELETE], true)
-            && strpos($request->getHeaderLine('Content-Type'), 'multipart/form-data') === false
+            && ! str_contains($request->getHeaderLine('Content-Type'), 'multipart/form-data')
         ) {
             $this->data = $request->getRawInput();
         } else {
@@ -931,7 +931,7 @@ protected function getErrorMessage(
      */
     protected function splitRules(string $rules): array
     {
-        if (strpos($rules, '|') === false) {
+        if (! str_contains($rules, '|')) {
             return [$rules];
         }
 
diff --git a/system/View/Cell.php b/system/View/Cell.php
index c5df775664ba..5ff1603179f1 100644
--- a/system/View/Cell.php
+++ b/system/View/Cell.php
@@ -78,7 +78,7 @@ public function render(string $library, $params = null, int $ttl = 0, ?string $c
         [$instance, $method] = $this->determineClass($library);
 
         $class = is_object($instance)
-            ? get_class($instance)
+            ? $instance::class
             : null;
 
         $params = $this->prepareParams($params);
@@ -132,7 +132,7 @@ public function prepareParams($params)
             $newParams = [];
             $separator = ' ';
 
-            if (strpos($params, ',') !== false) {
+            if (str_contains($params, ',')) {
                 $separator = ',';
             }
 
@@ -170,7 +170,7 @@ protected function determineClass(string $library): array
 
         // controlled cells might be called with just
         // the class name, so add a default method
-        if (strpos($library, ':') === false) {
+        if (! str_contains($library, ':')) {
             $library .= ':render';
         }
 
@@ -252,7 +252,7 @@ private function getMethodParams(BaseCell $instance, string $method, array $para
                     $mountParams[] = $params[$paramName];
                 }
             }
-        } catch (ReflectionException $e) {
+        } catch (ReflectionException) {
             // do nothing
         }
 
diff --git a/system/View/Cells/Cell.php b/system/View/Cells/Cell.php
index 328bae1f8953..b8c43e173b45 100644
--- a/system/View/Cells/Cell.php
+++ b/system/View/Cells/Cell.php
@@ -14,6 +14,7 @@
 use CodeIgniter\Traits\PropertiesTrait;
 use LogicException;
 use ReflectionClass;
+use Stringable;
 
 /**
  * Class Cell
@@ -24,7 +25,7 @@
  *
  * @function mount()
  */
-class Cell
+class Cell implements Stringable
 {
     use PropertiesTrait;
 
diff --git a/system/View/Filters.php b/system/View/Filters.php
index 379ccac186bb..4a686a1dea9d 100644
--- a/system/View/Filters.php
+++ b/system/View/Filters.php
@@ -229,19 +229,12 @@ public static function round(string $value, $precision = 2, string $type = 'comm
             $precision = (int) $precision;
         }
 
-        switch ($type) {
-            case 'common':
-                return round((float) $value, $precision);
-
-            case 'ceil':
-                return ceil((float) $value);
-
-            case 'floor':
-                return floor((float) $value);
-        }
-
-        // Still here, just return the value.
-        return $value;
+        return match ($type) {
+            'common' => round((float) $value, $precision),
+            'ceil'   => ceil((float) $value),
+            'floor'  => floor((float) $value),
+            default  => $value,
+        };
     }
 
     /**
diff --git a/system/View/Parser.php b/system/View/Parser.php
index 62b63a1eaaa8..64a767c1b0cf 100644
--- a/system/View/Parser.php
+++ b/system/View/Parser.php
@@ -337,7 +337,7 @@ protected function parsePair(string $variable, array $data, string $template): a
                     }
 
                     if (is_object($val)) {
-                        $val = 'Class: ' . get_class($val);
+                        $val = 'Class: ' . $val::class;
                     } elseif (is_resource($val)) {
                         $val = 'Resource';
                     }
@@ -467,7 +467,7 @@ protected function parseConditionals(string $template): string
 
         try {
             eval('?>' . $template . '<?php ');
-        } catch (ParseError $e) {
+        } catch (ParseError) {
             ob_end_clean();
 
             throw ViewException::forTagSyntaxError(str_replace(['?>', '<?php '], '', $template));
@@ -520,7 +520,7 @@ protected function replaceSingle($pattern, $content, $template, bool $escape = f
         return preg_replace_callback($pattern, function ($matches) use ($content, $escape) {
             // Check for {! !} syntax to not escape this one.
             if (
-                strpos($matches[0], $this->leftDelimiter . '!') === 0
+                str_starts_with($matches[0], $this->leftDelimiter . '!')
                 && substr($matches[0], -1 - strlen($this->rightDelimiter)) === '!' . $this->rightDelimiter
             ) {
                 $escape = false;
@@ -567,11 +567,11 @@ public function shouldAddEscaping(string $key)
             }
         }
         // No pipes, then we know we need to escape
-        elseif (strpos($key, '|') === false) {
+        elseif (! str_contains($key, '|')) {
             $escape = 'html';
         }
         // If there's a `noescape` then we're definitely false.
-        elseif (strpos($key, 'noescape') !== false) {
+        elseif (str_contains($key, 'noescape')) {
             $escape = false;
         }
         // If no `esc` filter is found, then we'll need to add one.
diff --git a/tests/system/AutoReview/ComposerJsonTest.php b/tests/system/AutoReview/ComposerJsonTest.php
index ecc57c028cba..ae8c5987bce6 100644
--- a/tests/system/AutoReview/ComposerJsonTest.php
+++ b/tests/system/AutoReview/ComposerJsonTest.php
@@ -92,18 +92,11 @@ public function testStarterConfigIsTheSameWithDevSuggest(): void
 
     private function checkSection(string $section, string $component): void
     {
-        switch (strtolower($component)) {
-            case 'framework':
-                $sectionContent = $this->frameworkComposer[$section] ?? null;
-                break;
-
-            case 'starter':
-                $sectionContent = $this->starterComposer[$section] ?? null;
-                break;
-
-            default:
-                throw new InvalidArgumentException(sprintf('Unknown component: %s.', $component));
-        }
+        $sectionContent = match (strtolower($component)) {
+            'framework' => $this->frameworkComposer[$section] ?? null,
+            'starter'   => $this->starterComposer[$section] ?? null,
+            default     => throw new InvalidArgumentException(sprintf('Unknown component: %s.', $component)),
+        };
 
         $this->assertSame(
             $this->devComposer[$section],
diff --git a/tests/system/AutoReview/FrameworkCodeTest.php b/tests/system/AutoReview/FrameworkCodeTest.php
index 6583c9f2839e..4fc85d0c5061 100644
--- a/tests/system/AutoReview/FrameworkCodeTest.php
+++ b/tests/system/AutoReview/FrameworkCodeTest.php
@@ -122,8 +122,8 @@ static function (SplFileInfo $file) use ($directory): string {
             array_filter(
                 iterator_to_array($iterator, false),
                 static fn (SplFileInfo $file): bool => $file->isFile()
-                    && strpos($file->getPathname(), DIRECTORY_SEPARATOR . 'fixtures' . DIRECTORY_SEPARATOR) === false
-                    && strpos($file->getPathname(), DIRECTORY_SEPARATOR . 'Views' . DIRECTORY_SEPARATOR) === false
+                    && ! str_contains($file->getPathname(), DIRECTORY_SEPARATOR . 'fixtures' . DIRECTORY_SEPARATOR)
+                    && ! str_contains($file->getPathname(), DIRECTORY_SEPARATOR . 'Views' . DIRECTORY_SEPARATOR)
             )
         );
 
diff --git a/tests/system/Commands/CommandGeneratorTest.php b/tests/system/Commands/CommandGeneratorTest.php
index aabb86f9a843..f70929887e31 100644
--- a/tests/system/Commands/CommandGeneratorTest.php
+++ b/tests/system/Commands/CommandGeneratorTest.php
@@ -32,7 +32,7 @@ protected function tearDown(): void
         if (is_file($file)) {
             unlink($file);
         }
-        if (is_dir($dir) && strpos($dir, 'Commands') !== false) {
+        if (is_dir($dir) && str_contains($dir, 'Commands')) {
             rmdir($dir);
         }
     }
diff --git a/tests/system/CommonFunctionsTest.php b/tests/system/CommonFunctionsTest.php
index ac5e70796bb8..1b557036c1e6 100644
--- a/tests/system/CommonFunctionsTest.php
+++ b/tests/system/CommonFunctionsTest.php
@@ -772,7 +772,7 @@ public function testLangOnCLI(): void
 
     public function testIsWindows(): void
     {
-        $this->assertSame(strpos(php_uname(), 'Windows') !== false, is_windows());
+        $this->assertSame(str_contains(php_uname(), 'Windows'), is_windows());
         $this->assertSame(defined('PHP_WINDOWS_VERSION_MAJOR'), is_windows());
     }
 
@@ -787,7 +787,7 @@ public function testIsWindowsUsingMock(): void
         $this->assertNotTrue(is_windows());
 
         is_windows(null);
-        $this->assertSame(strpos(php_uname(), 'Windows') !== false, is_windows());
+        $this->assertSame(str_contains(php_uname(), 'Windows'), is_windows());
         $this->assertSame(defined('PHP_WINDOWS_VERSION_MAJOR'), is_windows());
     }
 }
diff --git a/tests/system/CommonHelperTest.php b/tests/system/CommonHelperTest.php
index 46603dee30ad..e9473e001127 100644
--- a/tests/system/CommonHelperTest.php
+++ b/tests/system/CommonHelperTest.php
@@ -94,7 +94,7 @@ public function testHelperWithFatalLocatorThrowsException(): void
         try {
             helper('baguette');
             $exception = false;
-        } catch (RuntimeException $e) {
+        } catch (RuntimeException) {
             $exception = true;
         }
 
@@ -113,7 +113,7 @@ public function testHelperLoadsOnce(): void
         try {
             helper('baguette');
             $exception = false;
-        } catch (RuntimeException $e) {
+        } catch (RuntimeException) {
             $exception = true;
         }
 
diff --git a/tests/system/CommonSingleServiceTest.php b/tests/system/CommonSingleServiceTest.php
index e95e4c493136..9d5c65f49224 100644
--- a/tests/system/CommonSingleServiceTest.php
+++ b/tests/system/CommonSingleServiceTest.php
@@ -38,7 +38,7 @@ public function testSingleServiceWithNoParamsSupplied(string $service): void
 
         assert($service1 !== null);
 
-        $this->assertInstanceOf(get_class($service1), $service2);
+        $this->assertInstanceOf($service1::class, $service2);
         $this->assertNotSame($service1, $service2);
     }
 
@@ -68,7 +68,7 @@ public function testSingleServiceWithAtLeastOneParamSupplied(string $service): v
 
         assert($service1 !== null);
 
-        $this->assertInstanceOf(get_class($service1), $service2);
+        $this->assertInstanceOf($service1::class, $service2);
         $this->assertNotSame($service1, $service2);
 
         if ($service === 'commands') {
@@ -86,7 +86,7 @@ public function testSingleServiceWithAllParamsSupplied(): void
 
         // Assert that even passing true as last param this will
         // not create a shared instance.
-        $this->assertInstanceOf(get_class($cache1), $cache2);
+        $this->assertInstanceOf($cache1::class, $cache2);
         $this->assertNotSame($cache1, $cache2);
     }
 
diff --git a/tests/system/ControllerTest.php b/tests/system/ControllerTest.php
index 14756039c161..567a1aada6dc 100644
--- a/tests/system/ControllerTest.php
+++ b/tests/system/ControllerTest.php
@@ -82,7 +82,7 @@ public function testConstructorHTTPS(): void
                 protected $forceHTTPS = 1;
             };
             $this->controller->initController($this->request, $this->response, $this->logger);
-        } catch (RedirectException $e) {
+        } catch (RedirectException) {
         }
 
         $this->assertInstanceOf(Controller::class, $this->controller);
diff --git a/tests/system/Database/Live/DeleteTest.php b/tests/system/Database/Live/DeleteTest.php
index 4383d32b78a0..65b6212e000c 100644
--- a/tests/system/Database/Live/DeleteTest.php
+++ b/tests/system/Database/Live/DeleteTest.php
@@ -67,7 +67,7 @@ public function testDeleteWithLimit(): void
         try {
             $this->db->table('user')->delete(['country' => 'US'], 1);
         } catch (DatabaseException $e) {
-            if (strpos($e->getMessage(), 'does not allow LIMITs on DELETE queries.') !== false) {
+            if (str_contains($e->getMessage(), 'does not allow LIMITs on DELETE queries.')) {
                 return;
             }
         }
diff --git a/tests/system/Database/Live/GetTest.php b/tests/system/Database/Live/GetTest.php
index 7ee169d55843..885a2ebc239b 100644
--- a/tests/system/Database/Live/GetTest.php
+++ b/tests/system/Database/Live/GetTest.php
@@ -239,7 +239,7 @@ public function testGetRowWithCustomReturnType(): void
             public $deleted_at;
         };
 
-        $user = $this->db->table('user')->get()->getRow(0, get_class($testClass));
+        $user = $this->db->table('user')->get()->getRow(0, $testClass::class);
 
         $this->assertSame('Derek Jones', $user->name);
     }
diff --git a/tests/system/Database/Live/PreparedQueryTest.php b/tests/system/Database/Live/PreparedQueryTest.php
index 2bb2c7419696..1b97b8543511 100644
--- a/tests/system/Database/Live/PreparedQueryTest.php
+++ b/tests/system/Database/Live/PreparedQueryTest.php
@@ -45,7 +45,7 @@ protected function tearDown(): void
 
         try {
             $this->query->close();
-        } catch (BadMethodCallException $e) {
+        } catch (BadMethodCallException) {
             $this->query = null;
         }
     }
diff --git a/tests/system/Database/Live/UpdateTest.php b/tests/system/Database/Live/UpdateTest.php
index 1c6ae8a430b6..dc6701f7f3d9 100644
--- a/tests/system/Database/Live/UpdateTest.php
+++ b/tests/system/Database/Live/UpdateTest.php
@@ -69,7 +69,7 @@ public function testUpdateSetsAllWithoutWhereAndLimit(): void
 
             $this->assertSame('Richard A Causey', $result[2]->name);
             $this->assertSame('Chris Martin', $result[3]->name);
-        } catch (DatabaseException $e) {
+        } catch (DatabaseException) {
             // This DB doesn't support Where and Limit together
             // but we don't want it called a "Risky" test.
             $this->assertTrue(true);
@@ -104,7 +104,7 @@ public function testUpdateWithWhereAndLimit(): void
             $this->assertSame('Ahmadinejad', $result[1]->name);
             $this->assertSame('Richard A Causey', $result[2]->name);
             $this->assertSame('Chris Martin', $result[3]->name);
-        } catch (DatabaseException $e) {
+        } catch (DatabaseException) {
             // This DB doesn't support Where and Limit together
             // but we don't want it called a "Risky" test.
             $this->assertTrue(true);
diff --git a/tests/system/Debug/ExceptionsTest.php b/tests/system/Debug/ExceptionsTest.php
index 4a30a32f1133..0a403c8df557 100644
--- a/tests/system/Debug/ExceptionsTest.php
+++ b/tests/system/Debug/ExceptionsTest.php
@@ -73,7 +73,7 @@ public function testDeprecationsOnPhp81DoNotThrow(): void
         try {
             strlen($maybeNull);
             $this->assertLogContains('error', '[DEPRECATED] strlen(): ');
-        } catch (ErrorException $e) {
+        } catch (ErrorException) {
             $this->fail('The catch block should not be reached.');
         } finally {
             restore_error_handler();
diff --git a/tests/system/HTTP/ContentSecurityPolicyTest.php b/tests/system/HTTP/ContentSecurityPolicyTest.php
index 1a92190e4e10..8d1e8bb7c463 100644
--- a/tests/system/HTTP/ContentSecurityPolicyTest.php
+++ b/tests/system/HTTP/ContentSecurityPolicyTest.php
@@ -469,7 +469,7 @@ public function testBodyScriptNonce(): void
         $result     = $this->work($body);
         $nonceStyle = array_filter(
             $this->getPrivateProperty($this->csp, 'styleSrc'),
-            static fn ($value) => strpos($value, 'nonce-') === 0
+            static fn ($value) => str_starts_with($value, 'nonce-')
         );
 
         $this->assertStringContainsString('nonce=', $this->response->getBody());
@@ -546,7 +546,7 @@ public function testBodyStyleNonce(): void
         $result      = $this->work($body);
         $nonceScript = array_filter(
             $this->getPrivateProperty($this->csp, 'scriptSrc'),
-            static fn ($value) => strpos($value, 'nonce-') === 0
+            static fn ($value) => str_starts_with($value, 'nonce-')
         );
 
         $this->assertStringContainsString('nonce=', $this->response->getBody());
diff --git a/tests/system/Models/DeleteModelTest.php b/tests/system/Models/DeleteModelTest.php
index 121ff40600fe..ac7d0ae6a894 100644
--- a/tests/system/Models/DeleteModelTest.php
+++ b/tests/system/Models/DeleteModelTest.php
@@ -191,7 +191,7 @@ public function testDontDeleteRowsWhenSoftDeleteParamIsEmpty($emptyValue): void
 
         try {
             $this->createModel(UserModel::class)->delete($emptyValue);
-        } catch (DatabaseException $e) {
+        } catch (DatabaseException) {
             // Do nothing.
         }
 

From 4ea31f4862f632ed1ae28dad09fdf848536e833a Mon Sep 17 00:00:00 2001
From: kenjis <kenji.uui@gmail.com>
Date: Sun, 24 Sep 2023 05:32:38 +0900
Subject: [PATCH 03/21] style: add space after !

---
 app/Views/errors/html/error_exception.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/app/Views/errors/html/error_exception.php b/app/Views/errors/html/error_exception.php
index 98b48b9b6834..2e5571e97e4b 100644
--- a/app/Views/errors/html/error_exception.php
+++ b/app/Views/errors/html/error_exception.php
@@ -115,7 +115,7 @@
                                         <?php
                                         $params = null;
                                         // Reflection by name is not available for closure function
-                                        if (!str_ends_with($row['function'], '}')) {
+                                        if (! str_ends_with($row['function'], '}')) {
                                             $mirror = isset($row['class']) ? new ReflectionMethod($row['class'], $row['function']) : new ReflectionFunction($row['function']);
                                             $params = $mirror->getParameters();
                                         }

From 7be67f7582b5f17c3f43853b1779715851ed533f Mon Sep 17 00:00:00 2001
From: kenjis <kenji.uui@gmail.com>
Date: Mon, 25 Sep 2023 06:17:16 +0900
Subject: [PATCH 04/21] docs: add comment manually

---
 system/Cache/Handlers/PredisHandler.php | 6 +++++-
 system/Cache/Handlers/RedisHandler.php  | 6 +++++-
 system/Common.php                       | 1 +
 3 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/system/Cache/Handlers/PredisHandler.php b/system/Cache/Handlers/PredisHandler.php
index d9b3701517ad..cdebd7487d8a 100644
--- a/system/Cache/Handlers/PredisHandler.php
+++ b/system/Cache/Handlers/PredisHandler.php
@@ -88,7 +88,11 @@ public function get(string $key)
 
         return match ($data['__ci_type']) {
             'array', 'object' => unserialize($data['__ci_value']),
-            'boolean', 'integer', 'double', 'string', 'NULL' => settype($data['__ci_value'], $data['__ci_type']) ? $data['__ci_value'] : null,
+            'boolean',
+            'integer',
+            'double', // Yes, 'double' is returned and NOT 'float'
+            'string',
+            'NULL'  => settype($data['__ci_value'], $data['__ci_type']) ? $data['__ci_value'] : null,
             default => null,
         };
     }
diff --git a/system/Cache/Handlers/RedisHandler.php b/system/Cache/Handlers/RedisHandler.php
index bbba78eb1b9b..05957cb4e0cf 100644
--- a/system/Cache/Handlers/RedisHandler.php
+++ b/system/Cache/Handlers/RedisHandler.php
@@ -114,7 +114,11 @@ public function get(string $key)
 
         return match ($data['__ci_type']) {
             'array', 'object' => unserialize($data['__ci_value']),
-            'boolean', 'integer', 'double', 'string', 'NULL' => settype($data['__ci_value'], $data['__ci_type']) ? $data['__ci_value'] : null,
+            'boolean',
+            'integer',
+            'double', // Yes, 'double' is returned and NOT 'float'
+            'string',
+            'NULL'  => settype($data['__ci_value'], $data['__ci_type']) ? $data['__ci_value'] : null,
             default => null,
         };
     }
diff --git a/system/Common.php b/system/Common.php
index 66115c819164..1e6780298e83 100644
--- a/system/Common.php
+++ b/system/Common.php
@@ -371,6 +371,7 @@ function env(string $key, $default = null)
             return $default;
         }
 
+        // Handle any boolean values
         return match (strtolower($value)) {
             'true'  => true,
             'false' => false,

From 27a2cd190179708e897c850f8416346aa3554a17 Mon Sep 17 00:00:00 2001
From: kenjis <kenji.uui@gmail.com>
Date: Fri, 6 Oct 2023 14:37:31 +0900
Subject: [PATCH 05/21] refactor: run rector again

---
 tests/system/Database/Live/ForgeTest.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tests/system/Database/Live/ForgeTest.php b/tests/system/Database/Live/ForgeTest.php
index 626660ee7246..c96cc62154bb 100644
--- a/tests/system/Database/Live/ForgeTest.php
+++ b/tests/system/Database/Live/ForgeTest.php
@@ -941,7 +941,7 @@ public function testAddFields(): void
                 ],
             ];
 
-            if (version_compare($this->db->getVersion(), '8.0.17', '>=') && strpos($this->db->getVersion(), 'MariaDB') === false) {
+            if (version_compare($this->db->getVersion(), '8.0.17', '>=') && ! str_contains($this->db->getVersion(), 'MariaDB')) {
                 // As of MySQL 8.0.17, the display width attribute for integer data types
                 // is deprecated and is not reported back anymore.
                 // @see https://dev.mysql.com/doc/refman/8.0/en/numeric-type-attributes.html

From 97014cf8e0f1f4be663273ece2e92cf97f4e809b Mon Sep 17 00:00:00 2001
From: kenjis <kenji.uui@gmail.com>
Date: Sat, 21 Oct 2023 12:50:08 +0900
Subject: [PATCH 06/21] chore: use LevelSetList::UP_TO_PHP_81

---
 rector.php | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/rector.php b/rector.php
index 2b928390fca9..ad7df4d42463 100644
--- a/rector.php
+++ b/rector.php
@@ -40,6 +40,9 @@
 use Rector\Php80\Rector\Class_\AnnotationToAttributeRector;
 use Rector\Php80\Rector\Class_\ClassPropertyAssignToConstructorPromotionRector;
 use Rector\Php80\Rector\FunctionLike\MixedTypeRector;
+use Rector\Php81\Rector\ClassConst\FinalizePublicClassConstantRector;
+use Rector\Php81\Rector\FuncCall\NullToStrictStringFuncCallArgRector;
+use Rector\Php81\Rector\Property\ReadOnlyPropertyRector;
 use Rector\PHPUnit\AnnotationsToAttributes\Rector\Class_\AnnotationWithValueToAttributeRector;
 use Rector\PHPUnit\AnnotationsToAttributes\Rector\Class_\CoversAnnotationWithValueToAttributeRector;
 use Rector\PHPUnit\AnnotationsToAttributes\Rector\ClassMethod\DataProviderAnnotationToAttributeRector;
@@ -50,6 +53,7 @@
 use Rector\Set\ValueObject\LevelSetList;
 use Rector\Set\ValueObject\SetList;
 use Rector\Strict\Rector\If_\BooleanInIfConditionRuleFixerRector;
+use Rector\TypeDeclaration\Rector\ClassMethod\ReturnNeverTypeRector;
 use Utils\Rector\PassStrictParameterToFunctionParameterRector;
 use Utils\Rector\RemoveErrorSuppressInTryCatchStmtsRector;
 use Utils\Rector\UnderscoreToCamelCaseVariableNameRector;
@@ -57,7 +61,7 @@
 return static function (RectorConfig $rectorConfig): void {
     $rectorConfig->sets([
         SetList::DEAD_CODE,
-        LevelSetList::UP_TO_PHP_80,
+        LevelSetList::UP_TO_PHP_81,
         PHPUnitSetList::PHPUNIT_CODE_QUALITY,
         PHPUnitSetList::PHPUNIT_100,
     ]);
@@ -85,6 +89,7 @@
         __DIR__ . '/tests/system/Config/fixtures',
         __DIR__ . '/tests/system/Filters/fixtures',
         __DIR__ . '/tests/_support',
+
         JsonThrowOnErrorRector::class,
         YieldDataProviderRector::class,
 
@@ -122,6 +127,14 @@
         ClassPropertyAssignToConstructorPromotionRector::class,
         MixedTypeRector::class,
 
+        // PHP 8.1 features but cause breaking changes
+        ReadOnlyPropertyRector::class,
+        FinalizePublicClassConstantRector::class,
+        ReturnNeverTypeRector::class,
+
+        // Unnecessary (string) is inserted
+        NullToStrictStringFuncCallArgRector::class,
+
         // PHPUnit 10 (requires PHP 8.1) features
         DataProviderAnnotationToAttributeRector::class,
         DependsAnnotationWithValueToAttributeRector::class,

From b8012cfe3320b1d278e9378aec087009f5f0eca7 Mon Sep 17 00:00:00 2001
From: kenjis <kenji.uui@gmail.com>
Date: Sat, 21 Oct 2023 13:28:54 +0900
Subject: [PATCH 07/21] refactor: run rector

---
 system/Autoloader/Autoloader.php           | 10 +++++-----
 system/Config/AutoloadConfig.php           |  4 ++--
 system/Config/View.php                     |  4 ++--
 system/Database/BaseConnection.php         |  2 +-
 system/Debug/Exceptions.php                |  4 ++--
 system/Email/Email.php                     |  5 +----
 system/Entity/Entity.php                   |  2 +-
 system/Filters/InvalidChars.php            |  4 ++--
 system/Typography/Typography.php           |  6 +++---
 tests/system/Events/EventsTest.php         |  2 +-
 tests/system/Format/FormatTest.php         | 10 ++--------
 tests/system/Validation/ValidationTest.php |  6 +++---
 12 files changed, 25 insertions(+), 34 deletions(-)

diff --git a/system/Autoloader/Autoloader.php b/system/Autoloader/Autoloader.php
index bae6e95c878a..b8b235680532 100644
--- a/system/Autoloader/Autoloader.php
+++ b/system/Autoloader/Autoloader.php
@@ -156,10 +156,10 @@ private function loadComposerAutoloader(Modules $modules): void
     public function register()
     {
         // Register classmap loader for the files in our class map.
-        spl_autoload_register([$this, 'loadClassmap'], true);
+        spl_autoload_register($this->loadClassmap(...), true);
 
         // Register the PSR-4 autoloader.
-        spl_autoload_register([$this, 'loadClass'], true);
+        spl_autoload_register($this->loadClass(...), true);
 
         // Load our non-class files
         foreach ($this->files as $file) {
@@ -174,8 +174,8 @@ public function register()
      */
     public function unregister(): void
     {
-        spl_autoload_unregister([$this, 'loadClass']);
-        spl_autoload_unregister([$this, 'loadClassmap']);
+        spl_autoload_unregister($this->loadClass(...));
+        spl_autoload_unregister($this->loadClassmap(...));
     }
 
     /**
@@ -465,7 +465,7 @@ protected function discoverComposerNamespaces()
             $newPaths[rtrim($key, '\\ ')] = $value;
         }
 
-        $this->prefixes = array_merge($this->prefixes, $newPaths);
+        $this->prefixes = [...$this->prefixes, ...$newPaths];
         $this->classmap = array_merge($this->classmap, $classes);
     }
 
diff --git a/system/Config/AutoloadConfig.php b/system/Config/AutoloadConfig.php
index eb210f626d9a..411f9bd41760 100644
--- a/system/Config/AutoloadConfig.php
+++ b/system/Config/AutoloadConfig.php
@@ -144,8 +144,8 @@ public function __construct()
             $this->classmap['CIDatabaseTestCase']         = SYSTEMPATH . 'Test/CIDatabaseTestCase.php';
         }
 
-        $this->psr4     = array_merge($this->corePsr4, $this->psr4);
-        $this->classmap = array_merge($this->coreClassmap, $this->classmap);
+        $this->psr4     = [...$this->corePsr4, ...$this->psr4];
+        $this->classmap = [...$this->coreClassmap, ...$this->classmap];
         $this->files    = [...$this->coreFiles, ...$this->files];
     }
 }
diff --git a/system/Config/View.php b/system/Config/View.php
index 101b67f580d0..4aff08471ac0 100644
--- a/system/Config/View.php
+++ b/system/Config/View.php
@@ -122,8 +122,8 @@ class View extends BaseConfig
      */
     public function __construct()
     {
-        $this->filters = array_merge($this->coreFilters, $this->filters);
-        $this->plugins = array_merge($this->corePlugins, $this->plugins);
+        $this->filters = [...$this->coreFilters, ...$this->filters];
+        $this->plugins = [...$this->corePlugins, ...$this->plugins];
 
         parent::__construct();
     }
diff --git a/system/Database/BaseConnection.php b/system/Database/BaseConnection.php
index fd2c278a084f..5e40aee5e784 100644
--- a/system/Database/BaseConnection.php
+++ b/system/Database/BaseConnection.php
@@ -1262,7 +1262,7 @@ abstract public function affectedRows(): int;
     public function escape($str)
     {
         if (is_array($str)) {
-            return array_map([&$this, 'escape'], $str);
+            return array_map($this->escape(...), $str);
         }
 
         /** @psalm-suppress NoValue I don't know why ERROR. */
diff --git a/system/Debug/Exceptions.php b/system/Debug/Exceptions.php
index 0c00db0e40e1..2ae5890c6acb 100644
--- a/system/Debug/Exceptions.php
+++ b/system/Debug/Exceptions.php
@@ -106,8 +106,8 @@ public function __construct(ExceptionsConfig $config)
      */
     public function initialize()
     {
-        set_exception_handler([$this, 'exceptionHandler']);
-        set_error_handler([$this, 'errorHandler']);
+        set_exception_handler($this->exceptionHandler(...));
+        set_error_handler($this->errorHandler(...));
         register_shutdown_function([$this, 'shutdownHandler']);
     }
 
diff --git a/system/Email/Email.php b/system/Email/Email.php
index 9246da0cd794..6861d953fe2e 100644
--- a/system/Email/Email.php
+++ b/system/Email/Email.php
@@ -1644,10 +1644,7 @@ protected function unwrapSpecials()
     {
         $this->finalBody = preg_replace_callback(
             '/\{unwrap\}(.*?)\{\/unwrap\}/si',
-            [
-                $this,
-                'removeNLCallback',
-            ],
+            $this->removeNLCallback(...),
             $this->finalBody
         );
     }
diff --git a/system/Entity/Entity.php b/system/Entity/Entity.php
index 12db7a97a059..32c2393836dd 100644
--- a/system/Entity/Entity.php
+++ b/system/Entity/Entity.php
@@ -401,7 +401,7 @@ protected function castAs($value, string $attribute, string $method = 'get')
 
         $type = trim($type, '[]');
 
-        $handlers = array_merge($this->defaultCastHandlers, $this->castHandlers);
+        $handlers = [...$this->defaultCastHandlers, ...$this->castHandlers];
 
         if (empty($handlers[$type])) {
             return $value;
diff --git a/system/Filters/InvalidChars.php b/system/Filters/InvalidChars.php
index 93124fdb4e9f..0bddd4862252 100644
--- a/system/Filters/InvalidChars.php
+++ b/system/Filters/InvalidChars.php
@@ -90,7 +90,7 @@ public function after(RequestInterface $request, ResponseInterface $response, $a
     protected function checkEncoding($value)
     {
         if (is_array($value)) {
-            array_map([$this, 'checkEncoding'], $value);
+            array_map($this->checkEncoding(...), $value);
 
             return $value;
         }
@@ -112,7 +112,7 @@ protected function checkEncoding($value)
     protected function checkControl($value)
     {
         if (is_array($value)) {
-            array_map([$this, 'checkControl'], $value);
+            array_map($this->checkControl(...), $value);
 
             return $value;
         }
diff --git a/system/Typography/Typography.php b/system/Typography/Typography.php
index 1442c2f6e51a..301f03227f53 100644
--- a/system/Typography/Typography.php
+++ b/system/Typography/Typography.php
@@ -104,15 +104,15 @@ public function autoTypography(string $str, bool $reduceLinebreaks = false): str
         // match and yank <pre> tags if they exist.  It's cheaper to do this separately since most content will
         // not contain <pre> tags, and it keeps the PCRE patterns below simpler and faster
         if (str_contains($str, '<pre')) {
-            $str = preg_replace_callback('#<pre.*?>.*?</pre>#si', [$this, 'protectCharacters'], $str);
+            $str = preg_replace_callback('#<pre.*?>.*?</pre>#si', $this->protectCharacters(...), $str);
         }
 
         // Convert quotes within tags to temporary markers.
-        $str = preg_replace_callback('#<.+?>#si', [$this, 'protectCharacters'], $str);
+        $str = preg_replace_callback('#<.+?>#si', $this->protectCharacters(...), $str);
 
         // Do the same with braces if necessary
         if ($this->protectBracedQuotes === false) {
-            $str = preg_replace_callback('#\{.+?\}#si', [$this, 'protectCharacters'], $str);
+            $str = preg_replace_callback('#\{.+?\}#si', $this->protectCharacters(...), $str);
         }
 
         // Convert "ignore" tags to temporary marker.  The parser splits out the string at every tag
diff --git a/tests/system/Events/EventsTest.php b/tests/system/Events/EventsTest.php
index d34afda0c9e4..b94c901ba3b9 100644
--- a/tests/system/Events/EventsTest.php
+++ b/tests/system/Events/EventsTest.php
@@ -289,7 +289,7 @@ public function hold(string $value): void
             }
         };
 
-        Events::on('foo', [$box, 'hold']);
+        Events::on('foo', $box->hold(...));
 
         $this->assertTrue(Events::trigger('foo', 'bar'));
 
diff --git a/tests/system/Format/FormatTest.php b/tests/system/Format/FormatTest.php
index 7cb7d888ed9c..193fb56ac927 100644
--- a/tests/system/Format/FormatTest.php
+++ b/tests/system/Format/FormatTest.php
@@ -52,10 +52,7 @@ public function testGetFormatterExpectsExceptionOnUndefinedMime(): void
 
     public function testGetFormatterExpectsExceptionOnUndefinedClass(): void
     {
-        $this->format->getConfig()->formatters = array_merge(
-            $this->format->getConfig()->formatters,
-            ['text/xml' => 'App\Foo']
-        );
+        $this->format->getConfig()->formatters = [...$this->format->getConfig()->formatters, 'text/xml' => 'App\Foo'];
 
         $this->expectException(FormatException::class);
         $this->expectExceptionMessage('"App\Foo" is not a valid Formatter class.');
@@ -64,10 +61,7 @@ public function testGetFormatterExpectsExceptionOnUndefinedClass(): void
 
     public function testGetFormatterExpectsExceptionOnClassNotImplementingFormatterInterface(): void
     {
-        $this->format->getConfig()->formatters = array_merge(
-            $this->format->getConfig()->formatters,
-            ['text/xml' => URI::class]
-        );
+        $this->format->getConfig()->formatters = [...$this->format->getConfig()->formatters, 'text/xml' => URI::class];
 
         $this->expectException(FormatException::class);
         $this->expectExceptionMessage('"CodeIgniter\HTTP\URI" is not a valid Formatter class.');
diff --git a/tests/system/Validation/ValidationTest.php b/tests/system/Validation/ValidationTest.php
index 28bee306ab88..a98071e6c2a0 100644
--- a/tests/system/Validation/ValidationTest.php
+++ b/tests/system/Validation/ValidationTest.php
@@ -358,7 +358,7 @@ public function testCallableRule(): void
     {
         $this->validation->setRules(
             [
-                'foo' => ['required', [$this, 'rule1']],
+                'foo' => ['required', $this->rule1(...)],
             ],
             [
                 // Errors
@@ -401,7 +401,7 @@ public function testCallableRuleWithParamError(): void
         $this->validation->setRules([
             'foo' => [
                 'required',
-                [$this, 'rule2'],
+                $this->rule2(...),
             ],
         ]);
 
@@ -421,7 +421,7 @@ public function testCallableRuleWithLabel(): void
         $this->validation->setRules([
             'secret' => [
                 'label'  => 'シークレット',
-                'rules'  => ['required', [$this, 'rule1']],
+                'rules'  => ['required', $this->rule1(...)],
                 'errors' => [
                     // Specify the array key for the callable rule.
                     1 => 'The {field} is invalid',

From eab4f5b08f11f5cc5609c2ec4f7eaa95f9477ddc Mon Sep 17 00:00:00 2001
From: kenjis <kenji.uui@gmail.com>
Date: Sat, 21 Oct 2023 13:40:43 +0900
Subject: [PATCH 08/21] docs: fix @param for Email::removeNLCallback()

---
 system/Email/Email.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/system/Email/Email.php b/system/Email/Email.php
index 6861d953fe2e..649e1188f35e 100644
--- a/system/Email/Email.php
+++ b/system/Email/Email.php
@@ -1652,7 +1652,7 @@ protected function unwrapSpecials()
     /**
      * Strip line-breaks via callback
      *
-     * @param string $matches
+     * @param array<int|string, string> $matches
      *
      * @return string
      */

From 7071b4e7f6d97ad18e06b5060c8c5efcbe68a5a9 Mon Sep 17 00:00:00 2001
From: kenjis <kenji.uui@gmail.com>
Date: Sat, 21 Oct 2023 13:42:43 +0900
Subject: [PATCH 09/21] test: run ReturnNeverTypeRector

---
 tests/system/CodeIgniterTest.php              | 2 +-
 tests/system/Debug/TimerTest.php              | 2 +-
 tests/system/HTTP/DownloadResponseTest.php    | 4 ++--
 tests/system/HTTP/SiteURITest.php             | 2 +-
 tests/system/Test/ControllerTestTraitTest.php | 2 +-
 5 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/tests/system/CodeIgniterTest.php b/tests/system/CodeIgniterTest.php
index ef9a42cc2f33..16b3164e71d2 100644
--- a/tests/system/CodeIgniterTest.php
+++ b/tests/system/CodeIgniterTest.php
@@ -598,7 +598,7 @@ public function testRedirectExceptionDeprecated(): void
 
         // Inject mock router.
         $routes = Services::routes();
-        $routes->get('/', static function () {
+        $routes->get('/', static function (): never {
             throw new RedirectException('redirect-exception', 503);
         });
 
diff --git a/tests/system/Debug/TimerTest.php b/tests/system/Debug/TimerTest.php
index 2be069062d9c..894247eebbd3 100644
--- a/tests/system/Debug/TimerTest.php
+++ b/tests/system/Debug/TimerTest.php
@@ -166,7 +166,7 @@ public function testRecordThrowsException(): void
         $this->expectException(RuntimeException::class);
 
         $timer = new Timer();
-        $timer->record('ex', static function (): void { throw new RuntimeException(); });
+        $timer->record('ex', static function (): never { throw new RuntimeException(); });
     }
 
     public function testRecordThrowsErrorOnCallableWithParams(): void
diff --git a/tests/system/HTTP/DownloadResponseTest.php b/tests/system/HTTP/DownloadResponseTest.php
index 975c063927e3..23093f2e4ccb 100644
--- a/tests/system/HTTP/DownloadResponseTest.php
+++ b/tests/system/HTTP/DownloadResponseTest.php
@@ -38,7 +38,7 @@ public function testCanGetStatusCode(): void
         $this->assertSame(200, $response->getStatusCode());
     }
 
-    public function testCantSetStatusCode(): void
+    public function testCantSetStatusCode(): never
     {
         $response = new DownloadResponse('unit-test.txt', true);
 
@@ -137,7 +137,7 @@ public function testNoCache(): void
         $this->assertSame('private, no-transform, no-store, must-revalidate', $response->getHeaderLine('Cache-control'));
     }
 
-    public function testCantSetCache(): void
+    public function testCantSetCache(): never
     {
         $response = new DownloadResponse('unit-test.txt', true);
 
diff --git a/tests/system/HTTP/SiteURITest.php b/tests/system/HTTP/SiteURITest.php
index f839b51c0771..0143fa5ecdc8 100644
--- a/tests/system/HTTP/SiteURITest.php
+++ b/tests/system/HTTP/SiteURITest.php
@@ -473,7 +473,7 @@ public function testGetTotalSegments()
         $this->assertSame(0, $uri->getTotalSegments());
     }
 
-    public function testSetURI()
+    public function testSetURI(): never
     {
         $this->expectException(BadMethodCallException::class);
 
diff --git a/tests/system/Test/ControllerTestTraitTest.php b/tests/system/Test/ControllerTestTraitTest.php
index ac470ce3ce56..055661e9a909 100644
--- a/tests/system/Test/ControllerTestTraitTest.php
+++ b/tests/system/Test/ControllerTestTraitTest.php
@@ -248,7 +248,7 @@ public function testRedirectRoute(): void
     public function testUsesRequestBody(): void
     {
         $this->controller = new class () extends Controller {
-            public function throwsBody(): void
+            public function throwsBody(): never
             {
                 throw new Exception($this->request->getBody());
             }

From dd22f03fcb1f78231a5840b0f120d2bebaf80c70 Mon Sep 17 00:00:00 2001
From: kenjis <kenji.uui@gmail.com>
Date: Sat, 21 Oct 2023 13:52:43 +0900
Subject: [PATCH 10/21] chore: enable ReturnNeverTypeRector to the extent that
 existing product codes are not changed

---
 rector.php | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/rector.php b/rector.php
index ad7df4d42463..bc497af3397c 100644
--- a/rector.php
+++ b/rector.php
@@ -130,7 +130,19 @@
         // PHP 8.1 features but cause breaking changes
         ReadOnlyPropertyRector::class,
         FinalizePublicClassConstantRector::class,
-        ReturnNeverTypeRector::class,
+        ReturnNeverTypeRector::class => [
+            __DIR__ . '/system/Cache/Handlers/MemcachedHandler.php',
+            __DIR__ . '/system/Cache/Handlers/WincacheHandler.php',
+            __DIR__ . '/system/CodeIgniter.php',
+            __DIR__ . '/system/Database/MySQLi/Utils.php',
+            __DIR__ . '/system/Database/OCI8/Utils.php',
+            __DIR__ . '/system/Database/Postgre/Utils.php',
+            __DIR__ . '/system/Database/SQLSRV/Utils.php',
+            __DIR__ . '/system/Database/SQLite3/Utils.php',
+            __DIR__ . '/system/HTTP/DownloadResponse.php',
+            __DIR__ . '/system/HTTP/SiteURI.php',
+            __DIR__ . '/system/Helpers/kint_helper.php',
+        ],
 
         // Unnecessary (string) is inserted
         NullToStrictStringFuncCallArgRector::class,

From 356cb97f6dcaa721fa07a77fc927b5d3329b971b Mon Sep 17 00:00:00 2001
From: kenjis <kenji.uui@gmail.com>
Date: Sat, 21 Oct 2023 14:01:59 +0900
Subject: [PATCH 11/21] test: run FinalizePublicClassConstantRector

---
 tests/system/Validation/FormatRulesTest.php | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tests/system/Validation/FormatRulesTest.php b/tests/system/Validation/FormatRulesTest.php
index eb25696c4fea..55ec7d5e25f4 100644
--- a/tests/system/Validation/FormatRulesTest.php
+++ b/tests/system/Validation/FormatRulesTest.php
@@ -25,8 +25,8 @@
  */
 class FormatRulesTest extends CIUnitTestCase
 {
-    public const ALPHABET     = 'abcdefghijklmnopqrstuvwxyzABCDEFGHLIJKLMNOPQRSTUVWXYZ';
-    public const ALPHANUMERIC = 'abcdefghijklmnopqrstuvwxyzABCDEFGHLIJKLMNOPQRSTUVWXYZ0123456789';
+    final public const ALPHABET     = 'abcdefghijklmnopqrstuvwxyzABCDEFGHLIJKLMNOPQRSTUVWXYZ';
+    final public const ALPHANUMERIC = 'abcdefghijklmnopqrstuvwxyzABCDEFGHLIJKLMNOPQRSTUVWXYZ0123456789';
 
     protected Validation $validation;
     protected array $config = [

From 19b1614a312f14e33a9a2cb1cddb90d457e6acd4 Mon Sep 17 00:00:00 2001
From: kenjis <kenji.uui@gmail.com>
Date: Sat, 21 Oct 2023 14:02:17 +0900
Subject: [PATCH 12/21] chore: enable FinalizePublicClassConstantRector to the
 extent that existing product codes are not changed

---
 rector.php | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/rector.php b/rector.php
index bc497af3397c..6f6c2cb3a694 100644
--- a/rector.php
+++ b/rector.php
@@ -129,7 +129,15 @@
 
         // PHP 8.1 features but cause breaking changes
         ReadOnlyPropertyRector::class,
-        FinalizePublicClassConstantRector::class,
+        FinalizePublicClassConstantRector::class => [
+            __DIR__ . '/system/Cache/Handlers/BaseHandler.php',
+            __DIR__ . '/system/Cache/Handlers/FileHandler.php',
+            __DIR__ . '/system/CodeIgniter.php',
+            __DIR__ . '/system/Events/Events.php',
+            __DIR__ . '/system/Log/Handlers/ChromeLoggerHandler.php',
+            __DIR__ . '/system/Log/Handlers/ErrorlogHandler.php',
+            __DIR__ . '/system/Security/Security.php',
+        ],
         ReturnNeverTypeRector::class => [
             __DIR__ . '/system/Cache/Handlers/MemcachedHandler.php',
             __DIR__ . '/system/Cache/Handlers/WincacheHandler.php',

From 4d246c674346dfb961cd58ecb1b5b22c218381ae Mon Sep 17 00:00:00 2001
From: kenjis <kenji.uui@gmail.com>
Date: Sat, 21 Oct 2023 14:10:04 +0900
Subject: [PATCH 13/21] refactor: apply ReadOnlyPropertyRector

---
 rector.php                                             |  2 --
 system/Autoloader/FileLocatorCached.php                |  2 +-
 system/Cache/ResponseCache.php                         |  2 +-
 .../Commands/Utilities/Routes/AutoRouteCollector.php   |  6 +++---
 .../Routes/AutoRouterImproved/AutoRouteCollector.php   | 10 +++++-----
 .../AutoRouterImproved/ControllerMethodReader.php      |  4 ++--
 system/Commands/Utilities/Routes/ControllerFinder.php  |  4 ++--
 .../Utilities/Routes/ControllerMethodReader.php        |  2 +-
 system/Commands/Utilities/Routes/FilterCollector.php   |  2 +-
 system/Commands/Utilities/Routes/FilterFinder.php      |  4 ++--
 .../Commands/Utilities/Routes/SampleURIGenerator.php   |  2 +-
 system/HTTP/CURLRequest.php                            |  4 ++--
 system/HTTP/DownloadResponse.php                       |  2 +-
 system/HTTP/SiteURI.php                                |  2 +-
 system/HTTP/SiteURIFactory.php                         |  4 ++--
 system/Publisher/Publisher.php                         |  4 ++--
 system/Router/AutoRouter.php                           |  6 +++---
 system/Router/AutoRouterImproved.php                   |  8 ++++----
 system/Router/DefinedRouteCollector.php                |  2 +-
 system/Security/Security.php                           |  2 +-
 system/Validation/StrictRules/CreditCardRules.php      |  2 +-
 system/Validation/StrictRules/FormatRules.php          |  2 +-
 system/Validation/StrictRules/Rules.php                |  2 +-
 tests/system/Cache/Handlers/FileHandlerTest.php        |  2 +-
 .../Rector/UnderscoreToCamelCaseVariableNameRector.php |  2 +-
 25 files changed, 41 insertions(+), 43 deletions(-)

diff --git a/rector.php b/rector.php
index 6f6c2cb3a694..bcf553e24116 100644
--- a/rector.php
+++ b/rector.php
@@ -42,7 +42,6 @@
 use Rector\Php80\Rector\FunctionLike\MixedTypeRector;
 use Rector\Php81\Rector\ClassConst\FinalizePublicClassConstantRector;
 use Rector\Php81\Rector\FuncCall\NullToStrictStringFuncCallArgRector;
-use Rector\Php81\Rector\Property\ReadOnlyPropertyRector;
 use Rector\PHPUnit\AnnotationsToAttributes\Rector\Class_\AnnotationWithValueToAttributeRector;
 use Rector\PHPUnit\AnnotationsToAttributes\Rector\Class_\CoversAnnotationWithValueToAttributeRector;
 use Rector\PHPUnit\AnnotationsToAttributes\Rector\ClassMethod\DataProviderAnnotationToAttributeRector;
@@ -128,7 +127,6 @@
         MixedTypeRector::class,
 
         // PHP 8.1 features but cause breaking changes
-        ReadOnlyPropertyRector::class,
         FinalizePublicClassConstantRector::class => [
             __DIR__ . '/system/Cache/Handlers/BaseHandler.php',
             __DIR__ . '/system/Cache/Handlers/FileHandler.php',
diff --git a/system/Autoloader/FileLocatorCached.php b/system/Autoloader/FileLocatorCached.php
index 8bc8d1e85ee9..844e06ca818f 100644
--- a/system/Autoloader/FileLocatorCached.php
+++ b/system/Autoloader/FileLocatorCached.php
@@ -21,7 +21,7 @@
  */
 final class FileLocatorCached implements FileLocatorInterface
 {
-    private FileLocator $locator;
+    private readonly FileLocator $locator;
 
     /**
      * @var CacheInterface|FileVarExportHandler
diff --git a/system/Cache/ResponseCache.php b/system/Cache/ResponseCache.php
index 6e8e8b4887b1..83ffdfeca1c3 100644
--- a/system/Cache/ResponseCache.php
+++ b/system/Cache/ResponseCache.php
@@ -47,7 +47,7 @@ final class ResponseCache
      */
     private int $ttl = 0;
 
-    private CacheInterface $cache;
+    private readonly CacheInterface $cache;
 
     public function __construct(CacheConfig $config, CacheInterface $cache)
     {
diff --git a/system/Commands/Utilities/Routes/AutoRouteCollector.php b/system/Commands/Utilities/Routes/AutoRouteCollector.php
index cc45608f21e8..5455951aa809 100644
--- a/system/Commands/Utilities/Routes/AutoRouteCollector.php
+++ b/system/Commands/Utilities/Routes/AutoRouteCollector.php
@@ -21,10 +21,10 @@ final class AutoRouteCollector
     /**
      * @var string namespace to search
      */
-    private string $namespace;
+    private readonly string $namespace;
 
-    private string $defaultController;
-    private string $defaultMethod;
+    private readonly string $defaultController;
+    private readonly string $defaultMethod;
 
     /**
      * @param string $namespace namespace to search
diff --git a/system/Commands/Utilities/Routes/AutoRouterImproved/AutoRouteCollector.php b/system/Commands/Utilities/Routes/AutoRouterImproved/AutoRouteCollector.php
index 18a158cffa4f..e7fe0871e034 100644
--- a/system/Commands/Utilities/Routes/AutoRouterImproved/AutoRouteCollector.php
+++ b/system/Commands/Utilities/Routes/AutoRouterImproved/AutoRouteCollector.php
@@ -24,18 +24,18 @@ final class AutoRouteCollector
     /**
      * @var string namespace to search
      */
-    private string $namespace;
+    private readonly string $namespace;
 
-    private string $defaultController;
-    private string $defaultMethod;
-    private array $httpMethods;
+    private readonly string $defaultController;
+    private readonly string $defaultMethod;
+    private readonly array $httpMethods;
 
     /**
      * List of controllers in Defined Routes that should not be accessed via Auto-Routing.
      *
      * @var class-string[]
      */
-    private array $protectedControllers;
+    private readonly array $protectedControllers;
 
     /**
      * @var string URI prefix for Module Routing
diff --git a/system/Commands/Utilities/Routes/AutoRouterImproved/ControllerMethodReader.php b/system/Commands/Utilities/Routes/AutoRouterImproved/ControllerMethodReader.php
index 460a4a89ccef..6e982d4612d3 100644
--- a/system/Commands/Utilities/Routes/AutoRouterImproved/ControllerMethodReader.php
+++ b/system/Commands/Utilities/Routes/AutoRouterImproved/ControllerMethodReader.php
@@ -24,12 +24,12 @@ final class ControllerMethodReader
     /**
      * @var string the default namespace
      */
-    private string $namespace;
+    private readonly string $namespace;
 
     /**
      * @var list<string>
      */
-    private array $httpMethods;
+    private readonly array $httpMethods;
 
     /**
      * @param string $namespace the default namespace
diff --git a/system/Commands/Utilities/Routes/ControllerFinder.php b/system/Commands/Utilities/Routes/ControllerFinder.php
index 4611051462ea..e9bce1260c46 100644
--- a/system/Commands/Utilities/Routes/ControllerFinder.php
+++ b/system/Commands/Utilities/Routes/ControllerFinder.php
@@ -24,9 +24,9 @@ final class ControllerFinder
     /**
      * @var string namespace to search
      */
-    private string $namespace;
+    private readonly string $namespace;
 
-    private FileLocatorInterface $locator;
+    private readonly FileLocatorInterface $locator;
 
     /**
      * @param string $namespace namespace to search
diff --git a/system/Commands/Utilities/Routes/ControllerMethodReader.php b/system/Commands/Utilities/Routes/ControllerMethodReader.php
index 31bcde12dfb8..f281a2267640 100644
--- a/system/Commands/Utilities/Routes/ControllerMethodReader.php
+++ b/system/Commands/Utilities/Routes/ControllerMethodReader.php
@@ -24,7 +24,7 @@ final class ControllerMethodReader
     /**
      * @var string the default namespace
      */
-    private string $namespace;
+    private readonly string $namespace;
 
     /**
      * @param string $namespace the default namespace
diff --git a/system/Commands/Utilities/Routes/FilterCollector.php b/system/Commands/Utilities/Routes/FilterCollector.php
index 0135a6a53569..0924f08d230b 100644
--- a/system/Commands/Utilities/Routes/FilterCollector.php
+++ b/system/Commands/Utilities/Routes/FilterCollector.php
@@ -29,7 +29,7 @@ final class FilterCollector
      *
      * If set to true, route filters are not found.
      */
-    private bool $resetRoutes;
+    private readonly bool $resetRoutes;
 
     public function __construct(bool $resetRoutes = false)
     {
diff --git a/system/Commands/Utilities/Routes/FilterFinder.php b/system/Commands/Utilities/Routes/FilterFinder.php
index 8788a164ac88..f27e7e8d3d74 100644
--- a/system/Commands/Utilities/Routes/FilterFinder.php
+++ b/system/Commands/Utilities/Routes/FilterFinder.php
@@ -25,8 +25,8 @@
  */
 final class FilterFinder
 {
-    private Router $router;
-    private Filters $filters;
+    private readonly Router $router;
+    private readonly Filters $filters;
 
     public function __construct(?Router $router = null, ?Filters $filters = null)
     {
diff --git a/system/Commands/Utilities/Routes/SampleURIGenerator.php b/system/Commands/Utilities/Routes/SampleURIGenerator.php
index 43d1934438bb..4c4cf0c9112e 100644
--- a/system/Commands/Utilities/Routes/SampleURIGenerator.php
+++ b/system/Commands/Utilities/Routes/SampleURIGenerator.php
@@ -22,7 +22,7 @@
  */
 final class SampleURIGenerator
 {
-    private RouteCollection $routes;
+    private readonly RouteCollection $routes;
 
     /**
      * Sample URI path for placeholder.
diff --git a/system/HTTP/CURLRequest.php b/system/HTTP/CURLRequest.php
index a73796af42b4..8ee1cb7cb920 100644
--- a/system/HTTP/CURLRequest.php
+++ b/system/HTTP/CURLRequest.php
@@ -89,7 +89,7 @@ class CURLRequest extends OutgoingRequest
     /**
      * The default options from the constructor. Applied to all requests.
      */
-    private array $defaultOptions;
+    private readonly array $defaultOptions;
 
     /**
      * Whether share options between requests or not.
@@ -97,7 +97,7 @@ class CURLRequest extends OutgoingRequest
      * If true, all the options won't be reset between requests.
      * It may cause an error request with unnecessary headers.
      */
-    private bool $shareOptions;
+    private readonly bool $shareOptions;
 
     /**
      * Takes an array of options to set the following possible class properties:
diff --git a/system/HTTP/DownloadResponse.php b/system/HTTP/DownloadResponse.php
index 14dc3fec1421..fc077f1a251e 100644
--- a/system/HTTP/DownloadResponse.php
+++ b/system/HTTP/DownloadResponse.php
@@ -36,7 +36,7 @@ class DownloadResponse extends Response
     /**
      * mime set flag
      */
-    private bool $setMime;
+    private readonly bool $setMime;
 
     /**
      * Download for binary
diff --git a/system/HTTP/SiteURI.php b/system/HTTP/SiteURI.php
index 43948ecbf33c..853a2166edab 100644
--- a/system/HTTP/SiteURI.php
+++ b/system/HTTP/SiteURI.php
@@ -27,7 +27,7 @@ class SiteURI extends URI implements Stringable
     /**
      * The current baseURL.
      */
-    private URI $baseURL;
+    private readonly URI $baseURL;
 
     /**
      * The path part of baseURL.
diff --git a/system/HTTP/SiteURIFactory.php b/system/HTTP/SiteURIFactory.php
index fd4921be913c..de1069f6a617 100644
--- a/system/HTTP/SiteURIFactory.php
+++ b/system/HTTP/SiteURIFactory.php
@@ -24,8 +24,8 @@
  */
 final class SiteURIFactory
 {
-    private App $appConfig;
-    private Superglobals $superglobals;
+    private readonly App $appConfig;
+    private readonly Superglobals $superglobals;
 
     public function __construct(App $appConfig, Superglobals $superglobals)
     {
diff --git a/system/Publisher/Publisher.php b/system/Publisher/Publisher.php
index 725c15368354..75e84f45f8ed 100644
--- a/system/Publisher/Publisher.php
+++ b/system/Publisher/Publisher.php
@@ -70,9 +70,9 @@ class Publisher extends FileCollection
      *
      * @var array<string,string>
      */
-    private array $restrictions;
+    private readonly array $restrictions;
 
-    private ContentReplacer $replacer;
+    private readonly ContentReplacer $replacer;
 
     /**
      * Base path to use for the source.
diff --git a/system/Router/AutoRouter.php b/system/Router/AutoRouter.php
index ec4622a15867..4a46275f6227 100644
--- a/system/Router/AutoRouter.php
+++ b/system/Router/AutoRouter.php
@@ -24,7 +24,7 @@ final class AutoRouter implements AutoRouterInterface
      *
      * @var array<string, Closure|string> [routeKey => handler]
      */
-    private array $cliRoutes;
+    private readonly array $cliRoutes;
 
     /**
      * Sub-directory that contains the requested controller class.
@@ -51,12 +51,12 @@ final class AutoRouter implements AutoRouterInterface
     /**
      * HTTP verb for the request.
      */
-    private string $httpVerb;
+    private readonly string $httpVerb;
 
     /**
      * Default namespace for controllers.
      */
-    private string $defaultNamespace;
+    private readonly string $defaultNamespace;
 
     public function __construct(
         array $cliRoutes,
diff --git a/system/Router/AutoRouterImproved.php b/system/Router/AutoRouterImproved.php
index 6d26cf38f4f1..24122105b097 100644
--- a/system/Router/AutoRouterImproved.php
+++ b/system/Router/AutoRouterImproved.php
@@ -29,7 +29,7 @@ final class AutoRouterImproved implements AutoRouterInterface
      *
      * @var class-string[]
      */
-    private array $protectedControllers;
+    private readonly array $protectedControllers;
 
     /**
      * Sub-directory that contains the requested controller class.
@@ -57,7 +57,7 @@ final class AutoRouterImproved implements AutoRouterInterface
      * Whether dashes in URI's should be converted
      * to underscores when determining method names.
      */
-    private bool $translateURIDashes;
+    private readonly bool $translateURIDashes;
 
     /**
      * The namespace for controllers.
@@ -67,12 +67,12 @@ final class AutoRouterImproved implements AutoRouterInterface
     /**
      * The name of the default controller class.
      */
-    private string $defaultController;
+    private readonly string $defaultController;
 
     /**
      * The name of the default method without HTTP verb prefix.
      */
-    private string $defaultMethod;
+    private readonly string $defaultMethod;
 
     /**
      * The URI segments.
diff --git a/system/Router/DefinedRouteCollector.php b/system/Router/DefinedRouteCollector.php
index 598efa6bb4d9..c8f0a93323e9 100644
--- a/system/Router/DefinedRouteCollector.php
+++ b/system/Router/DefinedRouteCollector.php
@@ -21,7 +21,7 @@
  */
 final class DefinedRouteCollector
 {
-    private RouteCollection $routeCollection;
+    private readonly RouteCollection $routeCollection;
 
     public function __construct(RouteCollection $routes)
     {
diff --git a/system/Security/Security.php b/system/Security/Security.php
index 167f864e2bea..9a226a576efd 100644
--- a/system/Security/Security.php
+++ b/system/Security/Security.php
@@ -159,7 +159,7 @@ class Security implements SecurityInterface
      */
     protected $samesite = Cookie::SAMESITE_LAX;
 
-    private IncomingRequest $request;
+    private readonly IncomingRequest $request;
 
     /**
      * CSRF Cookie Name without Prefix
diff --git a/system/Validation/StrictRules/CreditCardRules.php b/system/Validation/StrictRules/CreditCardRules.php
index 2ceacdc6fc37..6512568317ed 100644
--- a/system/Validation/StrictRules/CreditCardRules.php
+++ b/system/Validation/StrictRules/CreditCardRules.php
@@ -25,7 +25,7 @@
  */
 class CreditCardRules
 {
-    private NonStrictCreditCardRules $nonStrictCreditCardRules;
+    private readonly NonStrictCreditCardRules $nonStrictCreditCardRules;
 
     public function __construct()
     {
diff --git a/system/Validation/StrictRules/FormatRules.php b/system/Validation/StrictRules/FormatRules.php
index c186a75b2694..0363f4be4afc 100644
--- a/system/Validation/StrictRules/FormatRules.php
+++ b/system/Validation/StrictRules/FormatRules.php
@@ -22,7 +22,7 @@
  */
 class FormatRules
 {
-    private NonStrictFormatRules $nonStrictFormatRules;
+    private readonly NonStrictFormatRules $nonStrictFormatRules;
 
     public function __construct()
     {
diff --git a/system/Validation/StrictRules/Rules.php b/system/Validation/StrictRules/Rules.php
index bf671c3bec4f..712200321764 100644
--- a/system/Validation/StrictRules/Rules.php
+++ b/system/Validation/StrictRules/Rules.php
@@ -24,7 +24,7 @@
  */
 class Rules
 {
-    private NonStrictRules $nonStrictRules;
+    private readonly NonStrictRules $nonStrictRules;
 
     public function __construct()
     {
diff --git a/tests/system/Cache/Handlers/FileHandlerTest.php b/tests/system/Cache/Handlers/FileHandlerTest.php
index 0bcaccf817c3..3acb1dbf53c6 100644
--- a/tests/system/Cache/Handlers/FileHandlerTest.php
+++ b/tests/system/Cache/Handlers/FileHandlerTest.php
@@ -377,7 +377,7 @@ public function testGetMetaDataMiss(): void
 final class BaseTestFileHandler extends FileHandler
 {
     private static string $directory = 'FileHandler';
-    private Cache $config;
+    private readonly Cache $config;
 
     public function __construct()
     {
diff --git a/utils/Rector/UnderscoreToCamelCaseVariableNameRector.php b/utils/Rector/UnderscoreToCamelCaseVariableNameRector.php
index 4af0be534e61..388ae9f808b1 100644
--- a/utils/Rector/UnderscoreToCamelCaseVariableNameRector.php
+++ b/utils/Rector/UnderscoreToCamelCaseVariableNameRector.php
@@ -39,7 +39,7 @@ final class UnderscoreToCamelCaseVariableNameRector extends AbstractRector
      */
     private const PARAM_NAME_REGEX = '#(?<paramPrefix>@param\s.*\s+\$)(?<paramName>%s)#ms';
 
-    private ReservedKeywordAnalyzer $reservedKeywordAnalyzer;
+    private readonly ReservedKeywordAnalyzer $reservedKeywordAnalyzer;
     private PhpDocInfoFactory $phpDocInfoFactory;
     private bool $hasChanged = false;
 

From 9590def4430b34f2cfa80fbbb32b73a4de1bb2d2 Mon Sep 17 00:00:00 2001
From: kenjis <kenji.uui@gmail.com>
Date: Sat, 21 Oct 2023 14:23:29 +0900
Subject: [PATCH 14/21] chore: enable
 ClassPropertyAssignToConstructorPromotionRector to the extent that existing
 product codes are not broken

---
 rector.php | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/rector.php b/rector.php
index bcf553e24116..bc6b54cf2883 100644
--- a/rector.php
+++ b/rector.php
@@ -123,7 +123,17 @@
         SimplifyRegexPatternRector::class,
 
         // PHP 8.0 features but cause breaking changes
-        ClassPropertyAssignToConstructorPromotionRector::class,
+        ClassPropertyAssignToConstructorPromotionRector::class => [
+            __DIR__ . '/system/Database/BaseResult.php',
+            __DIR__ . '/system/Database/RawSql.php',
+            __DIR__ . '/system/Debug/BaseExceptionHandler.php',
+            __DIR__ . '/system/Filters/Filters.php',
+            __DIR__ . '/system/HTTP/CURLRequest.php',
+            __DIR__ . '/system/HTTP/DownloadResponse.php',
+            __DIR__ . '/system/HTTP/IncomingRequest.php',
+            __DIR__ . '/system/Security/Security.php',
+            __DIR__ . '/system/Session/Session.php',
+        ],
         MixedTypeRector::class,
 
         // PHP 8.1 features but cause breaking changes

From 4cc43fbd468c5f02449eed9f499a703964064c41 Mon Sep 17 00:00:00 2001
From: kenjis <kenji.uui@gmail.com>
Date: Sat, 21 Oct 2023 15:14:43 +0900
Subject: [PATCH 15/21] refactor: apply
 ClassPropertyAssignToConstructorPromotionRector and manual tweaks

---
 system/Autoloader/FileLocatorCached.php       |  9 +--
 system/Cache/ResponseCache.php                |  9 +--
 .../Utilities/Routes/AutoRouteCollector.php   | 21 ++----
 .../AutoRouterImproved/AutoRouteCollector.php | 53 +++++---------
 .../ControllerMethodReader.php                | 27 +++----
 .../Utilities/Routes/ControllerFinder.php     | 19 ++---
 .../Routes/ControllerMethodReader.php         | 17 ++---
 .../Utilities/Routes/FilterCollector.php      | 18 ++---
 system/HTTP/SiteURIFactory.php                | 11 +--
 system/Router/AutoRouter.php                  | 73 +++++++------------
 system/Router/AutoRouterImproved.php          | 47 ++++--------
 system/Router/DefinedRouteCollector.php       |  8 +-
 ...nderscoreToCamelCaseVariableNameRector.php |  8 +-
 13 files changed, 115 insertions(+), 205 deletions(-)

diff --git a/system/Autoloader/FileLocatorCached.php b/system/Autoloader/FileLocatorCached.php
index 844e06ca818f..2dfe85a38f0b 100644
--- a/system/Autoloader/FileLocatorCached.php
+++ b/system/Autoloader/FileLocatorCached.php
@@ -21,8 +21,6 @@
  */
 final class FileLocatorCached implements FileLocatorInterface
 {
-    private readonly FileLocator $locator;
-
     /**
      * @var CacheInterface|FileVarExportHandler
      */
@@ -49,10 +47,11 @@ final class FileLocatorCached implements FileLocatorInterface
     /**
      * @param CacheInterface|FileVarExportHandler|null $cache
      */
-    public function __construct(FileLocator $locator, $cache = null)
-    {
+    public function __construct(
+        private readonly FileLocator $locator,
+        $cache = null
+    ) {
         $this->cacheHandler = $cache ?? new FileVarExportHandler();
-        $this->locator      = $locator;
 
         $this->loadCache();
     }
diff --git a/system/Cache/ResponseCache.php b/system/Cache/ResponseCache.php
index 83ffdfeca1c3..064b9250b5a6 100644
--- a/system/Cache/ResponseCache.php
+++ b/system/Cache/ResponseCache.php
@@ -47,12 +47,11 @@ final class ResponseCache
      */
     private int $ttl = 0;
 
-    private readonly CacheInterface $cache;
-
-    public function __construct(CacheConfig $config, CacheInterface $cache)
-    {
+    public function __construct(
+        CacheConfig $config,
+        private readonly CacheInterface $cache
+    ) {
         $this->cacheQueryString = $config->cacheQueryString;
-        $this->cache            = $cache;
     }
 
     /**
diff --git a/system/Commands/Utilities/Routes/AutoRouteCollector.php b/system/Commands/Utilities/Routes/AutoRouteCollector.php
index 5455951aa809..ba8d6b588623 100644
--- a/system/Commands/Utilities/Routes/AutoRouteCollector.php
+++ b/system/Commands/Utilities/Routes/AutoRouteCollector.php
@@ -18,22 +18,17 @@
  */
 final class AutoRouteCollector
 {
-    /**
-     * @var string namespace to search
-     */
-    private readonly string $namespace;
-
-    private readonly string $defaultController;
-    private readonly string $defaultMethod;
-
     /**
      * @param string $namespace namespace to search
      */
-    public function __construct(string $namespace, string $defaultController, string $defaultMethod)
-    {
-        $this->namespace         = $namespace;
-        $this->defaultController = $defaultController;
-        $this->defaultMethod     = $defaultMethod;
+    public function __construct(
+        /**
+         * @var string namespace to search
+         */
+        private readonly string $namespace,
+        private readonly string $defaultController,
+        private readonly string $defaultMethod
+    ) {
     }
 
     /**
diff --git a/system/Commands/Utilities/Routes/AutoRouterImproved/AutoRouteCollector.php b/system/Commands/Utilities/Routes/AutoRouterImproved/AutoRouteCollector.php
index e7fe0871e034..2075dbef8ac8 100644
--- a/system/Commands/Utilities/Routes/AutoRouterImproved/AutoRouteCollector.php
+++ b/system/Commands/Utilities/Routes/AutoRouterImproved/AutoRouteCollector.php
@@ -21,44 +21,25 @@
  */
 final class AutoRouteCollector
 {
-    /**
-     * @var string namespace to search
-     */
-    private readonly string $namespace;
-
-    private readonly string $defaultController;
-    private readonly string $defaultMethod;
-    private readonly array $httpMethods;
-
-    /**
-     * List of controllers in Defined Routes that should not be accessed via Auto-Routing.
-     *
-     * @var class-string[]
-     */
-    private readonly array $protectedControllers;
-
-    /**
-     * @var string URI prefix for Module Routing
-     */
-    private string $prefix;
-
-    /**
-     * @param string $namespace namespace to search
-     */
     public function __construct(
-        string $namespace,
-        string $defaultController,
-        string $defaultMethod,
-        array $httpMethods,
-        array $protectedControllers,
-        string $prefix = ''
+        /**
+         * @var string namespace to search
+         */
+        private readonly string $namespace,
+        private readonly string $defaultController,
+        private readonly string $defaultMethod,
+        private readonly array $httpMethods,
+        /**
+         * List of controllers in Defined Routes that should not be accessed via Auto-Routing.
+         *
+         * @var class-string[]
+         */
+        private readonly array $protectedControllers,
+        /**
+         * @var string URI prefix for Module Routing
+         */
+        private string $prefix = ''
     ) {
-        $this->namespace            = $namespace;
-        $this->defaultController    = $defaultController;
-        $this->defaultMethod        = $defaultMethod;
-        $this->httpMethods          = $httpMethods;
-        $this->protectedControllers = $protectedControllers;
-        $this->prefix               = $prefix;
     }
 
     /**
diff --git a/system/Commands/Utilities/Routes/AutoRouterImproved/ControllerMethodReader.php b/system/Commands/Utilities/Routes/AutoRouterImproved/ControllerMethodReader.php
index 6e982d4612d3..d1c1c5a40ee5 100644
--- a/system/Commands/Utilities/Routes/AutoRouterImproved/ControllerMethodReader.php
+++ b/system/Commands/Utilities/Routes/AutoRouterImproved/ControllerMethodReader.php
@@ -21,23 +21,16 @@
  */
 final class ControllerMethodReader
 {
-    /**
-     * @var string the default namespace
-     */
-    private readonly string $namespace;
-
-    /**
-     * @var list<string>
-     */
-    private readonly array $httpMethods;
-
-    /**
-     * @param string $namespace the default namespace
-     */
-    public function __construct(string $namespace, array $httpMethods)
-    {
-        $this->namespace   = $namespace;
-        $this->httpMethods = $httpMethods;
+    public function __construct(
+        /**
+         * @var string $namespace the default namespace
+         */
+        private readonly string $namespace,
+        /**
+         * list<string>
+         */
+        private readonly array $httpMethods
+    ) {
     }
 
     /**
diff --git a/system/Commands/Utilities/Routes/ControllerFinder.php b/system/Commands/Utilities/Routes/ControllerFinder.php
index e9bce1260c46..79743a267b25 100644
--- a/system/Commands/Utilities/Routes/ControllerFinder.php
+++ b/system/Commands/Utilities/Routes/ControllerFinder.php
@@ -21,20 +21,15 @@
  */
 final class ControllerFinder
 {
-    /**
-     * @var string namespace to search
-     */
-    private readonly string $namespace;
-
     private readonly FileLocatorInterface $locator;
 
-    /**
-     * @param string $namespace namespace to search
-     */
-    public function __construct(string $namespace)
-    {
-        $this->namespace = $namespace;
-        $this->locator   = Services::locator();
+    public function __construct(
+        /**
+         * @var string namespace to search
+         */
+        private readonly string $namespace
+    ) {
+        $this->locator = Services::locator();
     }
 
     /**
diff --git a/system/Commands/Utilities/Routes/ControllerMethodReader.php b/system/Commands/Utilities/Routes/ControllerMethodReader.php
index f281a2267640..4d3b7c93c924 100644
--- a/system/Commands/Utilities/Routes/ControllerMethodReader.php
+++ b/system/Commands/Utilities/Routes/ControllerMethodReader.php
@@ -21,17 +21,12 @@
  */
 final class ControllerMethodReader
 {
-    /**
-     * @var string the default namespace
-     */
-    private readonly string $namespace;
-
-    /**
-     * @param string $namespace the default namespace
-     */
-    public function __construct(string $namespace)
-    {
-        $this->namespace = $namespace;
+    public function __construct(
+        /**
+         * @var string $namespace the default namespace
+         */
+        private readonly string $namespace
+    ) {
     }
 
     /**
diff --git a/system/Commands/Utilities/Routes/FilterCollector.php b/system/Commands/Utilities/Routes/FilterCollector.php
index 0924f08d230b..3ad6cec41ac4 100644
--- a/system/Commands/Utilities/Routes/FilterCollector.php
+++ b/system/Commands/Utilities/Routes/FilterCollector.php
@@ -24,16 +24,14 @@
  */
 final class FilterCollector
 {
-    /**
-     * Whether to reset Defined Routes.
-     *
-     * If set to true, route filters are not found.
-     */
-    private readonly bool $resetRoutes;
-
-    public function __construct(bool $resetRoutes = false)
-    {
-        $this->resetRoutes = $resetRoutes;
+    public function __construct(
+        /**
+         * Whether to reset Defined Routes.
+         *
+         * If set to true, route filters are not found.
+         */
+        private readonly bool $resetRoutes = false
+    ) {
     }
 
     /**
diff --git a/system/HTTP/SiteURIFactory.php b/system/HTTP/SiteURIFactory.php
index de1069f6a617..d1391baf597f 100644
--- a/system/HTTP/SiteURIFactory.php
+++ b/system/HTTP/SiteURIFactory.php
@@ -24,13 +24,10 @@
  */
 final class SiteURIFactory
 {
-    private readonly App $appConfig;
-    private readonly Superglobals $superglobals;
-
-    public function __construct(App $appConfig, Superglobals $superglobals)
-    {
-        $this->appConfig    = $appConfig;
-        $this->superglobals = $superglobals;
+    public function __construct(
+        private readonly App $appConfig,
+        private readonly Superglobals $superglobals
+    ) {
     }
 
     /**
diff --git a/system/Router/AutoRouter.php b/system/Router/AutoRouter.php
index 4a46275f6227..78bfab744587 100644
--- a/system/Router/AutoRouter.php
+++ b/system/Router/AutoRouter.php
@@ -19,60 +19,41 @@
  */
 final class AutoRouter implements AutoRouterInterface
 {
-    /**
-     * List of CLI routes that do not contain '*' routes.
-     *
-     * @var array<string, Closure|string> [routeKey => handler]
-     */
-    private readonly array $cliRoutes;
-
     /**
      * Sub-directory that contains the requested controller class.
      * Primarily used by 'autoRoute'.
      */
     private ?string $directory = null;
 
-    /**
-     * The name of the controller class.
-     */
-    private string $controller;
-
-    /**
-     * The name of the method to use.
-     */
-    private string $method;
-
-    /**
-     * Whether dashes in URI's should be converted
-     * to underscores when determining method names.
-     */
-    private bool $translateURIDashes;
-
-    /**
-     * HTTP verb for the request.
-     */
-    private readonly string $httpVerb;
-
-    /**
-     * Default namespace for controllers.
-     */
-    private readonly string $defaultNamespace;
-
     public function __construct(
-        array $cliRoutes,
-        string $defaultNamespace,
-        string $defaultController,
-        string $defaultMethod,
-        bool $translateURIDashes,
-        string $httpVerb
+        /**
+         * List of CLI routes that do not contain '*' routes.
+         *
+         * @var array<string, Closure|string> [routeKey => handler]
+         */
+        private readonly array $cliRoutes,
+        /**
+         * Default namespace for controllers.
+         */
+        private readonly string $defaultNamespace,
+        /**
+         * The name of the controller class.
+         */
+        private string $controller,
+        /**
+         * The name of the method to use.
+         */
+        private string $method,
+        /**
+         * Whether dashes in URI's should be converted
+         * to underscores when determining method names.
+         */
+        private bool $translateURIDashes,
+        /**
+         * HTTP verb for the request.
+         */
+        private readonly string $httpVerb
     ) {
-        $this->cliRoutes          = $cliRoutes;
-        $this->defaultNamespace   = $defaultNamespace;
-        $this->translateURIDashes = $translateURIDashes;
-        $this->httpVerb           = $httpVerb;
-
-        $this->controller = $defaultController;
-        $this->method     = $defaultMethod;
     }
 
     /**
diff --git a/system/Router/AutoRouterImproved.php b/system/Router/AutoRouterImproved.php
index 24122105b097..3c8da69e05f5 100644
--- a/system/Router/AutoRouterImproved.php
+++ b/system/Router/AutoRouterImproved.php
@@ -24,13 +24,6 @@
  */
 final class AutoRouterImproved implements AutoRouterInterface
 {
-    /**
-     * List of controllers in Defined Routes that should not be accessed via this Auto-Routing.
-     *
-     * @var class-string[]
-     */
-    private readonly array $protectedControllers;
-
     /**
      * Sub-directory that contains the requested controller class.
      */
@@ -53,27 +46,11 @@ final class AutoRouterImproved implements AutoRouterInterface
      */
     private array $params = [];
 
-    /**
-     * Whether dashes in URI's should be converted
-     * to underscores when determining method names.
-     */
-    private readonly bool $translateURIDashes;
-
     /**
      * The namespace for controllers.
      */
     private string $namespace;
 
-    /**
-     * The name of the default controller class.
-     */
-    private readonly string $defaultController;
-
-    /**
-     * The name of the default method without HTTP verb prefix.
-     */
-    private readonly string $defaultMethod;
-
     /**
      * The URI segments.
      *
@@ -106,18 +83,24 @@ final class AutoRouterImproved implements AutoRouterInterface
      * @deprecated $httpVerb is deprecated. No longer used.
      */
     public function __construct(// @phpstan-ignore-line
-        array $protectedControllers,
+        /**
+         * List of controllers in Defined Routes that should not be accessed via this Auto-Routing.
+         */
+        private readonly array $protectedControllers,
         string $namespace,
-        string $defaultController,
-        string $defaultMethod,
-        bool $translateURIDashes,
+        private readonly string $defaultController,
+        /**
+         * The name of the default method without HTTP verb prefix.
+         */
+        private readonly string $defaultMethod,
+        /**
+         * Whether dashes in URI's should be converted
+         * to underscores when determining method names.
+         */
+        private readonly bool $translateURIDashes,
         string $httpVerb
     ) {
-        $this->protectedControllers = $protectedControllers;
-        $this->namespace            = rtrim($namespace, '\\');
-        $this->translateURIDashes   = $translateURIDashes;
-        $this->defaultController    = $defaultController;
-        $this->defaultMethod        = $defaultMethod;
+        $this->namespace = rtrim($namespace, '\\');
 
         // Set the default values
         $this->controller = $this->defaultController;
diff --git a/system/Router/DefinedRouteCollector.php b/system/Router/DefinedRouteCollector.php
index c8f0a93323e9..7fff8cfaac1f 100644
--- a/system/Router/DefinedRouteCollector.php
+++ b/system/Router/DefinedRouteCollector.php
@@ -21,11 +21,9 @@
  */
 final class DefinedRouteCollector
 {
-    private readonly RouteCollection $routeCollection;
-
-    public function __construct(RouteCollection $routes)
-    {
-        $this->routeCollection = $routes;
+    public function __construct(
+        private readonly RouteCollection $routeCollection
+    ) {
     }
 
     /**
diff --git a/utils/Rector/UnderscoreToCamelCaseVariableNameRector.php b/utils/Rector/UnderscoreToCamelCaseVariableNameRector.php
index 388ae9f808b1..958b61868d7d 100644
--- a/utils/Rector/UnderscoreToCamelCaseVariableNameRector.php
+++ b/utils/Rector/UnderscoreToCamelCaseVariableNameRector.php
@@ -39,16 +39,12 @@ final class UnderscoreToCamelCaseVariableNameRector extends AbstractRector
      */
     private const PARAM_NAME_REGEX = '#(?<paramPrefix>@param\s.*\s+\$)(?<paramName>%s)#ms';
 
-    private readonly ReservedKeywordAnalyzer $reservedKeywordAnalyzer;
-    private PhpDocInfoFactory $phpDocInfoFactory;
     private bool $hasChanged = false;
 
     public function __construct(
-        ReservedKeywordAnalyzer $reservedKeywordAnalyzer,
-        PhpDocInfoFactory $phpDocInfoFactory
+        private readonly ReservedKeywordAnalyzer $reservedKeywordAnalyzer,
+        private PhpDocInfoFactory $phpDocInfoFactory
     ) {
-        $this->reservedKeywordAnalyzer = $reservedKeywordAnalyzer;
-        $this->phpDocInfoFactory       = $phpDocInfoFactory;
     }
 
     public function getRuleDefinition(): RuleDefinition

From 942a6e8b17054f29b6d23c5e638e4964663bf034 Mon Sep 17 00:00:00 2001
From: kenjis <kenji.uui@gmail.com>
Date: Sat, 21 Oct 2023 15:28:42 +0900
Subject: [PATCH 16/21] docs: fix @var type to fix PHPStan error

---
 system/Router/AutoRouter.php | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/system/Router/AutoRouter.php b/system/Router/AutoRouter.php
index 78bfab744587..325eab77fdd8 100644
--- a/system/Router/AutoRouter.php
+++ b/system/Router/AutoRouter.php
@@ -13,6 +13,7 @@
 
 use Closure;
 use CodeIgniter\Exceptions\PageNotFoundException;
+use CodeIgniter\HTTP\ResponseInterface;
 
 /**
  * Router for Auto-Routing
@@ -29,7 +30,7 @@ public function __construct(
         /**
          * List of CLI routes that do not contain '*' routes.
          *
-         * @var array<string, Closure|string> [routeKey => handler]
+         * @var array<string, Closure(): (ResponseInterface|string|void)|string> [routeKey => handler]
          */
         private readonly array $cliRoutes,
         /**

From 2c4364afb18d04f59c400bc70054e4715ce3d64b Mon Sep 17 00:00:00 2001
From: kenjis <kenji.uui@gmail.com>
Date: Sat, 21 Oct 2023 15:28:51 +0900
Subject: [PATCH 17/21] chore: remove ignoreErrors

---
 phpstan-baseline.php | 5 -----
 1 file changed, 5 deletions(-)

diff --git a/phpstan-baseline.php b/phpstan-baseline.php
index 979935aa8e2d..3a5500a4ce28 100644
--- a/phpstan-baseline.php
+++ b/phpstan-baseline.php
@@ -2641,11 +2641,6 @@
 	'count' => 1,
 	'path' => __DIR__ . '/system/Router/AutoRouter.php',
 ];
-$ignoreErrors[] = [
-	'message' => '#^Property CodeIgniter\\\\Router\\\\AutoRouter\\:\\:\\$cliRoutes type has no signature specified for Closure\\.$#',
-	'count' => 1,
-	'path' => __DIR__ . '/system/Router/AutoRouter.php',
-];
 $ignoreErrors[] = [
 	'message' => '#^Short ternary operator is not allowed\\. Use null coalesce operator if applicable or consider using long ternary\\.$#',
 	'count' => 1,

From 5d99f3d4202c2d72c386aa206a4258b840411217 Mon Sep 17 00:00:00 2001
From: kenjis <kenji.uui@gmail.com>
Date: Mon, 23 Oct 2023 08:57:19 +0900
Subject: [PATCH 18/21] refactor: run rector

---
 system/Config/Factories.php | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/system/Config/Factories.php b/system/Config/Factories.php
index f2a59522af73..72c561e43415 100644
--- a/system/Config/Factories.php
+++ b/system/Config/Factories.php
@@ -36,7 +36,7 @@ final class Factories
      *
      * @var array<string, array<string, bool|string|null>>
      */
-    private static $options = [];
+    private static array $options = [];
 
     /**
      * Explicit options for the Config
@@ -64,7 +64,7 @@ final class Factories
      *
      * @var array<string, array<string, class-string>>
      */
-    private static $aliases = [];
+    private static array $aliases = [];
 
     /**
      * Store for instances of any component that
@@ -77,7 +77,7 @@ final class Factories
      *
      * @var array<string, array<class-string, object>>
      */
-    private static $instances = [];
+    private static array $instances = [];
 
     /**
      * Whether the component instances are updated?
@@ -86,7 +86,7 @@ final class Factories
      *
      * @internal For caching only
      */
-    private static $updated = [];
+    private static array $updated = [];
 
     /**
      * Define the class to load. You can *override* the concrete class.

From 9f2785facfedfe3c91309eb38e2f3fd1bab9410f Mon Sep 17 00:00:00 2001
From: kenjis <kenji.uui@gmail.com>
Date: Mon, 30 Oct 2023 10:49:41 +0900
Subject: [PATCH 19/21] refactor: run rector

---
 system/CLI/Console.php                               |  2 +-
 system/Cache/Handlers/MemcachedHandler.php           |  2 +-
 system/Cache/Handlers/PredisHandler.php              |  2 +-
 system/Cache/Handlers/RedisHandler.php               |  2 +-
 system/Commands/Generators/CellGenerator.php         |  2 +-
 system/Commands/Generators/ModelGenerator.php        |  2 +-
 system/Commands/Translation/LocalizationFinder.php   |  4 ++--
 system/Config/BaseConfig.php                         |  2 +-
 system/Config/BaseService.php                        |  2 +-
 system/Database/Forge.php                            |  2 +-
 system/Database/Postgre/Builder.php                  |  2 +-
 system/Database/SQLite3/Table.php                    |  2 +-
 system/Debug/Toolbar.php                             |  2 +-
 system/Email/Email.php                               |  2 +-
 system/Events/Events.php                             |  2 +-
 system/Helpers/array_helper.php                      |  2 +-
 system/Images/Handlers/BaseHandler.php               |  2 +-
 system/Router/RouteCollection.php                    |  6 +++---
 system/Session/Session.php                           |  4 ++--
 system/View/Cells/Cell.php                           |  2 +-
 system/View/Table.php                                |  2 +-
 tests/system/API/ResponseTraitTest.php               |  2 +-
 tests/system/HTTP/IncomingRequestTest.php            |  4 ++--
 tests/system/Helpers/FilesystemHelperTest.php        | 12 ++----------
 tests/system/Router/DefinedRouteCollectorTest.php    |  2 +-
 .../Router/RouteCollectionReverseRouteTest.php       |  2 +-
 tests/system/Router/RouteCollectionTest.php          |  2 +-
 27 files changed, 33 insertions(+), 41 deletions(-)

diff --git a/system/CLI/Console.php b/system/CLI/Console.php
index adcf9aaeca8b..3e7b8a767a82 100644
--- a/system/CLI/Console.php
+++ b/system/CLI/Console.php
@@ -39,7 +39,7 @@ public function run()
         Services::routes()->loadRoutes();
 
         $runner  = Services::commands();
-        $params  = array_merge(CLI::getSegments(), CLI::getOptions());
+        $params  = [...CLI::getSegments(), ...CLI::getOptions()];
         $params  = $this->parseParamsForHelpOption($params);
         $command = array_shift($params) ?? 'list';
 
diff --git a/system/Cache/Handlers/MemcachedHandler.php b/system/Cache/Handlers/MemcachedHandler.php
index e8658906392a..c89ecd10e595 100644
--- a/system/Cache/Handlers/MemcachedHandler.php
+++ b/system/Cache/Handlers/MemcachedHandler.php
@@ -51,7 +51,7 @@ public function __construct(Cache $config)
     {
         $this->prefix = $config->prefix;
 
-        $this->config = array_merge($this->config, $config->memcached);
+        $this->config = [...$this->config, ...$config->memcached];
     }
 
     /**
diff --git a/system/Cache/Handlers/PredisHandler.php b/system/Cache/Handlers/PredisHandler.php
index cdebd7487d8a..ca4e9f9d0465 100644
--- a/system/Cache/Handlers/PredisHandler.php
+++ b/system/Cache/Handlers/PredisHandler.php
@@ -53,7 +53,7 @@ public function __construct(Cache $config)
         $this->prefix = $config->prefix;
 
         if (isset($config->redis)) {
-            $this->config = array_merge($this->config, $config->redis);
+            $this->config = [...$this->config, ...$config->redis];
         }
     }
 
diff --git a/system/Cache/Handlers/RedisHandler.php b/system/Cache/Handlers/RedisHandler.php
index 05957cb4e0cf..d4d6097ff527 100644
--- a/system/Cache/Handlers/RedisHandler.php
+++ b/system/Cache/Handlers/RedisHandler.php
@@ -51,7 +51,7 @@ public function __construct(Cache $config)
     {
         $this->prefix = $config->prefix;
 
-        $this->config = array_merge($this->config, $config->redis);
+        $this->config = [...$this->config, ...$config->redis];
     }
 
     /**
diff --git a/system/Commands/Generators/CellGenerator.php b/system/Commands/Generators/CellGenerator.php
index 3d31231697fe..a6305e9fa30d 100644
--- a/system/Commands/Generators/CellGenerator.php
+++ b/system/Commands/Generators/CellGenerator.php
@@ -77,7 +77,7 @@ public function run(array $params)
         $this->component = 'Cell';
         $this->directory = 'Cells';
 
-        $params = array_merge($params, ['suffix' => null]);
+        $params = [...$params, 'suffix' => null];
 
         $this->templatePath  = config(Generators::class)->views[$this->name]['class'];
         $this->template      = 'cell.tpl.php';
diff --git a/system/Commands/Generators/ModelGenerator.php b/system/Commands/Generators/ModelGenerator.php
index 6a817ef50eb5..9179339d002c 100644
--- a/system/Commands/Generators/ModelGenerator.php
+++ b/system/Commands/Generators/ModelGenerator.php
@@ -123,7 +123,7 @@ protected function prepare(string $class): string
             }
 
             $return = '\\' . trim($return, '\\') . '::class';
-            $this->call('make:entity', array_merge([$baseClass], $this->params));
+            $this->call('make:entity', [$baseClass, ...$this->params]);
         } else {
             $return = "'{$return}'";
         }
diff --git a/system/Commands/Translation/LocalizationFinder.php b/system/Commands/Translation/LocalizationFinder.php
index d8fbbf1aad50..33f4e2571a2c 100644
--- a/system/Commands/Translation/LocalizationFinder.php
+++ b/system/Commands/Translation/LocalizationFinder.php
@@ -130,7 +130,7 @@ private function process(string $currentDir, string $currentLocale): void
             $countNewKeys += ArrayHelper::recursiveCount($languageDiff);
 
             if ($this->showNew) {
-                $tableRows = array_merge($this->arrayToTableRows($langFileName, $languageDiff), $tableRows);
+                $tableRows = [...$this->arrayToTableRows($langFileName, $languageDiff), ...$tableRows];
             } else {
                 $newLanguageKeys = array_replace_recursive($foundLanguageKeys[$langFileName], $languageStoredKeys);
 
@@ -303,7 +303,7 @@ private function arrayToTableRows(string $langFileName, array $array): array
 
         foreach ($array as $value) {
             if (is_array($value)) {
-                $rows = array_merge($rows, $this->arrayToTableRows($langFileName, $value));
+                $rows = [...$rows, ...$this->arrayToTableRows($langFileName, $value)];
 
                 continue;
             }
diff --git a/system/Config/BaseConfig.php b/system/Config/BaseConfig.php
index a796438ca0cb..fbe50e1c48fc 100644
--- a/system/Config/BaseConfig.php
+++ b/system/Config/BaseConfig.php
@@ -261,7 +261,7 @@ protected function registerProperties()
 
             foreach ($properties as $property => $value) {
                 if (isset($this->{$property}) && is_array($this->{$property}) && is_array($value)) {
-                    $this->{$property} = array_merge($this->{$property}, $value);
+                    $this->{$property} = [...$this->{$property}, ...$value];
                 } else {
                     $this->{$property} = $value;
                 }
diff --git a/system/Config/BaseService.php b/system/Config/BaseService.php
index 970977dd416a..d07889b2d41c 100644
--- a/system/Config/BaseService.php
+++ b/system/Config/BaseService.php
@@ -266,7 +266,7 @@ public static function __callStatic(string $name, array $arguments)
     public static function serviceExists(string $name): ?string
     {
         static::buildServicesCache();
-        $services = array_merge(self::$serviceNames, [Services::class]);
+        $services = [...self::$serviceNames, Services::class];
         $name     = strtolower($name);
 
         foreach ($services as $service) {
diff --git a/system/Database/Forge.php b/system/Database/Forge.php
index cb0e21c64911..f7161d752cbb 100644
--- a/system/Database/Forge.php
+++ b/system/Database/Forge.php
@@ -1094,7 +1094,7 @@ public function processIndexes(string $table): bool
         $this->fields      = $fields;
 
         if ($this->foreignKeys !== []) {
-            $sqls = array_merge($sqls, $this->_processForeignKeys($table, true));
+            $sqls = [...$sqls, ...$this->_processForeignKeys($table, true)];
         }
 
         foreach ($sqls as $sql) {
diff --git a/system/Database/Postgre/Builder.php b/system/Database/Postgre/Builder.php
index e9763089a90f..8fda3a640402 100644
--- a/system/Database/Postgre/Builder.php
+++ b/system/Database/Postgre/Builder.php
@@ -306,7 +306,7 @@ protected function _like_statement(?string $prefix, string $column, ?string $not
     public function join(string $table, $cond, string $type = '', ?bool $escape = null)
     {
         if (! in_array('FULL OUTER', $this->joinTypes, true)) {
-            $this->joinTypes = array_merge($this->joinTypes, ['FULL OUTER']);
+            $this->joinTypes = [...$this->joinTypes, 'FULL OUTER'];
         }
 
         return parent::join($table, $cond, $type, $escape);
diff --git a/system/Database/SQLite3/Table.php b/system/Database/SQLite3/Table.php
index 9d3d1034119c..244bc20e1622 100644
--- a/system/Database/SQLite3/Table.php
+++ b/system/Database/SQLite3/Table.php
@@ -271,7 +271,7 @@ public function addForeignKey(array $foreignKeys)
             $fk[] = $obj;
         }
 
-        $this->foreignKeys = array_merge($this->foreignKeys, $fk);
+        $this->foreignKeys = [...$this->foreignKeys, ...$fk];
 
         return $this;
     }
diff --git a/system/Debug/Toolbar.php b/system/Debug/Toolbar.php
index 3cf0566cca07..ff878785ccd2 100644
--- a/system/Debug/Toolbar.php
+++ b/system/Debug/Toolbar.php
@@ -326,7 +326,7 @@ protected function structureTimelineData(array $elements): array
         }
 
         // Make sure our younger siblings know their relatives, too
-        return array_merge([$element], $this->structureTimelineData($elements));
+        return [$element, ...$this->structureTimelineData($elements)];
     }
 
     /**
diff --git a/system/Email/Email.php b/system/Email/Email.php
index 649e1188f35e..c3d56033b6d1 100644
--- a/system/Email/Email.php
+++ b/system/Email/Email.php
@@ -2249,7 +2249,7 @@ protected static function substr($str, $start, $length = null)
     protected function setArchiveValues(): array
     {
         // Get property values and add anything prepped in tmpArchive
-        $this->archive = array_merge(get_object_vars($this), $this->tmpArchive);
+        $this->archive = [...get_object_vars($this), ...$this->tmpArchive];
         unset($this->archive['archive']);
 
         // Clear tmpArchive for next run
diff --git a/system/Events/Events.php b/system/Events/Events.php
index b240dc29e1ca..fa10e8b4be14 100644
--- a/system/Events/Events.php
+++ b/system/Events/Events.php
@@ -91,7 +91,7 @@ public static function initialize()
             return false; // @codeCoverageIgnore
         }, $files));
 
-        static::$files = array_unique(array_merge($files, [$events]));
+        static::$files = array_unique([...$files, $events]);
 
         foreach (static::$files as $file) {
             include $file;
diff --git a/system/Helpers/array_helper.php b/system/Helpers/array_helper.php
index 6d501e273202..d11789a3e63a 100644
--- a/system/Helpers/array_helper.php
+++ b/system/Helpers/array_helper.php
@@ -136,7 +136,7 @@ function array_flatten_with_dots(iterable $array, string $id = ''): array
             $newKey = $id . $key;
 
             if (is_array($value) && $value !== []) {
-                $flattened = array_merge($flattened, array_flatten_with_dots($value, $newKey . '.'));
+                $flattened = [...$flattened, ...array_flatten_with_dots($value, $newKey . '.')];
             } else {
                 $flattened[$newKey] = $value;
             }
diff --git a/system/Images/Handlers/BaseHandler.php b/system/Images/Handlers/BaseHandler.php
index 10884805aae5..ade0d5a455f6 100644
--- a/system/Images/Handlers/BaseHandler.php
+++ b/system/Images/Handlers/BaseHandler.php
@@ -413,7 +413,7 @@ abstract protected function _flip(string $direction);
      */
     public function text(string $text, array $options = [])
     {
-        $options                = array_merge($this->textDefaults, $options);
+        $options                = [...$this->textDefaults, ...$options];
         $options['color']       = trim($options['color'], '# ');
         $options['shadowColor'] = trim($options['shadowColor'], '# ');
 
diff --git a/system/Router/RouteCollection.php b/system/Router/RouteCollection.php
index ea434001cb46..5434322f2ccf 100644
--- a/system/Router/RouteCollection.php
+++ b/system/Router/RouteCollection.php
@@ -390,7 +390,7 @@ public function addPlaceholder($placeholder, ?string $pattern = null): RouteColl
             $placeholder = [$placeholder => $pattern];
         }
 
-        $this->placeholders = array_merge($this->placeholders, $placeholder);
+        $this->placeholders = [...$this->placeholders, ...$placeholder];
 
         return $this;
     }
@@ -783,7 +783,7 @@ public function group(string $name, ...$params)
             if (isset($options['filter'])) {
                 // Merge filters.
                 $currentFilter     = (array) ($this->currentOptions['filter'] ?? []);
-                $options['filter'] = array_merge($currentFilter, (array) $options['filter']);
+                $options['filter'] = [...$currentFilter, ...(array) $options['filter']];
             }
 
             // Merge options other than filters.
@@ -1147,7 +1147,7 @@ public function view(string $from, string $view, ?array $options = null): RouteC
             ->render($view, $options);
 
         $routeOptions = $options ?? [];
-        $routeOptions = array_merge($routeOptions, ['view' => $view]);
+        $routeOptions = [...$routeOptions, 'view' => $view];
 
         $this->create(Method::GET, $from, $to, $routeOptions);
 
diff --git a/system/Session/Session.php b/system/Session/Session.php
index 4e4a01581ba2..45f6e4090f32 100644
--- a/system/Session/Session.php
+++ b/system/Session/Session.php
@@ -505,7 +505,7 @@ public function get(?string $key = null)
         }
 
         $userdata = [];
-        $_exclude = array_merge(['__ci_vars'], $this->getFlashKeys(), $this->getTempKeys());
+        $_exclude = ['__ci_vars', ...$this->getFlashKeys(), ...$this->getTempKeys()];
 
         $keys = array_keys($_SESSION);
 
@@ -537,7 +537,7 @@ public function has(string $key): bool
     public function push(string $key, array $data)
     {
         if ($this->has($key) && is_array($value = $this->get($key))) {
-            $this->set($key, array_merge($value, $data));
+            $this->set($key, [...$value, ...$data]);
         }
     }
 
diff --git a/system/View/Cells/Cell.php b/system/View/Cells/Cell.php
index b8c43e173b45..cde49dcbd558 100644
--- a/system/View/Cells/Cell.php
+++ b/system/View/Cells/Cell.php
@@ -75,7 +75,7 @@ final protected function view(?string $view, array $data = []): string
     {
         $properties = $this->getPublicProperties();
         $properties = $this->includeComputedProperties($properties);
-        $properties = array_merge($properties, $data);
+        $properties = [...$properties, ...$data];
 
         $view = (string) $view;
 
diff --git a/system/View/Table.php b/system/View/Table.php
index 5e241f11fefc..70afca11e219 100644
--- a/system/View/Table.php
+++ b/system/View/Table.php
@@ -228,7 +228,7 @@ public function addRow()
             $tmpRow = array_filter($tmpRow, static fn ($k) => array_key_exists($k, $keyIndex), ARRAY_FILTER_USE_KEY);
 
             // add missing keys to row, but use $this->emptyCells
-            $tmpRow = array_merge($tmpRow, array_map(fn ($v) => ['data' => $this->emptyCells], $missingKeys));
+            $tmpRow = [...$tmpRow, ...array_map(fn ($v) => ['data' => $this->emptyCells], $missingKeys)];
 
             // order keys by $keyIndex values
             uksort($tmpRow, static fn ($k1, $k2) => $keyIndex[$k1] <=> $keyIndex[$k2]);
diff --git a/tests/system/API/ResponseTraitTest.php b/tests/system/API/ResponseTraitTest.php
index 708235e9fbd9..b970d4a8319c 100644
--- a/tests/system/API/ResponseTraitTest.php
+++ b/tests/system/API/ResponseTraitTest.php
@@ -81,7 +81,7 @@ protected function makeController(array $userConfig = [], string $routePath = ''
         $headers = [
             'Accept' => 'text/html',
         ];
-        $headers = array_merge($headers, $userHeaders);
+        $headers = [...$headers, ...$userHeaders];
 
         foreach ($headers as $key => $value) {
             $this->request->setHeader($key, $value);
diff --git a/tests/system/HTTP/IncomingRequestTest.php b/tests/system/HTTP/IncomingRequestTest.php
index dc537093632e..1233ad5a7ebf 100644
--- a/tests/system/HTTP/IncomingRequestTest.php
+++ b/tests/system/HTTP/IncomingRequestTest.php
@@ -870,8 +870,8 @@ public function testGetPostSecondStreams(): void
     {
         $_GET['get']   = '3';
         $_POST['post'] = '5';
-        $this->assertSame(array_merge($_GET, $_POST), $this->request->getPostGet());
-        $this->assertSame(array_merge($_POST, $_GET), $this->request->getGetPost());
+        $this->assertSame([...$_GET, ...$_POST], $this->request->getPostGet());
+        $this->assertSame([...$_POST, ...$_GET], $this->request->getGetPost());
     }
 
     public function testGetBodyWithFalseBody(): void
diff --git a/tests/system/Helpers/FilesystemHelperTest.php b/tests/system/Helpers/FilesystemHelperTest.php
index af682c459f23..3fec67a46498 100644
--- a/tests/system/Helpers/FilesystemHelperTest.php
+++ b/tests/system/Helpers/FilesystemHelperTest.php
@@ -243,11 +243,7 @@ public function testDeleteFilesHandlesRecursion(): void
 
     public function testDeleteFilesLeavesHTFiles(): void
     {
-        $structure = array_merge($this->structure, [
-            '.htaccess'  => 'Deny All',
-            'index.html' => 'foo',
-            'index.php'  => 'blah',
-        ]);
+        $structure = [...$this->structure, '.htaccess' => 'Deny All', 'index.html' => 'foo', 'index.php' => 'blah'];
 
         $vfs = vfsStream::setup('root', null, $structure);
 
@@ -265,11 +261,7 @@ public function testDeleteFilesLeavesHTFiles(): void
 
     public function testDeleteFilesIncludingHidden(): void
     {
-        $structure = array_merge($this->structure, [
-            '.htaccess'  => 'Deny All',
-            'index.html' => 'foo',
-            'index.php'  => 'blah',
-        ]);
+        $structure = [...$this->structure, '.htaccess' => 'Deny All', 'index.html' => 'foo', 'index.php' => 'blah'];
 
         $vfs = vfsStream::setup('root', null, $structure);
 
diff --git a/tests/system/Router/DefinedRouteCollectorTest.php b/tests/system/Router/DefinedRouteCollectorTest.php
index 264c7158b152..3b300ed0afae 100644
--- a/tests/system/Router/DefinedRouteCollectorTest.php
+++ b/tests/system/Router/DefinedRouteCollectorTest.php
@@ -30,7 +30,7 @@ private function createRouteCollection(array $config = [], $moduleConfig = null)
             'Config' => APPPATH . 'Config',
             'App'    => APPPATH,
         ];
-        $config = array_merge($config, $defaults);
+        $config = [...$config, ...$defaults];
 
         Services::autoloader()->addNamespace($config);
 
diff --git a/tests/system/Router/RouteCollectionReverseRouteTest.php b/tests/system/Router/RouteCollectionReverseRouteTest.php
index b318e4036a60..5e7b0c32ea8a 100644
--- a/tests/system/Router/RouteCollectionReverseRouteTest.php
+++ b/tests/system/Router/RouteCollectionReverseRouteTest.php
@@ -39,7 +39,7 @@ protected function getCollector(array $config = [], array $files = [], $moduleCo
             'Config' => APPPATH . 'Config',
             'App'    => APPPATH,
         ];
-        $config = array_merge($config, $defaults);
+        $config = [...$config, ...$defaults];
 
         Services::autoloader()->addNamespace($config);
 
diff --git a/tests/system/Router/RouteCollectionTest.php b/tests/system/Router/RouteCollectionTest.php
index 76eb7fd04fb7..3ad1c8b72aec 100644
--- a/tests/system/Router/RouteCollectionTest.php
+++ b/tests/system/Router/RouteCollectionTest.php
@@ -42,7 +42,7 @@ protected function getCollector(array $config = [], array $files = [], $moduleCo
             'Config' => APPPATH . 'Config',
             'App'    => APPPATH,
         ];
-        $config = array_merge($config, $defaults);
+        $config = [...$config, ...$defaults];
 
         Services::autoloader()->addNamespace($config);
 

From d6f977cadc7ac8c9b358c4067913cab1ff05d892 Mon Sep 17 00:00:00 2001
From: kenjis <kenji.uui@gmail.com>
Date: Tue, 14 Nov 2023 14:15:17 +0900
Subject: [PATCH 20/21] fix: add missing readonly

---
 utils/Rector/UnderscoreToCamelCaseVariableNameRector.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/utils/Rector/UnderscoreToCamelCaseVariableNameRector.php b/utils/Rector/UnderscoreToCamelCaseVariableNameRector.php
index 958b61868d7d..9772a5dd0ba9 100644
--- a/utils/Rector/UnderscoreToCamelCaseVariableNameRector.php
+++ b/utils/Rector/UnderscoreToCamelCaseVariableNameRector.php
@@ -43,7 +43,7 @@ final class UnderscoreToCamelCaseVariableNameRector extends AbstractRector
 
     public function __construct(
         private readonly ReservedKeywordAnalyzer $reservedKeywordAnalyzer,
-        private PhpDocInfoFactory $phpDocInfoFactory
+        private readonly PhpDocInfoFactory $phpDocInfoFactory
     ) {
     }
 

From 71124e70fc87f591c4e26cfe1139d5ece5869723 Mon Sep 17 00:00:00 2001
From: kenjis <kenji.uui@gmail.com>
Date: Tue, 14 Nov 2023 14:24:53 +0900
Subject: [PATCH 21/21] refactor: run rector

---
 app/Views/errors/cli/error_exception.php       |  2 +-
 app/Views/errors/html/error_exception.php      |  4 ++--
 system/CLI/InputOutput.php                     |  2 +-
 .../Utilities/Routes/SampleURIGenerator.php    |  2 +-
 system/Debug/Exceptions.php                    |  4 ++--
 system/Filters/Filters.php                     |  2 +-
 system/Filters/PageCache.php                   |  2 +-
 system/HTTP/Method.php                         | 18 +++++++++---------
 system/Router/Router.php                       |  2 +-
 system/Validation/Rules.php                    |  2 +-
 system/Validation/StrictRules/Rules.php        |  6 +++---
 11 files changed, 23 insertions(+), 23 deletions(-)

diff --git a/app/Views/errors/cli/error_exception.php b/app/Views/errors/cli/error_exception.php
index 49bcd89131fb..e908b426381d 100644
--- a/app/Views/errors/cli/error_exception.php
+++ b/app/Views/errors/cli/error_exception.php
@@ -14,7 +14,7 @@
     $last = $prevException;
 
     CLI::write('  Caused by:');
-    CLI::write('  [' . get_class($prevException) . ']', 'red');
+    CLI::write('  [' . $prevException::class . ']', 'red');
     CLI::write('  ' . $prevException->getMessage());
     CLI::write('  at ' . CLI::color(clean_path($prevException->getFile()) . ':' . $prevException->getLine(), 'green'));
     CLI::newLine();
diff --git a/app/Views/errors/html/error_exception.php b/app/Views/errors/html/error_exception.php
index 2e5571e97e4b..7f4717d4f291 100644
--- a/app/Views/errors/html/error_exception.php
+++ b/app/Views/errors/html/error_exception.php
@@ -55,10 +55,10 @@
 
     <pre>
     Caused by:
-    <?= esc(get_class($prevException)), esc($prevException->getCode() ? ' #' . $prevException->getCode() : '') ?>
+    <?= esc($prevException::class), esc($prevException->getCode() ? ' #' . $prevException->getCode() : '') ?>
 
     <?= nl2br(esc($prevException->getMessage())) ?>
-    <a href="https://www.duckduckgo.com/?q=<?= urlencode(get_class($prevException) . ' ' . preg_replace('#\'.*\'|".*"#Us', '', $prevException->getMessage())) ?>"
+    <a href="https://www.duckduckgo.com/?q=<?= urlencode($prevException::class . ' ' . preg_replace('#\'.*\'|".*"#Us', '', $prevException->getMessage())) ?>"
        rel="noreferrer" target="_blank">search &rarr;</a>
     <?= esc(clean_path($prevException->getFile()) . ':' . $prevException->getLine()) ?>
     </pre>
diff --git a/system/CLI/InputOutput.php b/system/CLI/InputOutput.php
index 5b6c1da02f4d..b69c19e2eee1 100644
--- a/system/CLI/InputOutput.php
+++ b/system/CLI/InputOutput.php
@@ -21,7 +21,7 @@ class InputOutput
     /**
      * Is the readline library on the system?
      */
-    private bool $readlineSupport;
+    private readonly bool $readlineSupport;
 
     public function __construct()
     {
diff --git a/system/Commands/Utilities/Routes/SampleURIGenerator.php b/system/Commands/Utilities/Routes/SampleURIGenerator.php
index 4c4cf0c9112e..c0832a382eff 100644
--- a/system/Commands/Utilities/Routes/SampleURIGenerator.php
+++ b/system/Commands/Utilities/Routes/SampleURIGenerator.php
@@ -52,7 +52,7 @@ public function get(string $routeKey): string
     {
         $sampleUri = $routeKey;
 
-        if (strpos($routeKey, '{locale}') !== false) {
+        if (str_contains($routeKey, '{locale}')) {
             $sampleUri = str_replace(
                 '{locale}',
                 config(App::class)->defaultLocale,
diff --git a/system/Debug/Exceptions.php b/system/Debug/Exceptions.php
index 2ae5890c6acb..dfb5b81bd7bd 100644
--- a/system/Debug/Exceptions.php
+++ b/system/Debug/Exceptions.php
@@ -130,7 +130,7 @@ public function exceptionHandler(Throwable $exception)
             $uri       = $this->request->getPath() === '' ? '/' : $this->request->getPath();
             $routeInfo = '[Method: ' . $this->request->getMethod() . ', Route: ' . $uri . ']';
 
-            log_message('critical', get_class($exception) . ": {message}\n{routeInfo}\nin {exFile} on line {exLine}.\n{trace}", [
+            log_message('critical', $exception::class . ": {message}\n{routeInfo}\nin {exFile} on line {exLine}.\n{trace}", [
                 'message'   => $exception->getMessage(),
                 'routeInfo' => $routeInfo,
                 'exFile'    => clean_path($exception->getFile()), // {file} refers to THIS file
@@ -144,7 +144,7 @@ public function exceptionHandler(Throwable $exception)
             while ($prevException = $last->getPrevious()) {
                 $last = $prevException;
 
-                log_message('critical', '[Caused by] ' . get_class($prevException) . ": {message}\nin {exFile} on line {exLine}.\n{trace}", [
+                log_message('critical', '[Caused by] ' . $prevException::class . ": {message}\nin {exFile} on line {exLine}.\n{trace}", [
                     'message' => $prevException->getMessage(),
                     'exFile'  => clean_path($prevException->getFile()), // {file} refers to THIS file
                     'exLine'  => $prevException->getLine(), // {line} refers to THIS line
diff --git a/system/Filters/Filters.php b/system/Filters/Filters.php
index 6816e72ab482..acfc9970c522 100644
--- a/system/Filters/Filters.php
+++ b/system/Filters/Filters.php
@@ -230,7 +230,7 @@ private function runAfter(array $filterClasses): ResponseInterface
             $class = new $className();
 
             if (! $class instanceof FilterInterface) {
-                throw FilterException::forIncorrectInterface(get_class($class));
+                throw FilterException::forIncorrectInterface($class::class);
             }
 
             $result = $class->after(
diff --git a/system/Filters/PageCache.php b/system/Filters/PageCache.php
index d6fa407f5a0d..c3bb2af90dd6 100644
--- a/system/Filters/PageCache.php
+++ b/system/Filters/PageCache.php
@@ -25,7 +25,7 @@
  */
 class PageCache implements FilterInterface
 {
-    private ResponseCache $pageCache;
+    private readonly ResponseCache $pageCache;
 
     public function __construct()
     {
diff --git a/system/HTTP/Method.php b/system/HTTP/Method.php
index 7aae162b3cba..6ad3847cc2f7 100644
--- a/system/HTTP/Method.php
+++ b/system/HTTP/Method.php
@@ -19,59 +19,59 @@ class Method
     /**
      * @see https://developer.mozilla.org/en-US/docs/Web/HTTP/Methods/CONNECT
      */
-    public const CONNECT = 'CONNECT';
+    final public const CONNECT = 'CONNECT';
 
     /**
      * Idempotent
      *
      * @see https://developer.mozilla.org/en-US/docs/Web/HTTP/Methods/DELETE
      */
-    public const DELETE = 'DELETE';
+    final public const DELETE = 'DELETE';
 
     /**
      * Safe, Idempotent, Cacheable
      *
      * @see https://developer.mozilla.org/en-US/docs/Web/HTTP/Methods/GET
      */
-    public const GET = 'GET';
+    final public const GET = 'GET';
 
     /**
      * Safe, Idempotent, Cacheable
      *
      * @see https://developer.mozilla.org/en-US/docs/Web/HTTP/Methods/HEAD
      */
-    public const HEAD = 'HEAD';
+    final public const HEAD = 'HEAD';
 
     /**
      * Safe, Idempotent
      *
      * @see https://developer.mozilla.org/en-US/docs/Web/HTTP/Methods/OPTIONS
      */
-    public const OPTIONS = 'OPTIONS';
+    final public const OPTIONS = 'OPTIONS';
 
     /**
      * @see https://developer.mozilla.org/en-US/docs/Web/HTTP/Methods/PATCH
      */
-    public const PATCH = 'PATCH';
+    final public const PATCH = 'PATCH';
 
     /**
      * @see https://developer.mozilla.org/en-US/docs/Web/HTTP/Methods/POST
      */
-    public const POST = 'POST';
+    final public const POST = 'POST';
 
     /**
      * Idempotent
      *
      * @see https://developer.mozilla.org/en-US/docs/Web/HTTP/Methods/PUT
      */
-    public const PUT = 'PUT';
+    final public const PUT = 'PUT';
 
     /**
      * Safe, Idempotent
      *
      * @see https://developer.mozilla.org/en-US/docs/Web/HTTP/Methods/TRACE
      */
-    public const TRACE = 'TRACE';
+    final public const TRACE = 'TRACE';
 
     /**
      * Returns all HTTP methods.
diff --git a/system/Router/Router.php b/system/Router/Router.php
index e7b0c087c07d..54005c812cd9 100644
--- a/system/Router/Router.php
+++ b/system/Router/Router.php
@@ -30,7 +30,7 @@ class Router implements RouterInterface
     /**
      * List of allowed HTTP methods (and CLI for command line use).
      */
-    public const HTTP_METHODS = [
+    final public const HTTP_METHODS = [
         Method::GET,
         Method::HEAD,
         Method::POST,
diff --git a/system/Validation/Rules.php b/system/Validation/Rules.php
index 00a4480676f4..d0c609e84699 100644
--- a/system/Validation/Rules.php
+++ b/system/Validation/Rules.php
@@ -444,7 +444,7 @@ public function field_exists(
         ?string $error = null,
         ?string $field = null
     ): bool {
-        if (strpos($field, '.') !== false) {
+        if (str_contains($field, '.')) {
             return ArrayHelper::dotKeyExists($field, $data);
         }
 
diff --git a/system/Validation/StrictRules/Rules.php b/system/Validation/StrictRules/Rules.php
index 712200321764..abb0a6033c1f 100644
--- a/system/Validation/StrictRules/Rules.php
+++ b/system/Validation/StrictRules/Rules.php
@@ -44,7 +44,7 @@ public function differs(
         ?string $error = null,
         ?string $field = null
     ): bool {
-        if (strpos($otherField, '.') !== false) {
+        if (str_contains($otherField, '.')) {
             return $str !== dot_array_search($otherField, $data);
         }
 
@@ -275,7 +275,7 @@ public function matches(
         ?string $error = null,
         ?string $field = null
     ): bool {
-        if (strpos($otherField, '.') !== false) {
+        if (str_contains($otherField, '.')) {
             return $str === dot_array_search($otherField, $data);
         }
 
@@ -420,7 +420,7 @@ public function field_exists(
         ?string $error = null,
         ?string $field = null
     ): bool {
-        if (strpos($field, '.') !== false) {
+        if (str_contains($field, '.')) {
             return ArrayHelper::dotKeyExists($field, $data);
         }