To avoid users from having to deal with conflict resolution, do away …

…with the Runkit trait in favor of more static methods on the Runkit support class

composer.json

@@ -44,7 +44,7 @@
             "Tests\\": "tests/"
         },
         "files": [
-            "tests/Support/functions.php"
+            "tests/stubs/functions.php"
         ]
     },
     "config": {

phpstan.neon.dist

@@ -24,3 +24,7 @@ parameters:
             paths:
                 - tests/FixtureTest.php
                 - tests/FunctionsTest.php
+
+        -
+            message: '#Call to an undefined static method \S+#'
+            path: tests/Support/RunkitTest.php

src/Constants.php

@@ -7,8 +7,6 @@
 
 trait Constants
 {
-    use Concerns\Runkit;
-
     /**
      * All constants being handled by this trait.
      *
@@ -43,6 +41,8 @@ protected function restoreConstants()
 
             unset($this->constants['created'][$key]);
         }
+
+        Runkit::reset();
     }
 
     /**
@@ -59,7 +59,9 @@ protected function restoreConstants()
      */
     protected function setConstant($name, $value = null)
     {
-        $this->requiresRunkit('setConstant() requires Runkit be available, skipping.');
+        if (! Runkit::isAvailable()) {
+            $this->markTestSkipped('setConstant() requires Runkit be available, skipping.');
+        }
 
         if (defined($name)) {
             if (! isset($this->constants['updated'][$name])) {
@@ -96,7 +98,9 @@ protected function deleteConstant($name)
             return $this;
         }
 
-        $this->requiresRunkit('deleteConstant() requires Runkit be available, skipping.');
+        if (! Runkit::isAvailable()) {
+            $this->markTestSkipped('deleteConstant() requires Runkit be available, skipping.');
+        }
 
         if (! isset($this->constants[$name])) {
             $this->constants['updated'][$name] = constant($name);

src/Functions.php

@@ -8,8 +8,6 @@
 
 trait Functions
 {
-    use Concerns\Runkit;
-
     /**
      * All functions being handled by this trait.
      *
@@ -41,6 +39,8 @@ protected function restoreFunctions()
 
         array_map([Runkit::class, 'function_remove'], $this->functions['defined']);
         $this->functions['defined'] = [];
+
+        Runkit::reset();
     }
 
     /**
@@ -64,7 +64,9 @@ protected function defineFunction($name, \Closure $closure)
             ));
         }
 
-        $this->requiresRunkit('defineFunction() requires Runkit be available, skipping.');
+        if (! Runkit::isAvailable()) {
+            $this->markTestSkipped('defineFunction() requires Runkit be available, skipping.');
+        }
 
         if (! Runkit::function_add($name, $closure)) {
             throw new RunkitException(sprintf('Unable to define function %1$s().', $name));
@@ -91,11 +93,13 @@ protected function redefineFunction($name, \Closure $closure)
             return $this->defineFunction($name, $closure);
         }
 
-        $this->requiresRunkit('redefineFunction() requires Runkit be available, skipping.');
+        if (! Runkit::isAvailable()) {
+            $this->markTestSkipped('redefineFunction() requires Runkit be available, skipping.');
+        }
 
         // Back up the original version of the function.
         if (! isset($this->functions['redefined'][$name])) {
-            $namespaced = $this->runkitNamespace($name);
+            $namespaced = Runkit::makeNamespaced($name);
 
             if (! Runkit::function_rename($name, $namespaced)) {
                 throw new RunkitException(sprintf('Unable to back up %1$s(), aborting.', $name));
@@ -126,7 +130,7 @@ protected function deleteFunction($name)
             return $this;
         }
 
-        $namespaced = $this->runkitNamespace($name);
+        $namespaced = Runkit::makeNamespaced($name);
 
         if (! Runkit::function_rename($name, $namespaced)) {
             throw new RunkitException(sprintf('Unable to back up %1$s(), aborting.', $name));

src/Support/Runkit.php

@@ -32,6 +32,13 @@
  */
 class Runkit
 {
+    /**
+     * A namespace used to move things out of the way for the duration of a test.
+     *
+     * @var string
+     */
+    private static $namespace;
+
     /**
      * Dynamically alias methods to the underlying Runkit functions.
      *
@@ -57,4 +64,61 @@ public static function __callStatic($name, array $args = [])
             $name
         ));
     }
+
+    /**
+     * Determine whether or not Runkit is available in the current environment.
+     *
+     * @return bool
+     */
+    public static function isAvailable()
+    {
+        return function_exists('runkit7_constant_redefine')
+            || function_exists('runkit_constant_redefine');
+    }
+
+    /**
+     * Get the current runkit namespace.
+     *
+     * If the property is currently empty, one will be created.
+     *
+     * @return string The namespace (with trailing backslash) where we're moving functions,
+     *                constants, etc. during tests.
+     */
+    public static function getNamespace()
+    {
+        if (empty(self::$namespace)) {
+            self::$namespace = uniqid(__NAMESPACE__ . '\\runkit_') . '\\';
+        }
+
+        return self::$namespace;
+    }
+
+    /**
+     * Namespace the given reference.
+     *
+     * @param string $var The item to be moved into the temporary test namespace.
+     *
+     * @return string The newly-namespaced item.
+     */
+    public static function makeNamespaced($var)
+    {
+        // Strip leading backslashes.
+        if (0 === mb_strpos($var, '\\')) {
+            $var = mb_substr($var, 1);
+        }
+
+        return self::getNamespace() . $var;
+    }
+
+    /**
+     * Reset static properties.
+     *
+     * This is helpful to run before tests in case self::$namespace gets polluted.
+     *
+     * @return void
+     */
+    public static function reset()
+    {
+        self::$namespace = '';
+    }
 }