Updated First-class Callable Syntax

src/DateTime.php

@@ -12,12 +12,12 @@ public function __construct($name)
     {
         parent::__construct(
             $name,
-            \Closure::fromCallable($this->compile(...))->bindTo($this),
-            \Closure::fromCallable($this->evaluate(...))->bindTo($this)
+            $this->compile(...)->bindTo($this),
+            $this->evaluate(...)->bindTo($this)
         );
     }
 
-    private function compile(string $date, string $format, string $timezone = null)
+    private function compile(string $date, string $format, string $timezone = null): string
     {
         return <<<"PHP"
                 \\DateTimeImmutable::createFromFormat({$format}, {$date}, {$timezone} !== null ? new \\DateTimeZone({$timezone}) : null)

src/FileName.php

@@ -12,12 +12,12 @@ public function __construct($name)
     {
         parent::__construct(
             $name,
-            \Closure::fromCallable($this->compile(...))->bindTo($this),
-            \Closure::fromCallable($this->evaluate(...))->bindTo($this)
+            $this->compile(...)->bindTo($this),
+            $this->evaluate(...)->bindTo($this)
         );
     }
 
-    private function compile($file)
+    private function compile($file): string
     {
         return <<<COMPILED
             (!is_string({$file}) ? null : pathinfo({$file}, PATHINFO_FILENAME))

src/FormatDate.php

@@ -12,12 +12,12 @@ public function __construct($name)
     {
         parent::__construct(
             $name,
-            \Closure::fromCallable($this->compile(...))->bindTo($this),
-            \Closure::fromCallable($this->evaluate(...))->bindTo($this)
+            $this->compile(...)->bindTo($this),
+            $this->evaluate(...)->bindTo($this)
         );
     }
 
-    private function compile(string $dateTime, string $format)
+    private function compile(string $dateTime, string $format): string
     {
         return <<<"PHP"
                 {$dateTime}->format({$format})

src/Now.php

@@ -12,12 +12,12 @@ public function __construct($name)
     {
         parent::__construct(
             $name,
-            \Closure::fromCallable($this->compile(...))->bindTo($this),
-            \Closure::fromCallable($this->evaluate(...))->bindTo($this)
+            $this->compile(...)->bindTo($this),
+            $this->evaluate(...)->bindTo($this)
         );
     }
 
-    private function compile(string $timezone = null)
+    private function compile(string $timezone = null): string
     {
         return <<<PHP
                 (new \\DateTime('now', {$timezone} !== null ? new \\DateTimeZone({$timezone}) : null))

src/TruncateFileName.php

@@ -17,7 +17,7 @@ public function __construct($name)
         );
     }
 
-    private function compile(string $filename, string $length)
+    private function compile(string $filename, string $length): string
     {
         return <<<PHP
             (

tests/functional/StringExpressionLanguageProviderTest.php

@@ -14,4 +14,11 @@ public function testFormatExpression(): void
 
         $this->assertEquals('SKU_000001', $interpreter->evaluate('format("SKU_%06d", 1)'));
     }
+
+    public function testExpression(): void
+    {
+        $interpreter = new ExpressionLanguage(null, [new StringExpressionLanguageProvider()]);
+
+        $this->assertEquals('SKU_000001', $interpreter->evaluate('fileName("SKU_000001")'));
+    }
 }