added stringable objects as a possible parameter

Author: transistive

src/ParameterHelper.php

@@ -41,9 +41,22 @@ public static function asParameter($value)
         return self::emptySequenceToArray($value) ??
             self::emptyDictionaryToStdClass($value) ??
             self::filledIterableToArray($value) ??
+            self::stringableToString($value) ??
             self::filterInvalidType($value);
     }
 
+    /**
+     * @param mixed $value
+     */
+    private static function stringableToString($value): ?string
+    {
+        if (is_object($value) && method_exists($value, '__toString')) {
+            return (string) $value;
+        }
+
+        return null;
+    }
+
     /**
      * @param mixed $value
      *
@@ -52,7 +65,7 @@ public static function asParameter($value)
     private static function filterInvalidType($value)
     {
         if ($value !== null && !is_scalar($value)) {
-            throw new InvalidArgumentException('Parameters must be iterable, scalar or null');
+            throw new InvalidArgumentException('Parameters must be iterable, scalar, null or stringable');
         }
 
         return $value;

tests/Unit/ParameterHelperTest.php

@@ -135,4 +135,15 @@ public function testAsParmeterEmptyArray(): void
         $result = ParameterHelper::asParameter([]);
         self::assertInstanceOf(stdClass::class, $result);
     }
+
+    public function testStringable(): void
+    {
+        $result = ParameterHelper::asParameter(new class() {
+            public function __toString(): string
+            {
+                return 'abc';
+            }
+        });
+        self::assertEquals('abc', $result);
+    }
 }