[8.x] Improves Support\Reflector to support checking interfaces (#40822)

* Update Reflector.php

* Update SupportReflectorTest.php

Author: hassanhe

src/Illuminate/Support/Reflector.php

@@ -136,7 +136,8 @@ public static function isParameterSubclassOf($parameter, $className)
         $paramClassName = static::getParameterClassName($parameter);
 
         return $paramClassName
-            && class_exists($paramClassName)
+            && (class_exists($paramClassName) ||
+                interface_exists($paramClassName))
             && (new ReflectionClass($paramClassName))->isSubclassOf($className);
     }
 }

tests/Support/SupportReflectorTest.php

@@ -48,6 +48,13 @@ public function testParentClassName()
         $this->assertSame(A::class, Reflector::getParameterClassName($method->getParameters()[0]));
     }
 
+    public function testParameterSubclassOfInterface()
+    {
+        $method = (new ReflectionClass(TestClassWithInterfaceSubclassParameter::class))->getMethod('f');
+
+        $this->assertTrue(Reflector::isParameterSubclassOf($method->getParameters()[0], IA::class));
+    }
+
     /**
      * @requires PHP >= 8
      */
@@ -95,8 +102,7 @@ public function f(A|Model $x)
     {
         //
     }
-}'
-    );
+}');
 }
 
 class TestClassWithCall
@@ -114,3 +120,19 @@ public static function __callStatic($method, $parameters)
         //
     }
 }
+
+interface IA
+{
+}
+
+interface IB extends IA
+{
+}
+
+class TestClassWithInterfaceSubclassParameter
+{
+    public function f(IB $x)
+    {
+        //
+    }
+}