get_class_methods($closure) doesn't return __invoke

[faizanakram99]

Description

The following code:

<?php

$closure = fn (string $str) => "hello {$str}";

print_r(get_class_methods($closure));

Resulted in this output:

Array
(
    [0] => bind
    [1] => bindTo
    [2] => call
    [3] => fromCallable
)

But I expected this output instead:

Array
(
    [0] => bind
    [1] => bindTo
    [2] => call
    [3] => fromCallable
    [4] => __invoke
)

__invoke does exist on Closures, it is documented too, see https://3v4l.org/VKjAF

From https://www.php.net/manual/en/class.closure.php

Besides the methods listed here, this class also has an __invoke method. This is for consistency with other classes that implement calling magic, as this method is not used for calling the function.

PHP Version

8.2

Operating System

No response

[TimWolla]

Interestingly the method is already visible to ReflectionClass, but is missing information for getParameters() compared to ReflectionFunction directly on the Closure:

<?php

$closure = fn (string $str) => "hello {$str}";

$r = new ReflectionClass($closure);
var_dump($r->getMethod('__invoke')->getParameters());
$r = new ReflectionFunction($closure);
var_dump($r->getParameters());

[cmb69]

php-src/Zend/zend_closures_arginfo.h

Lines 33 to 40 in 0cc0c7c

	static const zend_function_entry class_Closure_methods[] = {
	ZEND_ME(Closure, __construct, arginfo_class_Closure___construct, ZEND_ACC_PRIVATE)
	ZEND_ME(Closure, bind, arginfo_class_Closure_bind, ZEND_ACC_PUBLIC|ZEND_ACC_STATIC)
	ZEND_ME(Closure, bindTo, arginfo_class_Closure_bindTo, ZEND_ACC_PUBLIC)
	ZEND_ME(Closure, call, arginfo_class_Closure_call, ZEND_ACC_PUBLIC)
	ZEND_ME(Closure, fromCallable, arginfo_class_Closure_fromCallable, ZEND_ACC_PUBLIC|ZEND_ACC_STATIC)
	ZEND_FE_END
	};

vs

php-src/ext/reflection/php_reflection.c

Lines 4576 to 4590 in 0cc0c7c

	if (!Z_ISUNDEF(intern->obj) && is_closure_invoke(ce, lc_name)
	&& (mptr = zend_get_closure_invoke_method(Z_OBJ(intern->obj))) != NULL)
	{
	/* don't assign closure_object since we only reflect the invoke handler
	method and not the closure definition itself */
	reflection_method_factory(ce, mptr, NULL, return_value);
	} else if (Z_ISUNDEF(intern->obj) && is_closure_invoke(ce, lc_name)
	&& object_init_ex(&obj_tmp, ce) == SUCCESS && (mptr = zend_get_closure_invoke_method(Z_OBJ(obj_tmp))) != NULL) {
	/* don't assign closure_object since we only reflect the invoke handler
	method and not the closure definition itself */
	reflection_method_factory(ce, mptr, NULL, return_value);
	zval_ptr_dtor(&obj_tmp);
	} else if ((mptr = zend_hash_find_ptr(&ce->function_table, lc_name)) != NULL) {
	reflection_method_factory(ce, mptr, NULL, return_value);
	} else {

So ReflectionClass::getMethod() is special cased for closures, but since there is no arg_info, there are no parameters known. Since these depend on the individual closure, they couldn't be reported for the class, which is likely also the reason that __invoke() is omitted from the method table in the first place.