argument.staticClosure

Code example

<?php declare(strict_types = 1);

class Foo
{
	/**
	 * @param-closure-this Foo $callback
	 */
	public function doFoo(Closure $callback): void
	{
	}
}

$foo = new Foo();
$foo->doFoo(static function (): void {
	// ...
});

Why is it reported?

The parameter expects a bindable closure (one that can access $this), but a static closure was passed. Static closures declared with the static keyword cannot be bound to an object, so they cannot access $this.

A method advertises that its parameter needs a bindable closure by using the @param-closure-this PHPDoc tag. Passing a static closure to such a parameter will fail at runtime.

How to fix it

Remove the static keyword from the closure:

-$foo->doFoo(static function (): void {
+$foo->doFoo(function (): void {
 	// ...
 });