Calls to parent::someMethod should remember type params

[muglug]

/**
 * @template T
 */
class Stringer {
  /**
   * @param T $t
   */
  public static function takesParam($t) : string {
    return "hello";
  }
}

class AParent {}
class A extends AParent {}

/**
 * @template-extends Stringer<A>
 */
class AStringer extends Stringer {
  public static function foo() : string {
    return parent::takesParam("should not be allowed");
  }
}

Expected output

Argument 1 of Stringer::takesParam expects A, string provided

Actual output

No issue - https://phpstan.org/r/c58ef371-1108-4e75-ae3b-b4f9a077ec69

[arnaud-lb]

Do you have examples when it's unsafe ?

[muglug]

This is my best effort so far: https://phpstan.org/r/63f3bd8d-d5c1-4f59-9bbf-a5f91b93e442

But it's also, I think, how generics should work.

[eigan]

I think this might be relevant: https://phpstan.org/r/efdfcc33-84d0-40e3-8b9f-28e2193b52d8

[ondrejmirtes]

@eigan I guess your bug is the same bug as #3251

[phpstan-bot]

@muglug After the latest commit in dev-master, PHPStan now reports different result with your code snippet:

@@ @@
-37: Method AStringer::foo() should return A but returns object.
+No errors

[phpstan-bot]

@eigan After the latest commit in dev-master, PHPStan now reports different result with your code snippet:

@@ @@
-35: Method Child::give() should return B but returns A.
+No errors

[ondrejmirtes]

Fixed: phpstan/phpstan-src@4acbc6c

[github-actions]

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