public function test_action_recursion() {
    $tag = __FUNCTION__;
    $a   = new MockAction();
    $b   = new MockAction();

    add_action( $tag, array( $a, 'action' ), 11, 1 );
    add_action( $tag, array( $b, 'action' ), 13, 1 );
    add_action( $tag, array( $this, 'action_that_causes_recursion' ), 12, 1 );
    do_action( $tag, $tag );

    $this->assertSame( 2, $a->get_call_count(), 'recursive actions should call all callbacks with earlier priority' );
    $this->assertSame( 2, $b->get_call_count(), 'recursive actions should call callbacks with later priority' );
  }