test: add failing test for changing_attributes check for create

[vonagam]

Based on code and previous behavior (before being switched to filter from match) changing_attributes should work with create actions. But currently it does not.

[zachdaniel]

Changing the test to

  test "filter policies are applied in create" do
    assert_raise Ash.Error.Forbidden, fn ->
      AshPostgres.Test.Post
      |> Ash.Changeset.for_create(:create, %{title: "worst"}, authorize?: true)
      |> Ash.create!()
    end
  end

makes it pass, so I don't have a reproduction of the issue. However, I did notice that if you were using the :from option in the policy, i.e from: nil, to: "foo" that it would have caused it to appear as false, so I'm going to amend the changing_attributes policy to consider all attributes as going from nil to the value in ash core.

[zachdaniel]

This is because the ash_postgres domain has

  authorization do
    authorize(:when_requested)
  end

[vonagam]

Ah, missed that. I was having that issue on Ash 2 so assumed that the issue was reproduced on Ash 3 when got the failing test.