Re: [PATCH] kunit: tool: fix pre-existing python type annotation errors

From: David Gow <davidgow@google.com>
To: Daniel Latypov <dlatypov@google.com>
Cc: Brendan Higgins <brendanhiggins@google.com>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	"open list:KERNEL SELFTEST FRAMEWORK" 
	<linux-kselftest@vger.kernel.org>,
	Shuah Khan <skhan@linuxfoundation.org>
Subject: Re: [PATCH] kunit: tool: fix pre-existing python type annotation errors
Date: Fri, 30 Oct 2020 10:56:39 +0800	[thread overview]
Message-ID: <CABVgOSkXfWihPN5-1dPn2BstpJ7eiG1Qj=cg5EL2oEhv=YHj4g@mail.gmail.com> (raw)
In-Reply-To: <20201021220752.418832-1-dlatypov@google.com>

On Thu, Oct 22, 2020 at 6:08 AM Daniel Latypov <dlatypov@google.com> wrote:
>
> The code uses annotations, but they aren't accurate.
> Note that type checking in python is a separate process, running
> `kunit.py run` will not check and complain about invalid types at
> runtime.
>
> Fix pre-existing issues found by running a type checker
> $ mypy *.py
>
> All but one of these were returning `None` without denoting this
> properly (via `Optional[Type]`).
>
> Signed-off-by: Daniel Latypov <dlatypov@google.com>
> ---

I'm not going to pretend to really understand python annotations
completely, but this all seems correct from what I know of the code,
and I was able to install mypy and verify the issues were fixed.

Clearly, if we're going to have type annotations here, we should be
verifying the code against them. Is there a way we could get python
itself to verify this code when the script runs, rather than have to
use mypy as a tool to verify it separately? Otherwise, maybe we can
run it automatically from the kunit_tool_test.py unit tests or
something similar?

Regardless, this is

Reviewed-by: David Gow <davidgow@google.com>

Cheers,
-- David