Re: [PATCH] Documentation: kunit: Fix kunit_device_register() example

[Robin Murphy <robin.murphy@arm.com>]

On 2025-10-15 2:46 pm, Robin Murphy wrote:
> kunit_device_register() only returns error pointers, not NULL.
> Furthermore for regular users who aren't testing the KUnit API
> itself, errors most likely represent major system failure (e.g. OOM
> or sysfs collision) beyond the scope of their own test conditions.
> Replace the assert with straightforward error handling for clarity.
> 
> Signed-off-by: Robin Murphy <robin.murphy@arm.com>
> ---
> This seemed the logical conclusion by inspection, but please do correct
> me if I've misunderstood the intent...
> ---
>   Documentation/dev-tools/kunit/usage.rst | 3 ++-
>   1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/Documentation/dev-tools/kunit/usage.rst b/Documentation/dev-tools/kunit/usage.rst
> index 038f480074fd..3452c739dd44 100644
> --- a/Documentation/dev-tools/kunit/usage.rst
> +++ b/Documentation/dev-tools/kunit/usage.rst
> @@ -873,7 +873,8 @@ For example:
>   
>   		// Create a fake device.
>   		fake_device = kunit_device_register(test, "my_device");
> -		KUNIT_ASSERT_NOT_ERR_OR_NULL(test, fake_device)
> +		if (IS_ERR(fake_device))
> +			return;

On further consideration, I guess kunit_skip() (as used in various other 
places) is actually what I want here?

Basically, as someone looking at KUnit with fresh eyes it seems 
intuitive to me that not being able to run a test case is a not a 
failure of the thing being tested, so shouldn't be reported as such, and 
thus this example stood out. I for one wouldn't want to be getting CI 
notifications to go and debug a "regression" in my code just because a 
runner OOM'd, for example :)

Thanks,
Robin.
  >
>   		// Pass it to functions which need a device.
>   		dev_managed_string = devm_kstrdup(fake_device, "Hello, World!");