Re: [PATCH 1/5] drm/tests: Test drm_rect_intersect()

["Ville Syrjälä" <ville.syrjala@linux.intel.com>]

On Wed, Mar 22, 2023 at 11:06:57AM -0300, Arthur Grillo wrote:
> Insert test for the drm_rect_intersect() function, it also create a
> helper for comparing drm_rects more easily.
> 
> Signed-off-by: Arthur Grillo <arthurgrillo@riseup.net>
> ---
>  drivers/gpu/drm/tests/drm_rect_test.c | 30 +++++++++++++++++++++++++++
>  1 file changed, 30 insertions(+)
> 
> diff --git a/drivers/gpu/drm/tests/drm_rect_test.c b/drivers/gpu/drm/tests/drm_rect_test.c
> index e9809ea32696..f700984f70a8 100644
> --- a/drivers/gpu/drm/tests/drm_rect_test.c
> +++ b/drivers/gpu/drm/tests/drm_rect_test.c
> @@ -9,6 +9,15 @@
>  
>  #include <drm/drm_rect.h>
>  
> +static void drm_rect_compare(struct kunit *test, const struct drm_rect *r,
> +			     const struct drm_rect *expected)
> +{
> +	KUNIT_EXPECT_EQ(test, r->x1, expected->x1);
> +	KUNIT_EXPECT_EQ(test, r->y1, expected->y1);
> +	KUNIT_EXPECT_EQ(test, drm_rect_width(r), drm_rect_width(expected));
> +	KUNIT_EXPECT_EQ(test, drm_rect_height(r), drm_rect_height(expected));
> +}

We already have a drm_rect_equals().

> +
>  static void drm_test_rect_clip_scaled_div_by_zero(struct kunit *test)
>  {
>  	struct drm_rect src, dst, clip;
> @@ -196,11 +205,32 @@ static void drm_test_rect_clip_scaled_signed_vs_unsigned(struct kunit *test)
>  	KUNIT_EXPECT_FALSE_MSG(test, drm_rect_visible(&src), "Source should not be visible\n");
>  }
>  
> +static void drm_test_rect_intersect(struct kunit *test)
> +{
> +	struct drm_rect r1, r2;
> +	bool visible;
> +
> +	drm_rect_init(&r1, 0, 0, 2, 2);
> +	drm_rect_init(&r2, 1, 1, 2, 2);
> +
> +	visible = drm_rect_intersect(&r1, &r2);
> +
> +	KUNIT_EXPECT_TRUE_MSG(test, visible, "Interserction should be a visible rect");
> +	drm_rect_compare(test, &r1, &DRM_RECT_INIT(1, 1, 1, 1));
> +
> +	drm_rect_init(&r1, 0, 0, 1, 1);
> +

I would re-init r2 here too to make it easier to see what we're
actually testing.

I would probably test a few more variations of the overlap between
the rectangles, eg: equal rectangles, one smaller one fully inside
the bigger one, overlaps across different edges/corners.

> +	visible = drm_rect_intersect(&r1, &r2);
> +
> +	KUNIT_EXPECT_FALSE_MSG(test, visible, "Interserction should not be a visible rect");
> +}
> +
>  static struct kunit_case drm_rect_tests[] = {
>  	KUNIT_CASE(drm_test_rect_clip_scaled_div_by_zero),
>  	KUNIT_CASE(drm_test_rect_clip_scaled_not_clipped),
>  	KUNIT_CASE(drm_test_rect_clip_scaled_clipped),
>  	KUNIT_CASE(drm_test_rect_clip_scaled_signed_vs_unsigned),
> +	KUNIT_CASE(drm_test_rect_intersect),
>  	{ }
>  };
>  
> -- 
> 2.39.2

-- 
Ville Syrjälä
Intel