Re: [PATCH v2 1/5] drm/tests: Test drm_rect_intersect()

[Maíra Canal]

Hi Arthur,

On 3/27/23 10:38, 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 <arthurgri...@riseup.net>
---
  drivers/gpu/drm/tests/drm_rect_test.c | 139 ++++++++++++++++++++++++++
  1 file changed, 139 insertions(+)

diff --git a/drivers/gpu/drm/tests/drm_rect_test.c 
b/drivers/gpu/drm/tests/drm_rect_test.c
index e9809ea32696..3654c0be3d6b 100644
--- a/drivers/gpu/drm/tests/drm_rect_test.c
+++ b/drivers/gpu/drm/tests/drm_rect_test.c
@@ -9,6 +9,17 @@

#include <drm/drm_rect.h> +#include <linux/string_helpers.h>

Is this include really needed? I was able to compile without it.

+
+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);

Maybe it would be nice to have a message here that shows the current x1
and the expected x1. Same for the other dimensions.

+       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));
+}
+
  static void drm_test_rect_clip_scaled_div_by_zero(struct kunit *test)
  {
        struct drm_rect src, dst, clip;
@@ -196,11 +207,139 @@ 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");
  }

+struct drm_rect_intersect_case {

+       const char *description;
+       struct drm_rect r1, r2;
+       bool should_be_visible;
+       struct drm_rect expected_intersection;
+};
+
+static const struct drm_rect_intersect_case drm_rect_intersect_cases[] = {
+       {
+               .description = "top-left X bottom-right",
+               .r1 = DRM_RECT_INIT(1, 1, 2, 2),
+               .r2 = DRM_RECT_INIT(0, 0, 2, 2),
+               .should_be_visible = true,
+               .expected_intersection = DRM_RECT_INIT(1, 1, 1, 1),
+       },
+       {
+               .description = "top-right X bottom-left",
+               .r1 = DRM_RECT_INIT(0, 0, 2, 2),
+               .r2 = DRM_RECT_INIT(1, -1, 2, 2),
+               .should_be_visible = true,
+               .expected_intersection = DRM_RECT_INIT(1, 0, 1, 1),
+       },
+       {
+               .description = "bottom-left X top-right",
+               .r1 = DRM_RECT_INIT(1, -1, 2, 2),
+               .r2 = DRM_RECT_INIT(0, 0, 2, 2),
+               .should_be_visible = true,
+               .expected_intersection = DRM_RECT_INIT(1, 0, 1, 1),
+       },
+       {
+               .description = "bottom-right X top-left",
+               .r1 = DRM_RECT_INIT(0, 0, 2, 2),
+               .r2 = DRM_RECT_INIT(1, 1, 2, 2),
+               .should_be_visible = true,
+               .expected_intersection = DRM_RECT_INIT(1, 1, 1, 1),
+       },
+       {
+               .description = "right X left",
+               .r1 = DRM_RECT_INIT(0, 0, 2, 1),
+               .r2 = DRM_RECT_INIT(1, 0, 3, 1),
+               .should_be_visible = true,
+               .expected_intersection = DRM_RECT_INIT(1, 0, 1, 1),
+       },
+       {
+               .description = "left X right",
+               .r1 = DRM_RECT_INIT(1, 0, 3, 1),
+               .r2 = DRM_RECT_INIT(0, 0, 2, 1),
+               .should_be_visible = true,
+               .expected_intersection = DRM_RECT_INIT(1, 0, 1, 1),
+       },
+       {
+               .description = "up X bottom",
+               .r1 = DRM_RECT_INIT(0, 0, 1, 2),
+               .r2 = DRM_RECT_INIT(0, -1, 1, 3),
+               .should_be_visible = true,
+               .expected_intersection = DRM_RECT_INIT(0, 0, 1, 2),
+       },
+       {
+               .description = "bottom X up",
+               .r1 = DRM_RECT_INIT(0, -1, 1, 3),
+               .r2 = DRM_RECT_INIT(0, 0, 1, 2),
+               .should_be_visible = true,
+               .expected_intersection = DRM_RECT_INIT(0, 0, 1, 2),
+       },
+       {
+               .description = "touching corner",
+               .r1 = DRM_RECT_INIT(0, 0, 1, 1),
+               .r2 = DRM_RECT_INIT(1, 1, 2, 2),
+               .should_be_visible = false,
+               .expected_intersection = DRM_RECT_INIT(1, 1, 0, 0),
+       },
+       {
+               .description = "touching side",
+               .r1 = DRM_RECT_INIT(0, 0, 1, 1),
+               .r2 = DRM_RECT_INIT(1, 0, 1, 1),
+               .should_be_visible = false,
+               .expected_intersection = DRM_RECT_INIT(1, 0, 0, 1),
+       },
+       {
+               .description = "equal rects",
+               .r1 = DRM_RECT_INIT(0, 0, 2, 2),
+               .r2 = DRM_RECT_INIT(0, 0, 2, 2),
+               .should_be_visible = true,
+               .expected_intersection = DRM_RECT_INIT(0, 0, 2, 2),
+       },
+       {
+               .description = "inside another",
+               .r1 = DRM_RECT_INIT(0, 0, 2, 2),
+               .r2 = DRM_RECT_INIT(1, 1, 1, 1),
+               .should_be_visible = true,
+               .expected_intersection = DRM_RECT_INIT(1, 1, 1, 1),
+       },
+       {
+               .description = "far away",
+               .r1 = DRM_RECT_INIT(0, 0, 1, 1),
+               .r2 = DRM_RECT_INIT(3, 6, 1, 1),
+               .should_be_visible = false,
+               .expected_intersection = DRM_RECT_INIT(3, 6, -2, -5),
+       },
+};

What happens if width = height = 0? It would be nice to have a test
case for this scenario.

+
+static void drm_rect_intersect_case_desc(const struct drm_rect_intersect_case 
*t, char *desc)
+{
+       if (!t->description)
+               snprintf(desc, KUNIT_PARAM_DESC_SIZE,
+                        DRM_RECT_FMT " X " DRM_RECT_FMT,
+                        DRM_RECT_ARG(&t->r1), DRM_RECT_ARG(&t->r2));

Is this conditional clause really needed? All parameters have
description.

+       else
+               snprintf(desc, KUNIT_PARAM_DESC_SIZE,
+                        "%s: " DRM_RECT_FMT " X " DRM_RECT_FMT,
+                        t->description, DRM_RECT_ARG(&t->r1), 
DRM_RECT_ARG(&t->r2));
+}
+
+KUNIT_ARRAY_PARAM(drm_rect_intersect, drm_rect_intersect_cases, 
drm_rect_intersect_case_desc);
+
+static void drm_test_rect_intersect(struct kunit *test)
+{
+       const struct drm_rect_intersect_case *params = test->param_value;
+       struct drm_rect r1_aux = params->r1;

Does this variable needs to exist? I guess you could just use params->r1.

Best Regards,
- Maíra Canal

+       bool visible;
+
+       visible = drm_rect_intersect(&r1_aux, &params->r2);
+
+       KUNIT_EXPECT_EQ(test, visible, params->should_be_visible);
+       drm_rect_compare(test, &r1_aux, &params->expected_intersection);
+}
+
  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_PARAM(drm_test_rect_intersect, 
drm_rect_intersect_gen_params),
        { }
  };