Add simple draw line test

test.c

@@ -28,6 +28,12 @@
 #define WIDTH 128
 #define HEIGHT 128
 
+#define BACKGROUND_COLOR 0xFF202020
+#define RED_COLOR 0xFF2020AA
+#define GREEN_COLOR 0xFF20AA20
+#define BLUE_COLOR 0xFFAA2020
+#define ERROR_COLOR 0xFFFF00FF
+
 #define TEST_DIR_PATH "./test"
 
 uint32_t pixels[WIDTH*HEIGHT];
@@ -42,7 +48,7 @@ bool record_test_case(const char *file_path)
     return(true);
 }
 
-bool replay_test_case(const char *file_path, const char *failure_file_path)
+bool replay_test_case(const char *program_path, const char *file_path, const char *failure_file_path)
 {
     bool result = true;
     uint32_t *expected_pixels = NULL;
@@ -51,12 +57,16 @@ bool replay_test_case(const char *file_path, const char *failure_file_path)
         int expected_width, expected_height;
         expected_pixels = (uint32_t*) stbi_load(file_path, &expected_width, &expected_height, NULL, 4);
         if (expected_pixels == NULL) {
-            fprintf(stderr, "ERROR: could not read file %s: %s\n", file_path, strerror(errno));
+            fprintf(stderr, "%s: TEST FAILURE: could not read the file: %s\n", file_path, strerror(errno));
+            if (errno == ENOENT) {
+                fprintf(stderr, "%s: HINT: Consider running `%s record` to create it\n", file_path, program_path);
+            }
             return_defer(false);
         }
 
+        // TODO: it would be cool if "unexpected image size" error would generate the image diff as well
         if (expected_width != WIDTH || expected_height != HEIGHT) {
-            fprintf(stderr, "%s: FAILURE: unexpected image size. Expected %dx%d, but got %dx%d\n",
+            fprintf(stderr, "%s: TEST FAILURE: unexpected image size. Expected %dx%d, but got %dx%d\n",
                     file_path, expected_width, expected_height, WIDTH, HEIGHT);
             return_defer(false);
         }
@@ -67,14 +77,14 @@ bool replay_test_case(const char *file_path, const char *failure_file_path)
                 uint32_t expected_pixel = expected_pixels[y*WIDTH + x];
                 uint32_t actual_pixel = pixels[y*WIDTH + x];
                 if (expected_pixel != actual_pixel) {
-                    pixels[y*WIDTH + x] = 0xFF0000FF;
+                    pixels[y*WIDTH + x] = ERROR_COLOR;
                     failed = true;
                 }
             }
         }
 
         if (failed) {
-            fprintf(stderr, "%s: FAILURE: unexpected pixels in generated image\n", file_path);
+            fprintf(stderr, "%s: TEST FAILURE: unexpected pixels in generated image\n", file_path);
             if (!stbi_write_png(failure_file_path, WIDTH, HEIGHT, 4, pixels, sizeof(uint32_t)*WIDTH)) {
                 fprintf(stderr, "ERROR: could not generate image diff %s: %s\n", failure_file_path, strerror(errno));
             } else {
@@ -106,28 +116,38 @@ typedef struct {
 
 void test_fill_rect(void)
 {
-    olivec_fill(pixels, WIDTH, HEIGHT, 0xFF202020);
-    olivec_fill_rect(pixels, WIDTH, HEIGHT, WIDTH/2 - WIDTH/8, HEIGHT/2 - HEIGHT/8, WIDTH/4, HEIGHT/4, 0xFF2020AA);
-    olivec_fill_rect(pixels, WIDTH, HEIGHT, WIDTH - 1, HEIGHT - 1, -WIDTH/2, -HEIGHT/2, 0xFF20AA20);
-    olivec_fill_rect(pixels, WIDTH, HEIGHT, -WIDTH/4, -HEIGHT/4, WIDTH/2, HEIGHT/2, 0xFFAA2020);
+    olivec_fill(pixels, WIDTH, HEIGHT, BACKGROUND_COLOR);
+    olivec_fill_rect(pixels, WIDTH, HEIGHT, WIDTH/2 - WIDTH/8, HEIGHT/2 - HEIGHT/8, WIDTH/4, HEIGHT/4, RED_COLOR);
+    olivec_fill_rect(pixels, WIDTH, HEIGHT, WIDTH - 1, HEIGHT - 1, -WIDTH/2, -HEIGHT/2, GREEN_COLOR);
+    olivec_fill_rect(pixels, WIDTH, HEIGHT, -WIDTH/4, -HEIGHT/4, WIDTH/2, HEIGHT/2, BLUE_COLOR);
 }
 
 void test_fill_circle(void)
 {
-    olivec_fill(pixels, WIDTH, HEIGHT, 0xFF202020);
-    olivec_fill_circle(pixels, WIDTH, HEIGHT, 0, 0, WIDTH/2, 0xFF2020AA);
-    olivec_fill_circle(pixels, WIDTH, HEIGHT, WIDTH/2, HEIGHT/2, WIDTH/4, 0xFFAA2020);
-    olivec_fill_circle(pixels, WIDTH, HEIGHT, WIDTH*3/4, HEIGHT*3/4, -WIDTH/4, 0xFF20AA20);
+    olivec_fill(pixels, WIDTH, HEIGHT, BACKGROUND_COLOR);
+    olivec_fill_circle(pixels, WIDTH, HEIGHT, 0, 0, WIDTH/2, RED_COLOR);
+    olivec_fill_circle(pixels, WIDTH, HEIGHT, WIDTH/2, HEIGHT/2, WIDTH/4, BLUE_COLOR);
+    olivec_fill_circle(pixels, WIDTH, HEIGHT, WIDTH*3/4, HEIGHT*3/4, -WIDTH/4, GREEN_COLOR);
+}
+
+void test_draw_line(void)
+{
+    olivec_fill(pixels, WIDTH, HEIGHT, BACKGROUND_COLOR);
+    olivec_draw_line(pixels, WIDTH, HEIGHT, 0, 0, WIDTH, HEIGHT, RED_COLOR);
+    olivec_draw_line(pixels, WIDTH, HEIGHT, WIDTH, 0, 0, HEIGHT, RED_COLOR);
 }
 
 Test_Case test_cases[] = {
     DEFINE_TEST_CASE(test_fill_rect),
     DEFINE_TEST_CASE(test_fill_circle),
+    DEFINE_TEST_CASE(test_draw_line),
 };
 #define TEST_CASES_COUNT (sizeof(test_cases)/sizeof(test_cases[0]))
 
 int main(int argc, char **argv)
 {
+    assert(argc >= 1);
+    const char *program_path = argv[0];
     bool record = argc >= 2 && strcmp(argv[1], "record") == 0;
 
     for (size_t i = 0; i < TEST_CASES_COUNT; ++i) {
@@ -135,7 +155,7 @@ int main(int argc, char **argv)
         if (record) {
             if (!record_test_case(test_cases[i].file_path)) return 1;
         } else {
-            if (!replay_test_case(test_cases[i].file_path, test_cases[i].failure_file_path)) return 1;
+            if (!replay_test_case(program_path, test_cases[i].file_path, test_cases[i].failure_file_path)) return 1;
         }
     }
     return 0;