Add tests for color (#171)

Author: tuupola

tests/Makefile

@@ -18,7 +18,7 @@ SRCS = \
     ../src/hagl_blit.c \
     ../src/rgb565.c
 
-all: test_fill_polygon test_polygon test_fill_rectangle test_rectangle test_pixel test_line test_hline test_vline test_circle test_ellipse test_fill_ellipse test_clip test_blit test_fontx test_char test_fps test_aps
+all: test_fill_polygon test_polygon test_fill_rectangle test_rectangle test_pixel test_line test_hline test_vline test_circle test_ellipse test_fill_ellipse test_clip test_blit test_fontx test_char test_fps test_aps test_color
 
 test_fill_polygon: test_fill_polygon.c save_image.c $(SRCS)
 	$(CC) $(CFLAGS) -o $@ $^ $(LDFLAGS)
@@ -71,7 +71,10 @@ test_fps: test_fps.c
 test_aps: test_aps.c
 	$(CC) $(CFLAGS) -o $@ $^ $(LDFLAGS)
 
-test: test_fill_polygon test_polygon test_fill_rectangle test_rectangle test_pixel test_line test_hline test_vline test_circle test_ellipse test_fill_ellipse test_clip test_blit test_fontx test_char test_fps test_aps
+test_color: test_color.c ../src/hagl_color.c ../src/hagl_bitmap.c ../src/rgb565.c
+	$(CC) $(CFLAGS) -o $@ $^ $(LDFLAGS)
+
+test: test_fill_polygon test_polygon test_fill_rectangle test_rectangle test_pixel test_line test_hline test_vline test_circle test_ellipse test_fill_ellipse test_clip test_blit test_fontx test_char test_fps test_aps test_color
 	./test_fill_polygon
 	./test_polygon
 	./test_fill_rectangle
@@ -88,9 +91,11 @@ test: test_fill_polygon test_polygon test_fill_rectangle test_rectangle test_pix
 	./test_fontx
 	./test_char
 	./test_fps
+	./test_aps
+	./test_color
 
 clean:
-	rm -f test_fill_polygon test_polygon test_fill_rectangle test_rectangle test_pixel test_line test_hline test_vline test_circle test_ellipse test_fill_ellipse test_clip test_blit test_fontx test_char test_fps test_aps
+	rm -f test_fill_polygon test_polygon test_fill_rectangle test_rectangle test_pixel test_line test_hline test_vline test_circle test_ellipse test_fill_ellipse test_clip test_blit test_fontx test_char test_fps test_aps test_color
 	rm -rf output
 
 .PHONY: all test clean

tests/test_color.c

@@ -0,0 +1,127 @@
+/*
+
+MIT License
+
+Copyright (c) 2026 Mika Tuupola
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+
+-cut-
+
+This file is part of the HAGL graphics library:
+https://github.com/tuupola/hagl
+
+SPDX-License-Identifier: MIT
+
+*/
+
+#include <stdint.h>
+
+#include "greatest.h"
+#include "hagl/bitmap.h"
+#include "hagl/color.h"
+#include "rgb565.h"
+
+#define TEST_WIDTH 320
+#define TEST_HEIGHT 240
+#define TEST_DEPTH 16
+
+static hagl_bitmap_t bitmap;
+static uint8_t buffer[TEST_WIDTH * TEST_HEIGHT * (TEST_DEPTH / 8)];
+
+static uint8_t last_r, last_g, last_b;
+static hagl_color_t mock_color_result;
+
+static hagl_color_t mock_color(void *self, uint8_t r, uint8_t g, uint8_t b) {
+    last_r = r;
+    last_g = g;
+    last_b = b;
+    return mock_color_result;
+}
+
+static void setup_callback(void *data) {
+    memset(buffer, 0, sizeof(buffer));
+    hagl_bitmap_init(&bitmap, TEST_WIDTH, TEST_HEIGHT, TEST_DEPTH, buffer);
+    last_r = last_g = last_b = 0;
+    mock_color_result = 0;
+}
+
+TEST test_color_default_black(void) {
+    bitmap.color = NULL;
+
+    hagl_color_t result = hagl_color(&bitmap, 0, 0, 0);
+    hagl_color_t expected = rgb565(0, 0, 0);
+
+    ASSERT_EQ(expected, result);
+
+    PASS();
+}
+
+TEST test_color_default_white(void) {
+    bitmap.color = NULL;
+
+    hagl_color_t result = hagl_color(&bitmap, 255, 255, 255);
+    hagl_color_t expected = rgb565(255, 255, 255);
+
+    ASSERT_EQ(expected, result);
+
+    PASS();
+}
+
+TEST test_color_fallback_arbitrary(void) {
+    bitmap.color = NULL;
+
+    uint8_t r = 128, g = 64, b = 32;
+    hagl_color_t result = hagl_color(&bitmap, r, g, b);
+    hagl_color_t expected = rgb565(r, g, b);
+
+    ASSERT_EQ(expected, result);
+
+    PASS();
+}
+
+TEST test_color_delegates_to_surface(void) {
+    bitmap.color = mock_color;
+    mock_color_result = 0x1234;
+
+    hagl_color_t result = hagl_color(&bitmap, 100, 150, 200);
+
+    ASSERT_EQ(100, last_r);
+    ASSERT_EQ(150, last_g);
+    ASSERT_EQ(200, last_b);
+    ASSERT_EQ(0x1234, result);
+
+    PASS();
+}
+
+SUITE(color_suite) {
+    SET_SETUP(setup_callback, NULL);
+    RUN_TEST(test_color_default_black);
+    RUN_TEST(test_color_default_white);
+    RUN_TEST(test_color_fallback_arbitrary);
+    RUN_TEST(test_color_delegates_to_surface);
+}
+
+GREATEST_MAIN_DEFS();
+
+int main(int argc, char **argv) {
+    GREATEST_MAIN_BEGIN();
+    RUN_SUITE(color_suite);
+    GREATEST_MAIN_END();
+}