tests: Add shot test for pointer cursor behavior

Add a regression test to verify that the cursor image is correctly
updated when setting a cursor surface with an already committed buffer
from a previous pointer entry, without recommitting a cursor buffer for
the current entry.

Signed-off-by: Alexandros Frantzis <alexandros.frantzis@collabora.com>

tests/meson.build

@@ -158,6 +158,7 @@ tests = [
 			input_timestamps_unstable_v1_protocol_c,
 		],
 	},
+	{	'name': 'pointer-shot', },
 	{
 		'name': 'presentation',
 		'sources': [

tests/pointer-shot-test.c

@@ -0,0 +1,175 @@
+/*
+ * Copyright 2021 Collabora Ltd
+ *
+ * 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 (including the
+ * next paragraph) 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.
+ */
+
+#include "config.h"
+
+#include <stdio.h>
+#include <string.h>
+#include <sys/mman.h>
+
+#include "shared/timespec-util.h"
+#include "weston-test-client-helper.h"
+#include "weston-test-fixture-compositor.h"
+
+struct setup_args {
+	struct fixture_metadata meta;
+	enum renderer_type renderer;
+};
+
+static const struct setup_args my_setup_args[] = {
+	{
+		.renderer = RENDERER_PIXMAN,
+		.meta.name = "pixman"
+	},
+	{
+		.renderer = RENDERER_GL,
+		.meta.name = "GL"
+	},
+};
+
+static enum test_result_code
+fixture_setup(struct weston_test_harness *harness, const struct setup_args *arg)
+{
+	struct compositor_setup setup;
+
+	compositor_setup_defaults(&setup);
+	setup.renderer = arg->renderer;
+	setup.width = 320;
+	setup.height = 240;
+	setup.shell = SHELL_TEST_DESKTOP;
+
+	return weston_test_harness_execute_as_client(harness, &setup);
+}
+DECLARE_FIXTURE_SETUP_WITH_ARG(fixture_setup, my_setup_args, meta);
+
+static const struct timespec t0 = { .tv_sec = 0, .tv_nsec = 0 };
+static const struct timespec t1 = { .tv_sec = 1, .tv_nsec = 0 };
+static const struct timespec t2 = { .tv_sec = 2, .tv_nsec = 0 };
+static const struct timespec t3 = { .tv_sec = 3, .tv_nsec = 0 };
+
+static void
+send_motion(struct client *client, const struct timespec *time, int x, int y)
+{
+	uint32_t tv_sec_hi, tv_sec_lo, tv_nsec;
+
+	timespec_to_proto(time, &tv_sec_hi, &tv_sec_lo, &tv_nsec);
+	weston_test_move_pointer(client->test->weston_test, tv_sec_hi, tv_sec_lo,
+				 tv_nsec, x, y);
+	client_roundtrip(client);
+}
+
+static struct buffer *
+surface_commit_color(struct client *client, struct wl_surface *surface,
+		     pixman_color_t *color, int width, int height)
+{
+	struct buffer *buf;
+
+	buf = create_shm_buffer_a8r8g8b8(client, width, height);
+	fill_image_with_color(buf->image, color);
+	wl_surface_attach(surface, buf->proxy, 0, 0);
+	wl_surface_damage(surface, 0, 0, width, height);
+	wl_surface_commit(surface);
+
+	return buf;
+}
+
+TEST(pointer_cursor_retains_committed_buffer_after_reenter)
+{
+	struct client *client;
+	pixman_color_t red;
+	pixman_color_t green;
+	pixman_color_t gray;
+	pixman_color_t magenta;
+	bool match;
+	struct surface *main_surface;
+	struct surface *back_surface;
+	struct surface *main_cursor_surface;
+	struct surface *back_cursor_surface;
+
+	color_rgb888(&red, 255, 0, 0);
+	color_rgb888(&green, 0, 255, 0);
+	color_rgb888(&gray, 127, 127, 127);
+	color_rgb888(&magenta, 255, 0, 255);
+
+	client = create_client();
+
+	/* Move the cursor out of the way of the main surface */
+	send_motion(client, &t0, 0, 0);
+
+	/* Create all surfaces. */
+	main_surface = create_test_surface(client);
+	back_surface = create_test_surface(client);
+	main_cursor_surface = create_test_surface(client);
+	back_cursor_surface = create_test_surface(client);
+
+	/* Commit buffers for cursors. */
+	surface_commit_color(client, main_cursor_surface->wl_surface, &green, 25, 25);
+	surface_commit_color(client, back_cursor_surface->wl_surface, &magenta, 25, 25);
+
+	/* We need our own background surface so that we are able to change the cursor
+	 * when the pointer leaves the main surface.
+	 */
+	weston_test_move_surface(client->test->weston_test, back_surface->wl_surface, 0, 0);
+	surface_commit_color(client, back_surface->wl_surface, &gray, 320, 240);
+
+	/* Set up the main surface. */
+	client->surface = main_surface;
+	client->surface->buffer = create_shm_buffer_a8r8g8b8(client, 100, 100);
+	fill_image_with_color(client->surface->buffer->image, &red);
+	move_client(client, 50, 50);
+
+	/* Move the pointer into the main surface. */
+	send_motion(client, &t1, 100, 100);
+	wl_pointer_set_cursor(client->input->pointer->wl_pointer,
+			      client->input->pointer->serial,
+			      main_cursor_surface->wl_surface, 0, 0);
+	match = verify_screen_content(client, "pointer_cursor_reenter", 0,
+				      NULL, 0);
+	assert(match);
+
+	/* Move the cursor just outside the main surface. */
+	send_motion(client, &t2, 150, 150);
+	wl_pointer_set_cursor(client->input->pointer->wl_pointer,
+			      client->input->pointer->serial,
+			      back_cursor_surface->wl_surface, 0, 0);
+	match = verify_screen_content(client, "pointer_cursor_reenter", 1,
+				      NULL, 1);
+	assert(match);
+
+	/* And back in the main surface again. */
+	send_motion(client, &t3, 149, 149);
+	wl_pointer_set_cursor(client->input->pointer->wl_pointer,
+			      client->input->pointer->serial,
+			      main_cursor_surface->wl_surface, 0, 0);
+	match = verify_screen_content(client, "pointer_cursor_reenter", 2,
+				      NULL, 2);
+	assert(match);
+
+	surface_destroy(back_cursor_surface);
+	surface_destroy(main_cursor_surface);
+	surface_destroy(back_surface);
+	/* main_surface is destroyed when destroying the client. */
+	client_destroy(client);
+}