[gtk/matthiasc/for-master] testsuite: Improve coverage for GdkTexture

[Matthias Clasen <matthiasc src gnome org>]

commit 1334d205caa4d2819c7450b60405cb3dcf0def3a
Author: Matthias Clasen <mclasen redhat com>
Date:   Sat Oct 31 20:51:23 2020 -0400

    testsuite: Improve coverage for GdkTexture

 testsuite/gdk/meson.build |   1 +
 testsuite/gdk/texture.c   | 120 ++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 121 insertions(+)
---
diff --git a/testsuite/gdk/meson.build b/testsuite/gdk/meson.build
index 008b6269a2..c62c931905 100644
--- a/testsuite/gdk/meson.build
+++ b/testsuite/gdk/meson.build
@@ -13,6 +13,7 @@ tests = [
   'rectangle',
   'rgba',
   'seat',
+  'texture',
 ]
 
 foreach t : tests
diff --git a/testsuite/gdk/texture.c b/testsuite/gdk/texture.c
new file mode 100644
index 0000000000..fc1f728c7c
--- /dev/null
+++ b/testsuite/gdk/texture.c
@@ -0,0 +1,120 @@
+#include <gtk.h>
+
+static gboolean
+compare_pixels (int     width,
+                int     height,
+                guchar *data1,
+                gsize   stride1,
+                guchar *data2,
+                gsize   stride2)
+{
+  int i;
+  for (i = 0; i < height; i++)
+    {
+      gconstpointer p1 = data1 + i * stride1;
+      gconstpointer p2 = data2 + i * stride2;
+      if (memcmp (p1, p2, width * 4) != 0)
+        return FALSE;
+    }
+  return TRUE;
+}
+
+static void
+test_texture_from_pixbuf (void)
+{
+  GdkPixbuf *pixbuf;
+  GdkTexture *texture;
+  GError *error = NULL;
+  guchar *data;
+  int width, height;
+  gsize stride;
+  cairo_surface_t *surface;
+  cairo_t *cr;
+
+  pixbuf = gdk_pixbuf_new_from_resource ("/org/gtk/libgtk/icons/16x16/places/user-trash.png", &error);
+  g_assert_no_error (error);
+  g_assert_nonnull (pixbuf);
+  g_assert_true (gdk_pixbuf_get_has_alpha (pixbuf));
+
+  width = gdk_pixbuf_get_width (pixbuf);
+  height = gdk_pixbuf_get_height (pixbuf);
+
+  texture = gdk_texture_new_for_pixbuf (pixbuf);
+
+  g_assert_nonnull (texture);
+  g_assert_cmpint (gdk_texture_get_width (texture), ==, width);
+  g_assert_cmpint (gdk_texture_get_height (texture), ==, height);
+
+  stride = 4 * width;
+  data = g_new0 (guchar, stride * height);
+  gdk_texture_download (texture, data, stride);
+
+  surface = cairo_image_surface_create (CAIRO_FORMAT_ARGB32, width, height);
+  cr = cairo_create (surface);
+  gdk_cairo_set_source_pixbuf (cr, pixbuf, 0, 0);
+  cairo_paint (cr);
+  cairo_destroy (cr);
+
+  g_assert_true (compare_pixels (width, height,
+                                 data, stride,
+                                 cairo_image_surface_get_data (surface),
+                                 cairo_image_surface_get_stride (surface)));
+
+  g_free (data);
+
+  g_object_unref (pixbuf);
+  g_object_unref (texture);
+  cairo_surface_destroy (surface);
+}
+
+static void
+test_texture_from_resource (void)
+{
+  GdkTexture *texture;
+  int width, height;
+
+  texture = gdk_texture_new_from_resource ("/org/gtk/libgtk/icons/16x16/places/user-trash.png");
+
+  g_assert_nonnull (texture);
+  g_object_get (texture,
+                "width", &width,
+                "height", &height,
+                NULL);
+  g_assert_cmpint (width, ==, 16);
+  g_assert_cmpint (height, ==, 16);
+
+  g_object_unref (texture);
+}
+
+static void
+test_texture_save_to_png (void)
+{
+  GdkTexture *texture;
+  GError *error = NULL;
+  GFile *file;
+  GdkTexture *texture2;
+
+  texture = gdk_texture_new_from_resource ("/org/gtk/libgtk/icons/16x16/places/user-trash.png");
+
+  gdk_texture_save_to_png (texture, "test.png");
+  file = g_file_new_for_path ("test.png");
+  texture2 = gdk_texture_new_from_file (file, &error);
+  g_object_unref (file);
+  g_assert_no_error (error);
+
+  g_object_unref (texture);
+  g_object_unref (texture2);
+}
+
+int
+main (int argc, char *argv[])
+{
+  /* We want to use resources from libgtk, so we need gtk initialized */
+  gtk_test_init (&argc, &argv, NULL);
+
+  g_test_add_func ("/texture/from-pixbuf", test_texture_from_pixbuf);
+  g_test_add_func ("/texture/from-resource", test_texture_from_resource);
+  g_test_add_func ("/texture/save-to-png", test_texture_save_to_png);
+
+  return g_test_run ();
+}