Check pixbuf loader signals

This test will detect the problem noted in aruiz#73.

tests/meson.build

@@ -10,6 +10,7 @@ t_null_error = executable('t_null_error',  't_null_error.c', dependencies : [gdk
 t_scaled     = executable('t_scaled',      't_scaled.c',     dependencies : [gdkpb, webp, webpdemux])
 t_jpeg       = executable('t_jpeg',        't_jpeg.c',       dependencies : [gdkpb, webp, webpdemux])
 t_large      = executable('t_large',       't_large.c',      dependencies : [gdkpb, webp, webpdemux, gio])
+t_signals    = executable('t_signals',     't_signals.c',    dependencies : [gdkpb, webp, webpdemux, gio])
 
 loaders_data = configuration_data()
 loaders_data.set('MODULE_PATH', fs.as_posix(pbl_webp.full_path()))
@@ -29,4 +30,5 @@ test('icc data',           t_icc, env : test_env + [ test_file_base / 't2.webp']
 test('NULL GError', t_null_error, env : test_env + [ test_file_base / 't2.webp'])
 test('large file',       t_large, env : test_env + [ test_file_base / 't_large.webp'])
 test('scaled image',    t_scaled, env : test_env + [ test_file_base / 't2.webp', 'TEST_FILE_ANIM=' + meson.current_source_dir() / 'data' / 't3.webp'])
-test('jpeg with .webp extension', t_jpeg, env : test_env + [ test_file_base / 'test_jpeg_as_webp.webp'])
+test('jpeg with .webp extension', t_jpeg, env : test_env + [ test_file_base / 'test_jpeg_as_webp.webp'])
+test('signal handling',    t_signals, env : test_env + [ test_file_base / 't2.webp'])

tests/t_signals.c

@@ -0,0 +1,83 @@
+#include <gdk-pixbuf/gdk-pixbuf.h>
+
+gint area_prepared_cb_count = 0;
+gint area_updated_cb_count = 0;
+gint closed_cb_count = 0;
+gint size_prepared_cb_count = 0;
+
+void
+area_prepared_cb (GdkPixbufLoader* self, gpointer user_data)
+{
+  area_prepared_cb_count++;
+}
+
+void
+area_updated_cb (GdkPixbufLoader* self, gint x, gint y, gint width, gint height, gpointer user_data)
+{
+  area_updated_cb_count++;
+
+  g_assert_cmpint (x, ==, 0);
+  g_assert_cmpint (y, ==, 0);
+  g_assert_cmpint (width, ==, 200);
+  g_assert_cmpint (height, ==, 200);
+}
+
+void
+closed_cb (GdkPixbufLoader* self, gpointer user_data)
+{
+  closed_cb_count++;
+}
+
+void
+size_prepared_cb (GdkPixbufLoader* self, gint width, gint height, gpointer user_data)
+{
+  size_prepared_cb_count++;
+
+  g_assert_cmpint (width, ==, 200);
+  g_assert_cmpint (height, ==, 200);
+}
+
+gint
+main (gint argc, gchar **argv)
+{
+  gchar **env   = g_get_environ ();
+  GdkPixbufLoader *loader;
+  GError *error = NULL;
+  gsize pixbuf_size;
+  guchar *pixbuf_data;
+
+  loader = gdk_pixbuf_loader_new();
+
+  g_signal_connect (G_OBJECT(loader), "area-prepared", G_CALLBACK(area_prepared_cb), NULL);
+  g_signal_connect (G_OBJECT(loader), "area-updated", G_CALLBACK(area_updated_cb), NULL);
+  g_signal_connect (G_OBJECT(loader), "closed", G_CALLBACK(closed_cb), NULL);
+  g_signal_connect (G_OBJECT(loader), "size-prepared", G_CALLBACK(size_prepared_cb), NULL);
+
+  g_file_get_contents (g_environ_getenv (env, "TEST_FILE"), (gchar**)&pixbuf_data, &pixbuf_size, &error);
+  if (error)
+    g_error ("%s", error->message);
+  g_assert (error == NULL);
+
+  gdk_pixbuf_loader_write(loader, pixbuf_data, pixbuf_size, &error);
+  if (error)
+    g_error ("%s", error->message);
+  g_assert (error == NULL);
+
+  g_free(pixbuf_data);
+
+  gdk_pixbuf_loader_close(loader, &error);
+  if (error)
+    g_error ("%s", error->message);
+  g_assert (error == NULL);
+
+  g_object_unref(G_OBJECT(loader));
+
+  g_strfreev (env);
+
+  g_assert_cmpint (area_prepared_cb_count, ==, 1);
+  g_assert_cmpint (area_updated_cb_count, ==, 1);
+  g_assert_cmpint (closed_cb_count, ==, 1);
+  g_assert_cmpint (size_prepared_cb_count, ==, 1);
+
+  return 0;
+}