gdesktopappinfo: Take in account the desktop Path to find executables

Desktop files can provide the executable working path and that can be
used to pick the file to launch.

So take it in account.

gio/tests/appinfo-test-path.desktop.in

@@ -0,0 +1,22 @@
+[Desktop Entry]
+Type=Application
+GenericName=generic-appinfo-test-path
+Name=appinfo-test-path
+Name[de]=appinfo-test-de
+X-GNOME-FullName=example
+X-GNOME-FullName[de]=Beispiel
+Comment=GAppInfo example
+Comment[de]=GAppInfo Beispiel
+Path=@installed_tests_dir@
+TryExec=apps
+Exec=appinfo-test --option %U %i --name %c --filename %k %m %%
+Icon=testicon.svg
+Terminal=false
+StartupNotify=true
+StartupWMClass=appinfo-path-class
+MimeType=image/png;image/jpeg;
+Keywords=keyword1;test keyword;
+Categories=GNOME;GTK;
+X-JunkFood=Burger
+X-JunkFood[de]=Bratwurst
+X-JunkFood[it]=

gio/tests/desktop-app-info.c

@@ -1578,6 +1578,64 @@ test_launch_uris_with_invalid_terminal (void)
   g_free (old_path);
 }
 
+static void
+test_app_path (void)
+{
+  GDesktopAppInfo *appinfo;
+  const char *desktop_path;
+
+  desktop_path = g_test_get_filename (G_TEST_BUILT, "appinfo-test-path.desktop", NULL);
+  appinfo = g_desktop_app_info_new_from_filename (desktop_path);
+
+  g_assert_true (G_IS_DESKTOP_APP_INFO (appinfo));
+
+  g_clear_object (&appinfo);
+}
+
+static void
+test_app_path_wrong (void)
+{
+  GKeyFile *key_file;
+  GDesktopAppInfo *appinfo;
+  const gchar bad_try_exec_file_contents[] =
+    "[Desktop Entry]\n"
+    "Type=Application\n"
+    "Name=appinfo-test\n"
+    "TryExec=appinfo-test\n"
+    "Path=this-must-not-exist‼\n"
+    "Exec=true\n";
+  const gchar bad_exec_file_contents[] =
+    "[Desktop Entry]\n"
+    "Type=Application\n"
+    "Name=appinfo-test\n"
+    "TryExec=true\n"
+    "Path=this-must-not-exist‼\n"
+    "Exec=appinfo-test\n";
+
+  g_assert_true (
+    g_file_test (g_test_get_filename (G_TEST_BUILT, "appinfo-test", NULL),
+      G_FILE_TEST_IS_REGULAR | G_FILE_TEST_IS_EXECUTABLE));
+
+  key_file = g_key_file_new ();
+
+  g_assert_true (
+    g_key_file_load_from_data (key_file, bad_try_exec_file_contents, -1,
+                               G_KEY_FILE_NONE, NULL));
+
+  appinfo = g_desktop_app_info_new_from_keyfile (key_file);
+  g_assert_false (G_IS_DESKTOP_APP_INFO (appinfo));
+
+  g_assert_true (
+    g_key_file_load_from_data (key_file, bad_exec_file_contents, -1,
+                               G_KEY_FILE_NONE, NULL));
+
+  appinfo = g_desktop_app_info_new_from_keyfile (key_file);
+  g_assert_false (G_IS_DESKTOP_APP_INFO (appinfo));
+
+  g_clear_pointer (&key_file, g_key_file_unref);
+  g_clear_object (&appinfo);
+}
+
 int
 main (int   argc,
       char *argv[])
@@ -1615,6 +1673,8 @@ main (int   argc,
   g_test_add_func ("/desktop-app-info/search", test_search);
   g_test_add_func ("/desktop-app-info/implements", test_implements);
   g_test_add_func ("/desktop-app-info/show-in", test_show_in);
+  g_test_add_func ("/desktop-app-info/app-path", test_app_path);
+  g_test_add_func ("/desktop-app-info/app-path/wrong", test_app_path_wrong);
   g_test_add_func ("/desktop-app-info/launch-as-manager", test_launch_as_manager);
   g_test_add_func ("/desktop-app-info/launch-as-manager/fail", test_launch_as_manager_fail);
   g_test_add_func ("/desktop-app-info/launch-default-uri-handler", test_default_uri_handler);

gio/tests/meson.build

@@ -628,6 +628,7 @@ endif
 appinfo_test_desktop_files = [
   'appinfo-test-gnome',
   'appinfo-test-notgnome',
+  'appinfo-test-path',
   'appinfo-test',
   'appinfo-test2',
 ]