[gnome-software] shell: Improve the error message when whole update operation fails

[Kalev Lember <klember src gnome org>]

commit 6c785cc08fdbcec07556b9a5e53ffa6c7bd55909
Author: Kalev Lember <klember redhat com>
Date:   Tue Jan 15 23:48:33 2019 +0100

    shell: Improve the error message when whole update operation fails
    
    In case the whole updates operation fails and we don't have the data
    which app failed, show 'Unable to install updates' error instead of
    'Unable to update "(null)"'.
    
    Fixes: https://gitlab.gnome.org/GNOME/gnome-software/issues/480

 src/gs-shell.c | 120 +++++++++++++++++++++++++++++++++++++++++----------------
 1 file changed, 87 insertions(+), 33 deletions(-)
---
diff --git a/src/gs-shell.c b/src/gs-shell.c
index 03aeba9c..1110b1bc 100644
--- a/src/gs-shell.c
+++ b/src/gs-shell.c
@@ -1293,23 +1293,34 @@ gs_shell_show_event_update (GsShell *shell, GsPluginEvent *event)
        g_autofree gchar *str_origin = NULL;
        g_autoptr(GString) str = g_string_new (NULL);
 
-       str_app = gs_shell_get_title_from_app (app);
        switch (error->code) {
        case GS_PLUGIN_ERROR_DOWNLOAD_FAILED:
-               if (origin != NULL) {
+               if (app != NULL && origin != NULL) {
+                       str_app = gs_shell_get_title_from_app (app);
                        str_origin = gs_shell_get_title_from_origin (origin);
                        /* TRANSLATORS: failure text for the in-app notification,
                         * where the first %s is the app name (e.g. "GIMP") and
                         * the second %s is the origin, e.g. "Fedora" or
                         * "Fedora Project [fedoraproject.org]" */
-                       g_string_append_printf (str, _("Unable to update %s from %s"),
+                       g_string_append_printf (str, _("Unable to update %s from %s as download failed"),
                                               str_app, str_origin);
                        buttons = TRUE;
-               } else {
+               } else if (app != NULL) {
+                       str_app = gs_shell_get_title_from_app (app);
                        /* TRANSLATORS: failure text for the in-app notification,
                         * where the %s is the application name (e.g. "GIMP") */
                        g_string_append_printf (str, _("Unable to update %s as download failed"),
                                                str_app);
+               } else if (origin != NULL) {
+                       str_origin = gs_shell_get_title_from_origin (origin);
+                       /* TRANSLATORS: failure text for the in-app notification,
+                        * where the %s is the origin, e.g. "Fedora" or
+                        * "Fedora Project [fedoraproject.org]" */
+                       g_string_append_printf (str, _("Unable to install updates from %s as download 
failed"),
+                                               str_origin);
+               } else {
+                       /* TRANSLATORS: failure text for the in-app notification */
+                       g_string_append_printf (str, _("Unable to install updates as download failed"));
                }
                break;
        case GS_PLUGIN_ERROR_NO_NETWORK:
@@ -1320,48 +1331,91 @@ gs_shell_show_event_update (GsShell *shell, GsPluginEvent *event)
                buttons |= GS_SHELL_EVENT_BUTTON_NETWORK_SETTINGS;
                break;
        case GS_PLUGIN_ERROR_NO_SPACE:
-               /* TRANSLATORS: failure text for the in-app notification,
-                * where the %s is the application name (e.g. "GIMP") */
-               g_string_append_printf (str, _("Unable to update %s: "
-                                              "not enough disk space"),
-                                       str_app);
+               if (app != NULL) {
+                       str_app = gs_shell_get_title_from_app (app);
+                       /* TRANSLATORS: failure text for the in-app notification,
+                        * where the %s is the application name (e.g. "GIMP") */
+                       g_string_append_printf (str, _("Unable to update %s: "
+                                                      "not enough disk space"),
+                                               str_app);
+               } else {
+                       /* TRANSLATORS: failure text for the in-app notification */
+                       g_string_append_printf (str, _("Unable to install updates: "
+                                                      "not enough disk space"));
+               }
                buttons |= GS_SHELL_EVENT_BUTTON_NO_SPACE;
                break;
        case GS_PLUGIN_ERROR_AUTH_REQUIRED:
-               /* TRANSLATORS: failure text for the in-app notification,
-                * where the %s is the application name (e.g. "GIMP") */
-               g_string_append_printf (str, _("Unable to update %s: "
-                                              "authentication was required"),
-                                       str_app);
+               if (app != NULL) {
+                       str_app = gs_shell_get_title_from_app (app);
+                       /* TRANSLATORS: failure text for the in-app notification,
+                        * where the %s is the application name (e.g. "GIMP") */
+                       g_string_append_printf (str, _("Unable to update %s: "
+                                                      "authentication was required"),
+                                               str_app);
+               } else {
+                       /* TRANSLATORS: failure text for the in-app notification */
+                       g_string_append_printf (str, _("Unable to install updates: "
+                                                      "authentication was required"));
+               }
                break;
        case GS_PLUGIN_ERROR_AUTH_INVALID:
-               /* TRANSLATORS: failure text for the in-app notification,
-                * where the %s is the application name (e.g. "GIMP") */
-               g_string_append_printf (str, _("Unable to update %s: "
-                                              "authentication was invalid"),
-                                       str_app);
+               if (app != NULL) {
+                       str_app = gs_shell_get_title_from_app (app);
+                       /* TRANSLATORS: failure text for the in-app notification,
+                        * where the %s is the application name (e.g. "GIMP") */
+                       g_string_append_printf (str, _("Unable to update %s: "
+                                                      "authentication was invalid"),
+                                               str_app);
+               } else {
+                       /* TRANSLATORS: failure text for the in-app notification */
+                       g_string_append_printf (str, _("Unable to install updates: "
+                                                      "authentication was invalid"));
+               }
                break;
        case GS_PLUGIN_ERROR_NO_SECURITY:
-               /* TRANSLATORS: failure text for the in-app notification,
-                * where the %s is the application name (e.g. "GIMP") */
-               g_string_append_printf (str, _("Unable to update %s: "
-                                              "you do not have permission to "
-                                              "update software"),
-                                       str_app);
+               if (app != NULL) {
+                       str_app = gs_shell_get_title_from_app (app);
+                       /* TRANSLATORS: failure text for the in-app notification,
+                        * where the %s is the application name (e.g. "GIMP") */
+                       g_string_append_printf (str, _("Unable to update %s: "
+                                                      "you do not have permission to "
+                                                      "update software"),
+                                               str_app);
+               } else {
+                       /* TRANSLATORS: failure text for the in-app notification */
+                       g_string_append_printf (str, _("Unable to install updates: "
+                                                      "you do not have permission to "
+                                                      "update software"));
+               }
                break;
        case GS_PLUGIN_ERROR_AC_POWER_REQUIRED:
-               /* TRANSLATORS: failure text for the in-app notification,
-                * where the %s is the application name (e.g. "Dell XPS 13") */
-               g_string_append_printf (str, _("Unable to update %s: "
-                                              "AC power is required"),
-                                       str_app);
+               if (app != NULL) {
+                       str_app = gs_shell_get_title_from_app (app);
+                       /* TRANSLATORS: failure text for the in-app notification,
+                        * where the %s is the application name (e.g. "Dell XPS 13") */
+                       g_string_append_printf (str, _("Unable to update %s: "
+                                                      "AC power is required"),
+                                               str_app);
+               } else {
+                       /* TRANSLATORS: failure text for the in-app notification,
+                        * where the %s is the application name (e.g. "Dell XPS 13") */
+                       g_string_append_printf (str, _("Unable to install updates: "
+                                                      "AC power is required"));
+               }
                break;
        case GS_PLUGIN_ERROR_CANCELLED:
                break;
        default:
-               /* TRANSLATORS: failure text for the in-app notification,
-                * where the %s is the application name (e.g. "GIMP") */
-               g_string_append_printf (str, _("Unable to update %s"), str_app);
+               if (app != NULL) {
+                       str_app = gs_shell_get_title_from_app (app);
+                       /* TRANSLATORS: failure text for the in-app notification,
+                        * where the %s is the application name (e.g. "GIMP") */
+                       g_string_append_printf (str, _("Unable to update %s"), str_app);
+               } else {
+                       /* TRANSLATORS: failure text for the in-app notification */
+                       g_string_append_printf (str, _("Unable to install updates"));
+               }
                break;
        }
        if (str->len == 0)