[gnome-shell/wip/fmuellner/focus-app-error] shellDBus: Return error on invalid app IDs

[Florian Müllner <fmuellner src gnome org>]

commit 078a1bda1414c6bb4565b294f0b8f0a7025b85f0
Author: Florian Müllner <fmuellner gnome org>
Date:   Tue Jan 8 22:03:13 2019 +0100

    shellDBus: Return error on invalid app IDs
    
    When passing an invalid or unknown app ID to FocusApp(), we currently
    open the app picker and silently fail to select the desired app.
    Instead of half-working like that, make it clear that the argument
    was invalid by returning an appropriate error. (It's easy to get the
    ID wrong, as unlike appstream/flatpak IDs, we include the ".desktop"
    suffix).
    
    https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/337

 js/ui/shellDBus.js | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)
---
diff --git a/js/ui/shellDBus.js b/js/ui/shellDBus.js
index a200a1bdd..c1d604fa2 100644
--- a/js/ui/shellDBus.js
+++ b/js/ui/shellDBus.js
@@ -101,9 +101,20 @@ var GnomeShell = new Lang.Class({
         Main.osdWindowManager.show(monitorIndex, icon, label, level, maxLevel);
     },
 
-    FocusApp(id) {
+    FocusAppAsync(params, invocation) {
+        let [id] = params;
+        let appSys = Shell.AppSystem.get_default();
+        if (appSys.lookup_app(id) == null) {
+            invocation.return_error_literal(
+                Gio.DBusError,
+                Gio.DBusError.FILE_NOT_FOUND,
+                `No application with ID ${id}`);
+            return;
+        }
+
         this.ShowApplications();
         Main.overview.viewSelector.appDisplay.selectApp(id);
+        invocation.return_value(null);
     },
 
     ShowApplications() {