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

[Florian Müllner <fmuellner src gnome org>]

commit 69424df8ffc15ff1355b7fbec0e8cd3da098119a
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).

 js/ui/shellDBus.js | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)
---
diff --git a/js/ui/shellDBus.js b/js/ui/shellDBus.js
index aeabe6d81e..39bba7aa34 100644
--- a/js/ui/shellDBus.js
+++ b/js/ui/shellDBus.js
@@ -1,7 +1,7 @@
 // -*- mode: js; js-indent-level: 4; indent-tabs-mode: nil -*-
 /* exported GnomeShell, ScreenSaverDBus */
 
-const { Gio, GLib, Meta } = imports.gi;
+const { Gio, GLib, Meta, Shell } = imports.gi;
 
 const Config = imports.misc.config;
 const ExtensionDownloader = imports.ui.extensionDownloader;
@@ -153,6 +153,15 @@ var GnomeShell = class {
             return;
         }
 
+        const 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;
+        }
+
         Main.overview.selectApp(id);
         invocation.return_value(null);
     }