[gnome-shell-extensions/wip/cxiong/handle-locale-changes] Reload specials when XDG user dirs changes

[Florian Müllner <fmuellner src gnome org>]

commit 9a5b35a6b889d7c3afb85f9c40560ea5cd91e1fc
Author: Carl Xiong <xiongc05 gmail com>
Date:   Tue Mar 17 19:30:13 2015 +0800

    Reload specials when XDG user dirs changes
    
    Fixes https://gitlab.gnome.org/GNOME/gnome-shell-extensions/issues/12

 extensions/places-menu/placeDisplay.js | 38 ++++++++++++++++++++++++++++++++++
 1 file changed, 38 insertions(+)
---
diff --git a/extensions/places-menu/placeDisplay.js b/extensions/places-menu/placeDisplay.js
index ba316bf..964e0b6 100644
--- a/extensions/places-menu/placeDisplay.js
+++ b/extensions/places-menu/placeDisplay.js
@@ -235,6 +235,28 @@ var PlacesManager = new Lang.Class({
         this._showDesktopIconsChangedId =
             this._settings.connect('changed::show-desktop-icons',
                                    Lang.bind(this, this._updateSpecials));
+
+        // unlike bookmark file, XDG's 'user-dirs.dirs' here only serves as a
+        // signal gnerator: when 'reload_user_special_dirs_cache' should be
+        // invoked, not a definitive source for user special dirs, which is
+        // handled by GLib as before.
+        this._userDirsFile = this._findUserDirsFile();
+        this._userDirsTimeoutId = 0;
+        this._userDirsMonitor = null;
+
+        if (this._userDirsFile) {
+            this._userDirsMonitor = this._userDirsFile.monitor_file(Gio.FileMonitorFlags.NONE, null);
+            this._userDirsMonitor.connect('changed', Lang.bind(this, function () {
+                if (this._userDirsTimeoutId > 0)
+                    return;
+                /* Defensive event compression */
+                this._userDirsTimeoutId = Mainloop.timeout_add(100, Lang.bind(this, function () {
+                    this._userDirsTimeoutId = 0;
+                    this._updateSpecials();
+                    return false;
+                }));
+            }));
+        }
         this._updateSpecials();
 
         /*
@@ -308,6 +330,9 @@ var PlacesManager = new Lang.Class({
         if (this._settings.get_boolean('show-desktop-icons'))
             dirs.push(GLib.UserDirectory.DIRECTORY_DESKTOP);
 
+        // Reload cache s.t. the changes on disk would appear here immediately
+        GLib.reload_user_special_dirs_cache();
+
         for (let i = 0; i < dirs.length; i++) {
             let specialPath = GLib.get_user_special_dir(dirs[i]);
             if (specialPath == null || specialPath == homePath)
@@ -414,6 +439,19 @@ var PlacesManager = new Lang.Class({
         this.emit('network-updated');
     },
 
+    _findUserDirsFile: function() {
+        let paths = [
+            GLib.build_filenamev([GLib.get_user_config_dir(), 'user-dirs.dirs']),
+        ];
+
+        for (let i = 0; i < paths.length; i++) {
+            if (GLib.file_test(paths[i], GLib.FileTest.EXISTS))
+                return Gio.File.new_for_path(paths[i]);
+        }
+
+        return null;
+    },
+
     _findBookmarksFile: function() {
         let paths = [
             GLib.build_filenamev([GLib.get_user_config_dir(), 'gtk-3.0', 'bookmarks']),