Don't muck with prefs any more than necessary on quit. Closes issue #162.

common/content/dactyl.js

@@ -930,16 +930,17 @@ const Dactyl = Module("dactyl", {
      *    windows could be closed individually.
      */
     quit: function (saveSession, force) {
-        // TODO: Use safeSetPref?
-        if (saveSession)
-            prefs.set("browser.startup.page", 3); // start with saved session
-        else
-            prefs.set("browser.startup.page", 1); // start with default homepage session
+        if (!force && !canQuitApplication())
+            return;
 
-        if (force)
-            services.get("appStartup").quit(Ci.nsIAppStartup.eForceQuit);
-        else
-            window.goQuitApplication();
+        let pref = "browser.startup.page";
+        prefs.save(pref);
+        if (saveSession)
+            prefs.safeSet(pref, 3);
+        if (!saveSession && prefs.get(pref) >= 2)
+            prefs.safeSet(pref, 1);
+
+        services.get("appStartup").quit(Ci.nsIAppStartup[force ? "eForceQuit" : "eAttemptQuit"]);
     },
 
     /**
@@ -1044,23 +1045,10 @@ const Dactyl = Module("dactyl", {
      * Restart the host application.
      */
     restart: function () {
-        // notify all windows that an application quit has been requested.
-        var cancelQuit = Cc["@mozilla.org/supports-PRBool;1"].createInstance(Ci.nsISupportsPRBool);
-        services.get("observer").notifyObservers(cancelQuit, "quit-application-requested", null);
-
-        // something aborted the quit process.
-        if (cancelQuit.data)
+        if (!canQuitApplication())
             return;
 
-        // notify all windows that an application quit has been granted.
-        services.get("observer").notifyObservers(null, "quit-application-granted", null);
-
-        // enumerate all windows and call shutdown handlers
-        for (let win in iter(services.get("windowMediator").getEnumerator(null)))
-            if (("tryToClose" in win) && !win.tryToClose())
-                return;
-
-        services.get("appStartup").quit(Ci.nsIAppStartup.eRestart | Ci.nsIAppStartup.eAttemptQuit);
+        services.get("appStartup").quit(Ci.nsIAppStartup.eAttemptQuit | Ci.nsIAppStartup.eRestart);
     },
 
     /**
@@ -1323,11 +1311,10 @@ const Dactyl = Module("dactyl", {
             "Open the help page",
             function () { dactyl.help(); });
 
-        if (dactyl.has("session")) {
+        if (dactyl.has("session"))
             mappings.add([modes.NORMAL], ["ZQ"],
                 "Quit and don't save the session",
                 function () { dactyl.quit(false); });
-        }
 
         mappings.add([modes.NORMAL], ["ZZ"],
             "Quit and save the session",

common/modules/util.jsm

@@ -1069,6 +1069,8 @@ const Util = Module("Util", XPCOM([Ci.nsIObserver, Ci.nsISupportsWeakReference])
 
 const Prefs = Module("prefs", XPCOM([Ci.nsIObserver, Ci.nsISupportsWeakReference]), {
     SAVED: "extensions.dactyl.saved.",
+    RESTORE: "extensions.dactyl.restore.",
+
 
     init: function () {
         this._prefContexts = [];
@@ -1077,6 +1079,8 @@ const Prefs = Module("prefs", XPCOM([Ci.nsIObserver, Ci.nsISupportsWeakReference
         this._branch = services.get("pref").getBranch("").QueryInterface(Ci.nsIPrefBranch2);
         this._branch.addObserver("", this, false);
         this._observers = {};
+
+        this.restore();
     },
 
     observe: {
@@ -1153,9 +1157,7 @@ const Prefs = Module("prefs", XPCOM([Ci.nsIObserver, Ci.nsISupportsWeakReference
      * @param {value} defaultValue The value to return if the preference
      *     is unset.
      */
-    get: function (name, defaultValue) {
-        return this._load(name, defaultValue);
-    },
+    get: function (name, defaultValue) this._load(name, defaultValue),
 
     /**
      * Returns the default value of a preference
@@ -1164,9 +1166,7 @@ const Prefs = Module("prefs", XPCOM([Ci.nsIObserver, Ci.nsISupportsWeakReference
      * @param {value} defaultValue The value to return if the preference
      *     has no default value.
      */
-    getDefault:  function (name, defaultValue) {
-        return this._load(name, defaultValue, true);
-    },
+    getDefault:  function (name, defaultValue) this._load(name, defaultValue, true),
 
     /**
      * Returns the names of all preferences.
@@ -1211,10 +1211,10 @@ const Prefs = Module("prefs", XPCOM([Ci.nsIObserver, Ci.nsISupportsWeakReference
      * @param {string} name The preference name.
      * @param {value} value The new preference value.
      */
-    safeSet: function (name, value, message) {
+    safeSet: function (name, value, message, skipSave) {
         this._checkSafe(name, message, value);
         this._store(name, value);
-        this._store(this.SAVED + name, value);
+        this[skipSave ? "reset" : "_store"](this.SAVED + name, value);
     },
 
     /**
@@ -1227,6 +1227,31 @@ const Prefs = Module("prefs", XPCOM([Ci.nsIObserver, Ci.nsISupportsWeakReference
         this._store(name, value);
     },
 
+    /**
+     * Saves the current value of a preference to be restored at next
+     * startup.
+     *
+     * @param {string} name The preference to save.
+     */
+    save: function (name) {
+        let val = this.get(name);
+        this.set(this.RESTORE + name, val);
+        this.safeSet(name, val);
+    },
+
+    /**
+     * Restores saved preferences in the given branch.
+     *
+     * @param {string} branch The branch from which to restore
+     *      preferences. @optional
+     */
+    restore: function (branch) {
+        this.getNames(this.RESTORE + (branch || "")).forEach(function (pref) {
+            this.safeSet(pref.substr(this.RESTORE.length), this.get(pref), null, true)
+            this.reset(pref);
+        }, this);
+    },
+
     /**
      * Resets the preference *name* to its default value.
      *