[gnome-shell] gdm: Keep messages in queue until we've not fully processed them

[Marge Bot <marge-bot src gnome org>]

commit ef10bb6229ceb323822f27a436c5f3ce9ba12696
Author: Marco Trevisan (Treviño) <mail 3v1n0 net>
Date:   Tue Feb 16 02:00:41 2021 +0100

    gdm: Keep messages in queue until we've not fully processed them
    
    It can be convenient to get the currently showing message in order to
    replace or remove it in case it's not needed anymore.
    
    So simplify the message queue handling by only depending on a single
    local variable (_messageQueue) and redefining hasPendingMessages
    depending on its content.
    
    Now messages are kept in queue till they are not fully processed and the
    first message is always the one currently shown.
    
    Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/1683>

 js/gdm/util.js | 36 +++++++++++++++++++++---------------
 1 file changed, 21 insertions(+), 15 deletions(-)
---
diff --git a/js/gdm/util.js b/js/gdm/util.js
index 369c0bb331..16689f10e6 100644
--- a/js/gdm/util.js
+++ b/js/gdm/util.js
@@ -172,7 +172,6 @@ var ShellUserVerifier = class {
 
         this._messageQueue = [];
         this._messageQueueTimeoutId = 0;
-        this.hasPendingMessages = false;
         this.reauthenticating = false;
 
         this._failCounter = 0;
@@ -194,10 +193,18 @@ var ShellUserVerifier = class {
         }
     }
 
+    get hasPendingMessages() {
+        return !!this._messageQueue.length;
+    }
+
     get allowedFailures() {
         return this._settings.get_int(ALLOWED_FAILURES_KEY);
     }
 
+    get currentMessage() {
+        return this._messageQueue ? this._messageQueue[0] : null;
+    }
+
     begin(userName, hold) {
         this._cancellable = new Gio.Cancellable();
         this._hold = hold;
@@ -283,7 +290,6 @@ var ShellUserVerifier = class {
 
         this._messageQueue = [];
 
-        this.hasPendingMessages = false;
         this.emit('no-more-messages');
     }
 
@@ -293,33 +299,33 @@ var ShellUserVerifier = class {
     }
 
     _queueMessageTimeout() {
-        if (this._messageQueue.length == 0) {
-            this.finishMessageQueue();
-            return;
-        }
-
         if (this._messageQueueTimeoutId != 0)
             return;
 
-        let message = this._messageQueue.shift();
+        const message = this.currentMessage;
 
         delete this._currentMessageExtraInterval;
         this.emit('show-message', message.serviceName, message.text, message.type);
 
         this._messageQueueTimeoutId = GLib.timeout_add(GLib.PRIORITY_DEFAULT,
-            message.interval + (this._currentMessageExtraInterval | 0),
-                                                       () => {
-                                                           this._messageQueueTimeoutId = 0;
-                                                           this._queueMessageTimeout();
-                                                           return GLib.SOURCE_REMOVE;
-                                                       });
+            message.interval + (this._currentMessageExtraInterval | 0), () => {
+                this._messageQueueTimeoutId = 0;
+
+                if (this._messageQueue.length > 1) {
+                    this._messageQueue.shift();
+                    this._queueMessageTimeout();
+                } else {
+                    this.finishMessageQueue();
+                }
+
+                return GLib.SOURCE_REMOVE;
+            });
         GLib.Source.set_name_by_id(this._messageQueueTimeoutId, '[gnome-shell] this._queueMessageTimeout');
     }
 
     _queueMessage(serviceName, message, messageType) {
         let interval = this._getIntervalForMessage(message);
 
-        this.hasPendingMessages = true;
         this._messageQueue.push({ serviceName, text: message, type: messageType, interval });
         this._queueMessageTimeout();
     }