847309 - Internal exception when an add-on whose Widget was removed by the user unloads

Status: RESOLVED WONTFIX

(Add-on SDK Graveyard :: General, defect)

Description

[u463949]

User Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:19.0) Gecko/20100101 Firefox/19.0
Build ID: 20130227155931

Steps to reproduce:

1. Install the following add-on:

var Widget = require("sdk/widget").Widget;
exports.main = function() {
  Widget({
    id: "widget-test",
    label: "widget test",
    content: "Test.",
    width: 50
  });
}

2. Remove the add-on's widget from the add-on bar by dragging it to the palette.
3. Close Firefox


Actual results:

Internal exceptions in the SDK:

====================

error: widget: An exception occurred.
TypeError: this._symbiont is null
resource://jid1-izhfvv5cr1cgdg-at-jetpack/addon-sdk/lib/sdk/widget.js 929
Traceback (most recent call last):
  File "resource://jid1-izhfvv5cr1cgdg-at-jetpack/addon-sdk/lib/sdk/deprecated/errors.js", line 23, in 
    return callback.apply(this, arguments);
  File "resource://jid1-izhfvv5cr1cgdg-at-jetpack/addon-sdk/lib/sdk/deprecated/window-utils.js", line 123, in observe
    this._unregWindow(window);
  File "resource://jid1-izhfvv5cr1cgdg-at-jetpack/addon-sdk/lib/sdk/deprecated/window-utils.js", line 98, in _unregWindow
    this._delegate.onUntrack(window);
  File "resource://jid1-izhfvv5cr1cgdg-at-jetpack/addon-sdk/lib/sdk/widget.js", line 521, in browserManager_onUntrack
    this.items.forEach(function(i) i._onWindowClosed(window));
  File "resource://jid1-izhfvv5cr1cgdg-at-jetpack/addon-sdk/lib/sdk/widget.js", line 521, in 
    this.items.forEach(function(i) i._onWindowClosed(window));
  File "resource://jid1-izhfvv5cr1cgdg-at-jetpack/addon-sdk/lib/sdk/widget.js", line 309, in _onWindowClosed
    view.destroy();
  File "resource://jid1-izhfvv5cr1cgdg-at-jetpack/addon-sdk/lib/sdk/widget.js", line 470, in WidgetView_destroy
    this._chrome.destroy();
  File "resource://jid1-izhfvv5cr1cgdg-at-jetpack/addon-sdk/lib/sdk/widget.js", line 929, in WC_destroy
    this._symbiont.destroy();
error: widget: An exception occurred.
TypeError: this.node.parentNode is null
resource://jid1-izhfvv5cr1cgdg-at-jetpack/addon-sdk/lib/sdk/widget.js 927
Traceback (most recent call last):
  File "resource://gre/modules/XPIProvider.jsm", line 1685, in shutdownObserver
    BOOTSTRAP_REASONS.APP_SHUTDOWN);
  File "resource://gre/modules/XPIProvider.jsm", line 3742, in XPI_callBootstrapMethod
    this.bootstrapScopes[aId][aMethod](params, aReason);
  File "jar:file:///home/ove/.mozilla/firefox/3yqpwadl.default/extensions/[e-mail]!/bootstrap.js", line 229, in shutdown
    unload(loader, reason);
  File "resource://jid1-izhfvv5cr1cgdg-at-jetpack/addon-sdk/lib/toolkit/loader.js", line 368, in unload
    notifyObservers(subject, 'sdk:loader:destroy', reason);
  File "resource://jid1-izhfvv5cr1cgdg-at-jetpack/addon-sdk/lib/sdk/system/events.js", line 62, in 
    data: data
  File "resource://jid1-izhfvv5cr1cgdg-at-jetpack/addon-sdk/lib/sdk/system/unload.js", line 77, in onunload
    unload(reason);
  File "resource://jid1-izhfvv5cr1cgdg-at-jetpack/addon-sdk/lib/sdk/system/unload.js", line 56, in unload
    observers.forEach(function(observer) {
  File "resource://jid1-izhfvv5cr1cgdg-at-jetpack/addon-sdk/lib/sdk/system/unload.js", line 58, in 
    observer(reason);
  File "resource://jid1-izhfvv5cr1cgdg-at-jetpack/addon-sdk/lib/sdk/system/unload.js", line 67, in 
    unloaders.slice().forEach(function(unloadWrapper) {
  File "resource://jid1-izhfvv5cr1cgdg-at-jetpack/addon-sdk/lib/sdk/system/unload.js", line 68, in 
    unloadWrapper(reason);
  File "resource://jid1-izhfvv5cr1cgdg-at-jetpack/addon-sdk/lib/sdk/system/unload.js", line 41, in unloadWrapper
    originalDestructor.call(obj, reason);
  File "resource://jid1-izhfvv5cr1cgdg-at-jetpack/addon-sdk/lib/sdk/widget.js", line 346, in destroy
    this._views[i].destroy();
  File "resource://jid1-izhfvv5cr1cgdg-at-jetpack/addon-sdk/lib/sdk/widget.js", line 470, in WidgetView_destroy
    this._chrome.destroy();
  File "resource://jid1-izhfvv5cr1cgdg-at-jetpack/addon-sdk/lib/sdk/widget.js", line 927, in WC_destroy
    this.node.parentNode.removeChild(this.node);

====================

Also, the widget did not save its state and reappeared in the add-on bar after the browser was restarted.


Expected results:

No exceptions; the widget does not add itself to the add-on bar when the browser is started again.

Comment 1

[Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)]

Alex, can you take a look at this?

Comment 2

[Alexandre Poirot [:ochameau]]

We are having yet another issue with the customization dialog, where some exception happens when we are trying to initialize widget iframe while the widget is detached from DOM in the toolbar palette...

I'm on it. I already have a workaround patch, but I'd prefer to land a sane fix with some firefox tweaks.

Comment 3

[Alexandre Poirot [:ochameau]]

Attachment: Pull request 917

Here is a patch that uses bug 854962 new event to better handle user customization of widgets (when an item is moved across toolbar and moved to the palette)

I need to do some more testing against bug 854962 patch before asking review,
but feedback is much appreciated at any time.

Comment 4

[u463949]

Thank you for helping. This fixes the original problem, but when you access the widget (e.g. changing the icon) while it is in the palette, there is fallout:

TypeError: this._symbiont is null
resource://jid0-9xfbwuwnvpx4wwsfbwmcm4jj69e-at-jetpack/addon-sdk/lib/sdk/widget.js 703
Traceback (most recent call last):
  File "resource://jid0-9xfbwuwnvpx4wwsfbwmcm4jj69e-at-jetpack/addon-sdk/lib/sdk/timers.js", line 31, in notify
    callback.apply(null, args);
  File "resource://jid0-9xfbwuwnvpx4wwsfbwmcm4jj69e-at-jetpack/self-destructing-cookies/lib/main.js", line 108, in exports.realmain
    introduction: newInstall
  File "resource://jid0-9xfbwuwnvpx4wwsfbwmcm4jj69e-at-jetpack/self-destructing-cookies/lib/gui-desktop.js", line 86, in exports.setup
    for (var t in tabs) exports.handleTabChanged(tabs[t]);
  File "resource://jid0-9xfbwuwnvpx4wwsfbwmcm4jj69e-at-jetpack/self-destructing-cookies/lib/gui-desktop.js", line 162, in exports.handleTabChanged
    view.port.emit("icon", self.data.url("toolbar-r.png"));
  File "resource://jid0-9xfbwuwnvpx4wwsfbwmcm4jj69e-at-jetpack/addon-sdk/lib/sdk/widget.js", line 394, in 
    self._chrome.update(self._baseWidget, "emit", arguments);
  File "resource://jid0-9xfbwuwnvpx4wwsfbwmcm4jj69e-at-jetpack/addon-sdk/lib/sdk/widget.js", line 703, in WC_update
    let port = this._symbiont.port;

The widget is invisible after this until you restart the browser.

Comment 5

[Alexandre Poirot [:ochameau]]

(In reply to Ove Soerensen from comment #4)
> Thank you for helping. This fixes the original problem, but when you access
> the widget (e.g. changing the icon) while it is in the palette, there is
> fallout:
> ...
> The widget is invisible after this until you restart the browser.

Thanks for testing the patch so quickly!
I just pushed a new commit that should prevent this meaningless exception. 
But we may warn and throw a meaningfull error here, when you try to communicate with a widget that is hidden.
Otherwise, this new commit will most likely not solve the invisible widget. I would imagine the main issue is that this SDK patch depends on bug 854962, that is in Firefox codebase and still not landed, so still not available in nightly.

Comment 6

[u463949]

From a purely egoistical point of view, I would find it most convenient if the widget would just ignore me while it is hidden :). Is it even possible for an add-on to determine if a widget is visible? There does not seem to be an obvious way, at least judging from the documentation. Anyway, great to see progress on this; kudos.

Comment 7

[Alexandre Poirot [:ochameau]]

Looks like I won't have time to look at SDK bugs anymore.

Comment 8

[Erik Vold [:erikvold] (please needinfo? me)]

Let's take a look at this again in triage.

Comment 9

[Jeff Griffiths (:canuckistani) (:⚡︎)]

widget is being removed.