1661162 - delayed_window_print.html causes leakcheck failures because the harness doesn't wait for the print process to finish.

Status: NEW

(Core :: Printing: Setup, defect, P3)

Comment 1

[Daniel Holbert [:dholbert]]

Related note: the .ini file for delayed_window_print.html also has this pref-setting line with an explanatory comment:

  comment: Our own save-to-pdf "printer" knows how to respect print.always_print_silent
  prefs: [print.always_print_silent:true, "print_printer:Mozilla Save to PDF"]

https://searchfox.org/mozilla-central/rev/c036a209f5a2c3163d1277ee2b7becaab2f79dbd/testing/web-platform/mozilla/meta/dom/delayed_window_print.html.ini#4

It turns out the comment is not quite right. If I run this WPT test locally, I do get a silent print, but it goes to my actual physical system-default printer -- not to the Mozilla Save to PDF print-target.

I filed bug 1879474 on this.

Comment 2

[Daniel Holbert [:dholbert]]

I'm seeing what I think is the same issue when writing a WPT-based (& in a previous attempt at a mochitest-based) crashtest for bug 1833279.

One thing I'm noticing is that the leaks seem to only be reported on Windows and macOS. Linux and Android seem to be fine, for whatever reason (so far at least).

Here's the Try run where I'm observing that, for my test:
https://treeherder.mozilla.org/jobs?repo=try&resultStatus=testfailed%2Cbusted%2Cexception%2Csuccess%2Crunning%2Cpending%2Crunnable&revision=f8218eea77663af5f1b5710a3ac2832b4f358d43