update_canary.sh now also validates the exact package it is about to
publish as an upgrade from whatever stable names — 0.2.2 today, several
releases behind the laptop's canary. A package that upgrades the laptop
and breaks the desktops has to fail before it is published.
The lab print check runs in the Plasma lab as well as a plain container:
its rig lived in /tmp, which is a tmpfs there that docker cp cannot write
into, and its inline-PDF server shared a port with another test server.
docs/testing.md has the physical checks for 0.2.6.1 — paper through
Elmer, the real keyboard's zoom keys, the machine's graphics through
--diagnose, sign-out with a real account — before stable moves.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
The tab strip is drawn from the classroom's own palette, the one the
panel, Parent Call and Presentations read: larger titles, an accent
under the active tab, worksheets marked with a document icon. Its one
corner widget is the lesson's size and Print — not a new-tab button. With
one tab the strip stays hidden, as before; a change of size shows a
moment's badge instead, and the right-click menu and keys still work.
The window is named "Lesson — Wonder Ink" and carries its own icon.
The print preview showed "Page 1 could not be shown" in the real
session while printing correctly: poppler 25.03 does not write to stdout
when asked for "-" — it writes a file called "-.png" into the current
directory, which for Wonder Ink is the teacher's home. Pages are now
rendered into a directory of their own, and the lab print check fails
any preview that does not draw its page.
The teacher's manual has lesson size and printing.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Little Waders, 0.2.2: SIGSEGV in QPrinter::resolution() every time a
teacher confirmed a print job. QWebEngineView.print() keeps the raw
QPrinter pointer and returns; Qt's didPrintPage() reads
printer->resolution() once Chromium has rendered the page, and by then
PyQt had deleted the printer, which print_view() held only as a local.
Reproduced in the lab with the 0.2.2 code, same backtrace, no job.
Keeping the printer alive fixed the crash and was measured, and Qt's
path was still not a print path: a worksheet PDF tab printed as one
blank page, a lesson went as 24.6 MB of 300 dpi pictures with no text,
and a queue refusing jobs was reported as printed.
Print is now: make a PDF (a worksheet already is one; a lesson page is
printToPdf'd onto the printer's own paper; an inline PDF is downloaded
and opened as a worksheet), show it in a preview with printer, pages,
copies and colour, and hand it to CUPS with lp — Chrome's route in the
same rooms. Nothing asynchronous holds a printer. Black and white uses
the driver's ColorModel=Grayscale, because Elmer's generic PCL 6 driver
ignores print-color-mode.
An exception escaping any slot no longer aborts Wonder Ink: PyQt6's
default is to kill the process, and it is now logged instead.
tests/test-classroom-printing.sh: 50 checks. tools/lab/wonderink-print-
check: 39 checks over 13 scenarios in the lab, against a queue built
from Elmer's PPD, judged by what CUPS received. Not yet on paper.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
