Fix: win32print.SetJob sending ANSI to UNICODE API

[CristiFati]

Fix for #1281.

Confirmed when investigating [SO]: How to change username of job in print queue using python & win32print.

Modified the script in the bug. The scenario is even easier to reproduce: simply pass the dictionary returned by GetJob to SetJob, and the error pops up (actually there are different errors depending on level (1, 2) - as also encountered in the SO URL).

The cause is straightforward: JOB_INFO_* structures have LPTSTR (wchar_t* when built with -DUNICODE -D_UNICODE) members, while PyArg_ParseTupleAndKeywords, fills char* s for z format specifiers. Check [Python.Docs]: Parsing arguments and building values.

The fix is to specify the Unicode format specifier (Z).

After rebuilding the .pyd (and placing it in the site-packages dir), the error no longer pops up, and changing existing jobs string properties is possible (tried setting pUserName to random strings and the change is reflected in the print queue).

Environment: Python 3.9.9 (pc064) with PyWin32 303.

[mhammond]

That looks great, thanks! Do you mind adding an entry to CHANGES.txt with a mention of #1281 and crediting yourself however you like?

[CristiFati]

@mhammond: Done. Hmmm I wonder if it would be possible for CHANGES.txt (and most likely other files) to be excluded from CI workflows (partially possible with https://docs.github.com/en/actions/managing-workflow-runs/skipping-workflow-runs).

[mhammond]

Thank you!

I wonder if it would be possible for CHANGES.txt (and most likely other files) to be excluded from CI workflows (partially possible with https://docs.github.com/en/actions/managing-workflow-runs/skipping-workflow-runs).

Possibly, but it's quite rare that this happens, so my motivation is low - I'd welcome PRs etc though :)