Philip Withnall 0c1fa95827 tests: Fix race condition on cancellation in unix-streams test
The cancellable may be cancelled just after the operation succeeds in a
different thread. So instead of checking whether the cancellable is
cancelled, check whether the operation returned a `CANCELLED` error, and
*then* assert that the cancellable is cancelled.

This should fix
https://pwithnall.pages.gitlab.gnome.org/-/glib/-/jobs/2338552/artifacts/_build/meson-logs/testlog.txt:
```
ok 1 /unix-streams/basic
Bail out! GLib-GIO:ERROR:../gio/tests/unix-streams.c:149:main_thread_skipped: assertion failed (err == (g-io-error-quark, 19)): err is NULL
stderr:
```

Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
2022-10-17 13:02:02 +01:00
..
2021-05-13 22:16:27 +01:00
2020-11-17 15:50:07 +00:00
2019-01-10 13:50:26 -05:00