chg: ignore already closed fds when cleaning up This should fix this error we see in the CI from time to time: ``` --- /tmp/mercurial-ci/tests/test-chg.t +++ /tmp/mercurial-ci/tests/test-chg.t.err @@ -187,6 +187,26 @@ $ chg bulkwrite --pager=on --color no --config ui.formatted=True paged! 'going to write massive data\n' killed! (?) + Traceback (most recent call last): + File "/tmp/hgtests._uvojvqb/install/lib/python/mercurial/commandserver.py", line 509, in _serverequest + sv.cleanup() + File "/tmp/hgtests._uvojvqb/install/lib/python/mercurial/chgserver.py", line 382, in cleanup + self._restoreio() + File "/tmp/hgtests._uvojvqb/install/lib/python/mercurial/chgserver.py", line 461, in _restoreio + os.close(fd) + OSError: [Errno 9] Bad file descriptor + Traceback (most recent call last): + File "/tmp/hgtests._uvojvqb/install/lib/python/mercurial/commandserver.py", line 693, in _acceptnewconnection + self._runworker(conn) + File "/tmp/hgtests._uvojvqb/install/lib/python/mercurial/commandserver.py", line 744, in _runworker + prereposetups=[self._reposetup], + File "/tmp/hgtests._uvojvqb/install/lib/python/mercurial/commandserver.py", line 509, in _serverequest + sv.cleanup() + File "/tmp/hgtests._uvojvqb/install/lib/python/mercurial/chgserver.py", line 382, in cleanup + self._restoreio() + File "/tmp/hgtests._uvojvqb/install/lib/python/mercurial/chgserver.py", line 461, in _restoreio + os.close(fd) + OSError: [Errno 9] Bad file descriptor [255] ```

tests: work around non-thread-safeness of sysconfig.get_config_var()

workflow: add a default template for Merge Request Introduce a first basic template to try the feature.

run-tests: prevent race-condition when picking a channel Before this, multiple jobs could search the list at the same time and pick the same free channel. We now project this search/assignment with a simple lock.

run-tests: send the test result after freeing the channel Sending the message about the test being "done" signals to the main thread that a new test can be started. Before this changeset, we sent this signal before freeing the channel, there is room for a race condition where a new test would search for a channel before the old test freed the one it used. This is an example of the failure it would produce: https://foss.heptapod.net/mercurial/mercurial-devel/-/jobs/552404

run-tests: also send a message in the Keyboard interrupt case The next patch will do something equivalent, so lets do the change in an independant changeset first in case we need to bisect something in the future.

rhg: correctly handle the case where diffs are encoded relative to nullrev returning a valid entry for nullrev fix chain that delta against nullrev.