view tests/lockdelay.py @ 45825:8f07f5a9c3de

worker: raise exception instead of calling sys.exit() with child's code

When a worker process returns an error code, we would call
`sys.exit()` with that exit code on the main process. The `SystemExit`
exception would then get caught in `scmutil.callcatch()`, which would
return that error code. The comment there says "Commands shouldn't
sys.exit directly", which I agree with. This patch changes it so we
raise a specific exception when a worker fails so we can catch
instead. I think that means that `SystemExit` is now always an
internal error.

(I had earlier thought that this call to `sys.exit()` was from within
the child process until Matt Harbison made me look again, so thanks
for that!)

Differential Revision: https://phab.mercurial-scm.org/D9287

# Dummy extension that adds a delay after acquiring a lock.
#
# This extension can be used to test race conditions between lock acquisition.

from __future__ import absolute_import

import os
import time


def reposetup(ui, repo):
    class delayedlockrepo(repo.__class__):
        def lock(self, wait=True):
            delay = float(os.environ.get('HGPRELOCKDELAY', '0.0'))
            if delay:
                time.sleep(delay)
            res = super(delayedlockrepo, self).lock(wait=wait)
            delay = float(os.environ.get('HGPOSTLOCKDELAY', '0.0'))
            if delay:
                time.sleep(delay)
            return res

    repo.__class__ = delayedlockrepo