view tests/crashgetbundler.py @ 33668:cde4cfeb6e3e stable

ui: restore behavior to ignore some I/O errors (issue5658)

e9646ff34d55 and 1bfb9a63b98e refactored ui methods to no longer
silently swallow some IOError instances. This is arguably the
correct thing to do. However, it had the unfortunate side-effect
of causing StdioError to bubble up to sensitive code like
transaction aborts, leading to an uncaught exceptions and failures
to e.g. roll back a transaction. This could occur when a remote
HTTP or SSH client connection dropped. The new behavior is
resulting in semi-frequent "abandonded transaction" errors on
multiple high-volume repositories at Mozilla.

This commit effectively reverts e9646ff34d55 and 1bfb9a63b98e to
restore the old behavior.

I agree with the principle that I/O errors shouldn't be ignored.
That makes this change... unfortunate. However, our hands are tied
for what to do on stable. I think the proper solution is for the
ui's behavior to be configurable (possibly via a context manager).
During critical sections like transaction rollback and abort, it
should be possible to suppress errors. But this feature would not
be appropriate on stable.

from __future__ import absolute_import

from mercurial.i18n import _
from mercurial import (
        changegroup,
        error,
        extensions
    )

def abort(orig, *args, **kwargs):
    raise error.Abort(_('this is an exercise'))

def uisetup(ui):
    extensions.wrapfunction(changegroup, 'getbundler', abort)