1127944 - Legacy vcs sync assumes hg repository "tip" is the new Git branch head

Status: RESOLVED FIXED

(Release Engineering :: General, defect)

Description

[Gregory Szorc [:gps]]

The work in bug 927219 broke legacy vcs sync because legacy vcs sync assumes the hg repo "tip" commit corresponds to the Git branch that should be pushed. The code is here: https://hg.mozilla.org/users/hwine_mozilla.com/repo-sync-tools/file/d957174f1baf/keep_updated#l46

If the tip-most commit belongs to a different head, legacy vcs sync will attempt a non-fast-forward.

The errors currently occurring in legacy vcs sync (see also bug 1127172) are because it is attempting to force push a branch closure commit for a different head to the e.g. v1.4 Git branch.

Changing legacy vcs sync to run `hg id -r default` instead of `hg id` (which takes the "tip" commit by default) should be all that is needed to fix this. The assumption here is that every repository we sync has changes coming from the "default" Mercurial branch.

Comment 1

[Hal Wine [:hwine] use NI!]

This same issue was detected on the code for most conversion in bug 854437. "Combo" (gecko.git) code was not changed at that time, most likely out of concern of touching seeming working code.

Comment 2

[Hal Wine [:hwine] use NI!]

Attachment: use-default.patch

running in production with:
  http://hg.mozilla.org/users/hwine_mozilla.com/repo-sync-tools/rev/b61ed6d1cfa0

Comment 3

[Hal Wine [:hwine] use NI!]

done with comment 2, closing