An update would try to fetch any missing largefiles after having updated normal
files and standins. That could fail or be interrupted and would leave the
working directory in a state where the largefiles not only were missing but
also were scheduled for remove ... and where the old largefile was left in
place.
Instead we now remove old largefiles before starting to download and update
missing largefiles.
Override updaterepo() instead of individual methods that may not be called for
each subrepo. Add test.
Based on patch from Matt Harbison.
Changes the order of update-related messages (now largefiles comes before the
global status).
Don't lock/write on operations that should be readonly (status).
Always lock when writing the lfdirstate (rollback).
Don't write lfdirstate until after committing; state isn't actually changed
until the commit is complete.
Before, it was possible to create a
.hg/largefiles/hash
file with truncated content, i.e., content where
SHA-1(content) != hash
This breaks the fundamental invariant in largefiles that the file
content for files in .hg/largefiles hash to the filename.
