May be unlocked files pulled from elsewhere, but converting from direct
mode will add more. So, do the scan for them first, since it empties
anything currently in the database.
WorkTree.lookupFile was finding a key for a file that's deleted from the
work tree, which is different than the v5 behavior (though perhaps the same
as the direct mode behavior). Fix by checking that the work tree file exists
before catting its key.
Hopefully this won't slow down much, probably the catKey is much more expensive.
I can't see any way to optimise this, except perhaps to make Command.Unused
check if work tree files exist before/after calling lookupFile. But,
it seems better to make lookupFile really only find keys for worktree files;
that's what it's intended to do.
Else, queued file stages won't have reached the index, and it won't find
everthing.
This evidently fixes a reversion in my work today, although I don't see how
I broke it. It didn't use to flush the queue first, before, and worked
somehow.
Test suite for v5 is back to 100% green now.
The smudge filter does need to be run, because if the key is in the local
annex already (due to renaming, or a copy of a file added, or a new file
added and its content has already arrived), git merge smudges the file and
this should provide its content.
This does probably mean that in merge conflict resolution, git smudges the
existing file, re-copying all its content to it, and then the file is
deleted. So, not efficient.
This is a behavior change for merge conflicts between locked files
that both pointed to the same key, in different ways.
Before, the conflict was resolved, but the file was renamed to .variant.
This was unnecessary, because there was only one variant.
Of course, this also handles conflicts between unlocked and locked, or even
two unlocked files with different pointer contents.
Since the file was present and locked, its annex object was not in the
inode cache. So, despite not needing to update the annex object when the
clean filter is run on the content by git merge, it does need to record the
inode cache of the annex object. Otherwise, the annex object will be
assumed to be bad, since its inode is not cached.
Several tricky parts:
* When the conflict is just between the same key being locked and unlocked,
the unlocked version wins, and the file is not renamed in this case.
* Need to update associated file map when conflict resolution renames
an unlocked file.
* git merge runs the smudge filter on the conflicting file, and actually
overwrites the file with the same content it had before, and so
invalidates its inode cache. This makes it difficult to know when it's
safe to remove such files as conflict cruft, without going so far as to
compare their entire contents.
Dealt with this by preventing the smudge filter from populating the file
when a merge is run. However, that also prevents the smudge filter being
run for non-conflicting files, so eg moving a file won't put its new
content into place.
* Ideally, if a merge or a merge conflict resolution renames an unlocked
file, the file in the work tree can just be moved, rather than copying
the content to a new worktree file.
This is attempted to be done in merge conflict resolution, but
due to git merge's behavior of running smudge filters, what actually
seems to happen is the old worktree file with the content is deleted and
rewritten as a pointer file, so doesn't get reused.
So, this is probably not as efficient as it optimally could be.
If that becomes a problem, could look into running the merge in a separate
worktree and updating the real worktree more efficiently, similarly to the
direct mode merge. However, the direct mode merge had a lot of bugs, and
I'd rather not use that more error-prone method unless really needed.
