Git's HEAD ref is similar to other refs and can logically have
conflicts just like the other refs in `git_refs`. As with the other
refs, it can happen if you run concurrent commands importing two
different updates from Git. So let's treat `git_head` the same as
`git_refs` by making it an `Option<RefTarget>`.
Add a new git.auto-local-branch config option. When set to false, a
remote-tracking branch imported from Git will not automatically create a
local branch target. This is implemented by a new GitSettings struct
that passes Git-related settings from UserSettings.
This behavior is particularly useful in a co-located jj and Git repo,
because a Git remote might have branches that are not of everyday
interest to the user, so it does not make sense to export them as local
branches in Git. E.g. https://github.com/gitster/git, the maintainer's
fork of Git, has 379 branches, most of which are topic branches kept
around for historical reasons, and Git developers wouldn't be expected
to have local branches for each remote-tracking branch.
I ran an upgraded Clippy on the codebase. All the changes seem to be
about using variables directly in format strings instead of passing
them as separate arguments.
To prevent git's GC from breaking a repo, we already add a git ref to
commits we create in the git backend. However, we don't add refs to
commits we import from git. This fixes that.
Closes#815.
There's no need to update our record of the ref if it didn't
change. This is just about making it clearer; I doubt it will have
measurable performance impact.
The function doesn't do much at all now and there's a single caller,
so let's inline it.
I tried to clean up the code a bit futher so it wouldn't even create
the `old_view`, but it was harder than I had hoped. I might get back
to it later.
@yuja asked on #701 about the difference between the state in the
`git_export_view` and what we have in `mut_repo.view()`. It's true
that the branches in `mut_repo.view().git_refs()` should match what we
wrote to disk. We can therefore remove the on-disk storage and
simplify quite a bit. For now, I create the `last_export_view` from
the `mut_repo.view().git_refs()` before calling
`export_changes()`. I'll clean up a bit more next.
I think this is correct even considering e.g. undo. Let's consider
what would happen in a non-colocated Git repo (not because tricky
cases cannot happen there but because the explicit exports and imports
make it easier to discuss, and more cases can occur). If the user
moved a branch and then did `jj git export`, `jj undo`, and then `jj
git export` again, we would think on the second export that we should
perform the same changes to the Git repo, which should have no effect.
This patch also fixes the bug we were forced to work around in the
test case in the previous patch.
This removes one of our uses of Thrift.
This fixes the bugs shown by the tests added in the previous patch by
checking that the git branches we're about to update have not been
updated by git since our last export. If they have, we fail those
branches. The user can then re-import from the git repo and resolve
any conflicts before exporting again.
I had to update the `test_export_import_sequence` to make it
pass. That shows a new bug, which I'll fix next. The problem is that
the exported view doesn't get updated on import, so we would try to
export changes compared to an earlier export, even though we actually
knew (because of the `jj git import`) that the state in git had
changed.
Let's acknowledge everyone's contributions by replacing "Google LLC"
in the copyright header by "The Jujutsu Authors". If I understand
correctly, it won't have any legal effect, but maybe it still helps
reduce concerns from contributors (though I haven't heard any
concerns).
Google employees can read about Google's policy at
go/releasing/contributions#copyright.
84b924946f switched to requiring both
SSH_AUTH_SOCK and SSH_AGENT_PID for an agent to be used. This doesn't
seem to be a typical situation, so perhaps it was not intended.
To reduce conflicts between branches like `main` and `main/sub`, it's
better to first delete refs in git that have been deleted in jj, and
then add/update refs that have been added/updated in jj.
Since we now write a (partial) view object of the exported branches to
disk (since 7904474320), we can safely skip exporting some
branches. We already skip conflicted branches. This commit makes us
also skip branches that we fail to write to the backing Git repo,
instead of failing the whole operation (after possibly updating some
Git refs).
I made the `export_refs()` function return the branches that
failed. We should probably make that a struct later and have a
separate field for branches that we skipped due to conflicts.
Closes#493.
When skipping branches we fail to update in the backing Git repo, we
must also skip updating the `exported_view` object, so we don't trick
ourselves into thinking the branch was already updated in the Git repo
on the next export.
I'm going to make the export skip branches that we fail to update in
the Git repo. For that, we need to know the branch name while
interacting with the `git2::Repository` object. This little
refactoring prepares for that.
The comment says that we collect the changes to make before making
them, in order to reduce the risk of making some changes before
failing. However, there is nothing in the code that collects changes
that can fail, and it's all doing comparisons in memory, so it should
be very fast. It's been like that since I added it in 47b3abd0f7. We
still need to preserve the structure to avoid mutating `mut_repo`
while iterating over branches, however, so I just updated the comment.
When we export branches to Git, we didn't update our own record of
Git's refs. This frequently led to spurious conflicts in these refs
(e.g. #463). This is typically what happened:
1. Import a branch pointing to commit A from Git
2. Modify the branch in jj to point to commit B
3. Export the branch to Git
4. Update the branch in Git to point to commit C
5. Import refs from Git
In step 3, we forgot to update our record of the branch in the repo
view's `git_refs` field. That led to the import in step 5 to think
that the branch moved from A to C in Git, which conflicts with the
internal branch target of B.
This commit fixes the bug by updating the refs in the `MutableRepo`.
Closes#463.
As I said in the previous patch, I don't know why I made the initial
export to Git a no-op. Exporting everything makes more sense to
(current-)me. It will make it slightly easier to skip exporting
conflicted branches (#463). It also lets us remove a `jj export` call
from `test_templater.rs`.
The first time we export to Git, we don't actually export
anything. That's a little weird and I don't know why I did it that
way. It seems more natural to export the current state. I'd like to
change it to do that. However, that currently means we'll detach the
current HEAD if it points to any of the branches we export. This patch
restructures the code a bit and skips the detach step if the target
branch already points to the right commit.
We could write the view object to the operation store instead, but
then we would need to make sure we don't GC it (once we add support
for GC of the operation store).
I'm going to add other error variants for when we fail to read/write
to disk, and I don't think we need to have a custom message for each
in the CLI crate. It's easier to pass along the message from the lib
crate.
(`ConflictedBranch`, on the other hand, is an expected error so I
think we should continue to let let the CLI crate define the error
message for it.)
In order to fix#463, I'm going to make us export to Git a little
earlier, before finishing the transation. That means we won't have an
operation yet, but we don't need that anyway.
If you remove all refs from the backing Git repo and then run `jj git
import`, we would see that all commits disappeared from the Git repo,
so we would remove them from the jj repo too. However, we do that by
doing a history walk from old heads to the new heads, which includes
the root commit when the new heads is an empty set. That means that we
mark the root commit as abandoned, which led to a crash in
`rewrite.rs` (when we try pick the root commit's first parent to use
as parent for rebased commits).
I was trying to create a reproduction script for #412, but the script
ran into another bug first. The script removed all the local and
remote branches from the backing Git repo. I noticed that we would
then try to abandon all commits. We should still count Git HEAD's
target as visible and not try to abandon it. This patch fixes that.
When the remote rejects a push, we now say something like this:
```
Remote rejected the update of some refs (do you have permission to push to ["refs/heads/main"]?)
```
That message could be formatted better, but this seems good enough for
now. We should probably have some more custom conversion from
`GitPushError` to `CommandError` in the CLI layer.
I think I had not added tests for successful push before because I
thought there was some issue with testing it with libgit2. There *is*
an issue, which is that libgit2 requires the remote to be bare when
it's on local disk, but we can very easily make the git repo bare in
this test.
I also updated the error handling in the `git` module to not let
follow-on errors hide the real error and to not fail if two branches
moved to the same commit.
Now that I'm using GitHub PRs instead of pushing directly to the main
branch, it's quite annoying to have to abandon the old commits after
GitHub rebases them. This patch makes it so we compare the remote's
previous heads to the new heads and abandons any commits that were
removed on the remote. As usual, that means that descendants get
rebased onto the closest remaining commit.
This is half of #241. The other half is to detect rewritten branches
and rebase on top.
If you import Git refs, then rebase a commit pointed to by some Git
ref, and then re-import Git refs, you don't want the old commit to be
made a visible head again. That's particularly annoying when Git refs
are automatically updated by every command.
This patch adds a place for tracking the current `HEAD` commit in the
underlying Git repo. It updates `git::import_refs()` to record it. We
don't use it anywhere yet.
This is part of #44.
The recent e5dd93cbf7, whose description says "cleanup: make Vec
inside CommitId etc. non-public", made all ID types in the `backend`
module *except* for `CommitId` non-public :P This patch makes