Mostly, I was a bit confused that some of these functions return a
`TrackingRefPair` but don't seem to take into account whether the remote
branch is being tracked or not.
We've had the public_heads for as long as we've had the View object,
IIRC (I didn't check), but we still don't use it for anything. I don't
have any concrete plans for using it either. Maybe our config for
immutable commits is good enough, or maybe we'll want something more
generic (like Mercurial's phases). For now, I think we should simplify
by removing it the storage for public heads.
Since hidden commits can be looked up by remote_branches() revset for example,
reindexing should traverse ancestors from all named refs in addition to the
visible heads.
Since "jj git fetch --branch" supports glob patterns, users would expect that
"jj git push --branch glob:.." also works.
The error handling bits are copied from "branch" sub commands. We might want to
extract it to a common helper function, but I haven't figured out a reasonable
boundary point yet.
Since local/remote branches are now of different types, it doesn't make much
sense to dispatch merging through RefName. Let's add merge_<kind>() methods
instead.
MutableRepo handles merging of the other kind of refs internally, and the
merge function is short enough to inline. I also removed early returns since
most callers provide non-identical ref targets, and merge_ref_targets() should
be cheap if the inputs can be trivially merged.
This partially reverts the change in 30fb7995c2 "view: make local/remote
branches iterator yield RemoteRef instead of RefTarget." As I'm going to add
diff function for RemoteRef pairs, we'll need a generic version of merge-join
iterator anyway.
We'll use remote_ref.tracking_target() to classify push action, but not all
callers of local_remote_branches() need tracking_target() instead of target.
The state field isn't saved yet. git import/export code paths are migrated,
but new tracking state is always calculated based on git.auto-local-branch
setting. So the tracking state is effectively a global flag.
As we don't know whether the existing remote branches have been merged in to
local branches, we assume that remote branches are "tracking" so long as the
local counterparts exist. This means existing locally-deleted branch won't
be pushed without re-tracking it. I think it's rare to leave locally-deleted
branches for long. For "git.auto-local-branch = false" setup, users might have
to untrack branches if they've manually "merged" remote branches and want to
continue that workflow. I considered using git.auto-local-branch setting in the
migration path, but I don't think that would give a better result. The setting
may be toggled after the branches got merged, and I'm planning to change it
default off for better Git interop.
Implementation-wise, the state enum can be a simple bool. It's enum just
because I originally considered to pack "forgotten" concept into it. I have
no idea which will be better for future extension.
Since set_remote_branch_target() is called while merging refs, its tracking
state shouldn't be reinitialized. The other callers are migrated to new setter
to keep the story simple.
This isn't important, but I'm going to change remote_targets to store RemoteRef
instead of RefTarget, so I went ahead and change the other field types as well.
There's a subtle behavior change. Unlike the original remove_remote_branch(),
remote_views entry is not discarded when the branches map becomes empty. The
reasoning here is that the remote view can be added/removed when the remote
is added/removed respectively, though that's not implemented yet. Since the
serialized data cannot represent an empty remote, such view may generate
non-unique content hash.
get_branch() would need to reconstruct the remote_targets map if we migrate
the underlying data structure to per-remote views. Let's remove the method as
it is only used in tests.
Alternatively, we can wrap BTreeMap<String, Option<RefTarget>> to flatten
Option<&Option<..>> internally, but doing that would be tedious. It would
also be unclear if map.remove(name) should construct an absent RefTarget if
the ref doesn't exist.
Perhaps, all view.get_<kind>(name) functions can return reference, but I'm
not willing to change the interface at this point. I'll revisit this after
migrating Option<RefTarget> to new Conflict-based type.
If we migrate RefTarget to new Conflict-based type, it won't store
Conflict<CommitId>, but Conflict<Option<CommitId>>. As the Option will
be internalized, new RefTarget type will also represent an absent target.
The 'target: Option<RefTarget>' argument will be replaced with new RefTarget
type.
I've also renamed the function for consistency with the following changes.
It would be surprising if set_local_branch(name, target) could remove the
branch. I feel the name set_local_branch_target() is less confusing.
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>`.
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.
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.
`wc_commit` seems clearer than `checkout` and not too much longer. I
considered `working_copy` but it was less clear (could be the path to
the working copy, or an instance of `WorkingCopy`). I also considered
`working_copy_commit`, but that seems a bit too long.
