Since we've split (local, remotes) branches to (locals, remotes { branches }),
.has_branch() API no longer makes much sense. Callers often need to check if
a remote branch is tracked.
Otherwise, newly created default branch would be re-imported as a new Git HEAD.
This could be addressed by cmd_git_init(), but the same situation can be
crafted by using "git checkout -b".
This should be a no-op, though that is not necessarily obvious in corner
cases.
Note that libgit2 already performs the push negotiation even when
pushing without force (without `+` in the refspec).
As explained in the commit, our logic is a bit more complicated than
that of `git push --force-with-lease`. This is to match the behavior of
`jj git fetch` and branch conflict resolution rules.
In chromium/src.git, this gives an approximate ~0.83s speedup for
commands if the Git index is empty, and a ~0.14s slowdown if the Git
index is non-empty.
As most users using jj will likely be using jj to write to a colocated
repo - and therefore avoid modifying the Git index - this should be a
general speedup for most colocated checkouts.
This implements the other workaround described in 57167cefda "git: on
import_refs(), don't abandon ancestors of newly fetched refs":
> I think there are two ways to fix the problem:
> a. pin non-tracking remote branches just like local refs
> b. pin newly fetched refs in addition to local refs
> This patch implements (b) because it's simpler and more obvious that the
> fetched commits would never be abandoned immediately.
The idea of (a) is that untracked remote branches are independent read-only
refs, and read-only branches shouldn't be rewritten implicitly. Once the
branch gets rewritten or abandoned by user, these remote refs will be hidden,
and won't be pinned anymore.
Since (a) effectively supersedes (b), this patch also removes the original
workaround.
Fixes#3495
Apparently, gix has 100ms timeout. Since this test tries to create contended
situation, it's possible that the ref lock can't be acquired. I've added
upper bound to the retry loop at b37293fa68 "tests: add upper bound to
test_concurrent_read_write_commit() loop", so ignoring arbitrary errors
should be okay.
The problem can be reproduced on my Linux machine by inserting 10ms sleep() to
gix and increasing the concurrency.
Fixes#3069
I'm going to make WorkspaceCommandHelper::maybe_snapshot() snapshot the working
copy before importing refs. git::import_some_refs() can rebase the working copy
branch and therefore @ can be moved. git::import_head() doesn't, and it should
be invoked before snapshotting.
git::import_head() is inserted to some of the git:import_refs() callers where
HEAD seems to matter. I feel it's a bit odd that the HEAD ref is imported to
non-colocated repo, but "jj init --git-repo" relies on that, and I think the
existence of HEAD@git is harmless. It's merely a ref to the revision checked
out somewhere else.
I'm going to add a prefix resolution method to OpStore, but OpStore is
unrelated to the index. I think ObjectId, HexPrefix, and PrefixResolution can
be extracted to this module.
It seems better to have the caller pass the transaction description
when we finish the transaction than when we start it. That way we have
all the information we want to include more readily available.
Gitoxide errors don't implement PartialEq. We could instead stringify the
errors, but there aren't many callers who expect FailedRefExportReason to
be comparable.
Hopefully this will fix the unfinished Windows CI issue. A possible scenario
is that recent migration to gitoxide made this test flaky on Windows. For
example, gitoxide might have in-memory object cache that relies on file mtime,
and occasionally fails to detect new object on Windows.
If a commit pointed to by HEAD or ref is missing, the ref is considered
invalid and excluded by import_refs(). The current test behavior appears to
depend on some in-memory cache of git2::Repository.
GitBackend will use it to configure gix::Repository. I think UserSettings
is generally useful to pass store-specific parameters, so I've updated all
factory functions.
This means that the commits previously pinned by remote branches are no longer
abandoned. I think that's more correct since "push" is the operation to
propagate local view to remote, and uninteresting commits should have been
locally abandoned.
Since pushed remote branches will share the common base targets with locals,
these branches should be marked as tracking. git::push_branches() will handle
that. It looks ugly that the public GitBranchPushTargets type keeps "force"-d
branches as a separate set, but we'll need to rework that anyway when we
implement --force-with-lease behavior. So let's leave it for now.
Some of the git::push_updates() tests have been migrated to the new function.
I left a couple of basic tests for git::push_updates() because push_updates()
will be used to implement a low-level "jj git push-refs" command.
I made import_refs() not preserve commits referenced by remote branches at
520f692a46 "git: on import_refs(), don't preserve old branches referenced by
remote refs." The idea is that remote branches are weak, and commits referenced
by these refs can be freely rewritten by future local changes without moving
the refs. I don't think that's wrong, but 520f692a46 also made "new" remote
changes be abandoned by old remote refs. This problem occurs only when
git.auto-local-branch is off.
I think there are two ways to fix the problem:
a. pin non-tracking remote branches just like local refs
b. pin newly fetched refs in addition to local refs
This patch implements (b) because it's simpler and more obvious that the
fetched commits would never be abandoned immediately.
`ReadonlyRepo::init()` takes callbacks for initializing each kind of
backend. We called these things like `op_store_initializer`. I found
that confusing because it is not a `OpStoreFactory` (which is for
loading an existing backend). This patch tries to clarify that by
renaming the arguments and adding types for each kind of callback
function.
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.
I've added a boolean flag to the store to ensure that the migration never runs
more than once after the view gets "op restore"-d. I'll probably reorganize the
branches structure to support non-tracking branches later, but updating the
storage format in a single commit would be too involved.
If jj is downgraded, these "git" remote refs would be exported to the Git repo.
Users might have to remove them manually.
As we can set HEAD to an arbitrary ref by using .reference_symbolic(), we don't
have to manage a ref that can also be valid as a branch name.
Fixes#1495
It makes the call sites clearer if we pass the `TestRepoBackend` enum
instead of the boolean `use_git` value. It's also more extensible (I
plan to add another backend for tests).
