Note that one test changed because the new `trivial_merge()` is more
strict than the old algorithm. I don't think that's a problem because
5-way conflicts are not very common, and I prefer to be strict now and
possibly relax it later if we decide that we would prefer that.
All call paths already check before calling the function that the
condition is true. One caller - `tree::try_resolve_file_conflict()` -
checks it itself. The other caller -
`conflicts::materialize_merge_result()` - doesn't, but its callers
have checked it via `extract_file_conflict_as_single_hunk()`.
The deleted comment about empty strings seems to be obsolete since
e48ace56d1. The caller pads the inputs with empty strings since that
commit.
I think we should ideally change this function's signature to make it
impossible to call it with bad inputs, and I hope to get back to that
soon.
We already resolve merge conflicts between hunks, trees, and refs, and
maybe more. They each have their own code for the handling trivial
merges (where the output is equal to one of the inputs). They look
surprisingly different. This commit adds a generic function for doing
that. Curiously, this new implementation uses implements it in yet
another way (basically using a multi-set).
I've added a helper function because the construction of the range expression
is a bit noisy. It could be a Repo method, but I don't want to make it a
default implementation of the trait method.
revset::walk_revs() let the caller handle RevsetEvaluationError since the
evaluation engine may error out even with such a trivial query. For now, most
callers just .unwrap() the error as before.
Otherwise, "jj init --git-repo ." would create extra table files per commit,
and merge them.
I considered adding an explicit GitBackend method to be called from
git::import_refs(), but the call order matters. The method should be invoked
before calling store.get_commit(..) or mut_repo.add_head(..). Since commits
are likely to be loaded from the head, we can instead make read_commit()
import ancestor metadata at all.
Alternatively, we could make a Git commit hidden until it's inserted into
the extra table. It's rather big change, and I wouldn't like to do that
without thinking more thoroughly.
I'm going to extract a helper function that converts git2::Commit to
backend::Commit struct, and the commit id can also be obtained from the
git2::Commit object.
My first attempt was to fix up corrupted index when merging, but it turned
out to be not easy because the self side may contain corrupted data. It's
also possible that two concurrent commit operations have exactly the same
view state (because change id isn't hashed into commit id), and only the
table heads diverge.
#924
GitBackend will reuse this lock to not assign multiple change ids to a
single commit. We could add a separate lock file that covers the section
from get_head() to save_table(), but I think reusing the table lock is good
enough.
This bug concerns the way `import_refs` that gets called by `fetch` computes
the heads that should be visible after the import.
Previously, the list of such heads was computed *before* local branches were
updated based on changes to the remote branches. So, commits that should have
been abandoned based on this update of the local branches weren't properly
abandoned.
Now, `import_refs` tracks the heads that need to be visible because of some ref
in a mapping keyed by the ref. If the ref moves or is deleted, the
corresponding heads are updated.
Fixes#864
Now that we return the written commit from `write_commit()`, let's
make the timestamps match what was actually written, accounting for
the whole-second precision and the adjustment we do to avoid
collisions.
The internal backend at Google doesn't let you write any value you
want for in the committer field. The `Store` type still caches the
value it attempted to write, which gets a little weird when the
written value is not what we tried to write. We should use the value
the backend actually wrote. However, we don't know if the backend
changed anything without reading the value back, which is often
wasteful. This commit changes the API to return the written value.
I only changed the signature of `write_commit()` for now. Maybe we
should make a similar change to `write_tree()`.
