We had similar code in two places for restoring paths from one tree to
another. Let's reuse it instead.
I put the new function in the `rewrite` module. I'm not sure if that's
right place. Maybe it belongs in `tree`?
Since gix::Repository::config_snapshot() borrows the repo instance, it has to
be allocated in caller's stack. That's why GitBackend::git_config() is removed.
My gut feeling is that gitoxide aims to be more transparent than libgit2. We'll
need to know more about the underlying Git data model.
Random comments on gix API:
* gix::Repository provides API similar to git2::Repository, but has less
"convenient" functions. For example, we need to use .find_object() +
.try_to/into_<kind>() instead of .find_<kind>().
* gix::Object, Blob, etc. own raw data as bytes. gix::object and gix::objs
types provide high-level views on such data.
* Tree building is pretty low-level compared to git2.
* gix leverages bstr (i.e. bytes) extensively.
It's probably not difficult to migrate git::import/export_refs(). It might
help eliminate the startup overhead of libssl initialization. The gix-based
GitBackend appears to be a bit faster, but that wouldn't practically matter.
#2316
If we create a `ColorFormatter`, add some labels to it, print
something using the configured style, and then return early because of
an error, we would leave the terminal in a bad state. I think many
shells reset color codes after a command returns, but let's still do
our best.
Like "jj log PATHS...", unmatched name isn't an error. I don't think
"jj branch list glob:'push-*'" should fail just because there are no in-flight
PR branches.
This avoids https://github.com/rust-lang/futures-rs/issues/2090. I
don't think we need to worry about reading legacy conflicts
asynchronously - async is really only useful for Google's backend
right now, and we don't use the legacy format at Google. In
particular, I don't want `MergedTree::value()` to have to be async.
