This allows evaluating ancestors/ranges involving filters significantly
faster. For instance, naively evaluating `::mine()` requires reading
every commit in the repo to check `mine()` on each commit, then finding
the ancestors of that set. This optimization rewrites `::mine()` to
`::heads(mine())`, since `heads(mine())` can be evaluated more
efficiently by only reading commits until the first successful match.
If someone is unaware of how revsets are implemented, this case can come
up pretty easily, such as by including `~mine()` in `immutable_heads()`
to make other people's commits immutable. In my local `jj` repo, this
optimization reduces the runtime of `jj log` with `~mine()` in
`immutable_heads()` from about 800ms down to about 50ms.
Benchmark results on Git repo:
```
::(v1.0.0..v2.40.0) 55.5% faster
author(peff).. 96.8% faster
```
There are no more callers of parse_function_argument_to_string(), so it's
removed. This function was a thin wrapper of literal parser, and can be
easily reintroduced if needed.
Suppose we have an alias 'immutable()' = '::immutable_heads()', user can
express (visible) mutable set as '~immutable()'. 'immutable_heads()..' can
terminate early, but a generic difference 'all() & ~immutable()' can't.
Suppose the generation value is usually small, it should be faster to do
bounded range look up first 'y-', then walk ancestors with the unwanted set
'y-..x'.
In my linux stable mirror, this makes the default log revset evaluation super
fast. immutable_heads(), if configured properly, includes many historical
branch heads which are also the visible heads.
revsets/immutable_heads()..
---------------------------
0 12.27 117.1±0.77m
3 1.00 9.5±0.08m
Summary: In preparation for unifying all workspace dependencies across all
crates, let's go ahead and move the jj-cli crate into its own new directory.
This will also be a nicer and more uniform layout as we add new `jj-*` crates.
Signed-off-by: Austin Seipp <aseipp@pobox.com>
Change-Id: Icf94e7ae5f290dc8e181215727b38ada
