rhg: Add support for `rhg status --copies`
Copy sources are collected during `status()` rather than after the fact like
in Python, because `status()` takes a `&mut` exclusive reference to the dirstate map
(in order to potentially mutate it for directory mtimes) and returns `Cow<'_, HgPath>`
that borrow the dirstate map.
Even though with `Cow` only some shared borrows remain, the still extend the same
lifetime of the initial `&mut` so the dirstate map cannot be borrowed again
to access copy sources after the fact:
https://doc.rust-lang.org/nomicon/lifetime-mismatch.html#limits-of-lifetimes
Additionally, collecting copy sources during the dirstate tree traversal that
`status()` already does avoids the cost of another traversal or other lookups
(though I haven’t benchmarked that cost).
Differential Revision: https://phab.mercurial-scm.org/D11899
test sparse
$ cat >> $HGRCPATH << EOF
> [ui]
> username = nobody <no.reply@fb.com>
> [extensions]
> sparse=
> purge=
> strip=
> rebase=
> EOF
$ hg init myrepo
$ cd myrepo
$ echo a > index.html
$ echo x > data.py
$ echo z > readme.txt
$ cat > webpage.sparse <<EOF
> [include]
> *.html
> EOF
$ cat > backend.sparse <<EOF
> [include]
> *.py
> EOF
$ hg ci -Aqm 'initial'
$ cd ..
Verify local clone with a sparse profile works
$ hg clone --enable-profile webpage.sparse myrepo clone1
updating to branch default
warning: sparse profile 'webpage.sparse' not found in rev 000000000000 - ignoring it
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd clone1
$ ls -A
.hg
index.html
$ cd ..
Verify local clone with include works
$ hg clone --include *.sparse myrepo clone2
updating to branch default
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd clone2
$ ls -A
.hg
backend.sparse
webpage.sparse
$ cd ..
Verify local clone with exclude works
$ hg clone --exclude data.py myrepo clone3
updating to branch default
4 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd clone3
$ ls -A
.hg
backend.sparse
index.html
readme.txt
webpage.sparse
$ cd ..
Verify sparse clone profile over ssh works
$ hg clone -q --enable-profile webpage.sparse ssh://user@dummy/myrepo clone4
warning: sparse profile 'webpage.sparse' not found in rev 000000000000 - ignoring it
$ cd clone4
$ ls -A
.hg
index.html
$ cd ..