rust: do a clippy pass
This is the result of running `cargo clippy` on hg-core/hg-cpython and fixing
the lints that do not require too much code churn (and would warrant a separate
commit/complete refactor) and only come from our code (a lot of warnings in
hg-cpython come from `rust-cpython`).
Most of those were good lints, two of them was the linter not being smart
enough (or compiler to get up to `clippy`'s level depending on how you see it).
Maybe in the future we could have `clippy` be part of the CI.
Differential Revision: https://phab.mercurial-scm.org/D8635
Checking how hg behaves when one side of a pull/push doesn't support
some capability (because it's running an older hg version, usually).
$ hg init repo1
$ cd repo1
$ echo a > a; hg add -q a; hg commit -q -m a
$ hg bookmark a
$ hg clone -q . ../repo2
$ cd ../repo2
$ touch $TESTTMP/disable-lookup.py
$ disable_cap() {
> rm -f $TESTTMP/disable-lookup.pyc # pyc caching is buggy
> cat <<EOF > $TESTTMP/disable-lookup.py
> from mercurial import extensions, wireprotov1server
> def wcapabilities(orig, *args, **kwargs):
> cap = orig(*args, **kwargs)
> cap.remove(b'$1')
> return cap
> extensions.wrapfunction(wireprotov1server, '_capabilities', wcapabilities)
> EOF
> }
$ cat >> ../repo1/.hg/hgrc <<EOF
> [extensions]
> disable-lookup = $TESTTMP/disable-lookup.py
> EOF
$ cat >> .hg/hgrc <<EOF
> [ui]
> ssh = "$PYTHON" "$TESTDIR/dummyssh"
> EOF
$ hg pull ssh://user@dummy/repo1 -r tip -B a
pulling from ssh://user@dummy/repo1
no changes found
$ disable_cap lookup
$ hg pull ssh://user@dummy/repo1 -r tip -B a
pulling from ssh://user@dummy/repo1
abort: other repository doesn't support revision lookup, so a rev cannot be specified.
[255]
$ disable_cap pushkey
$ hg pull ssh://user@dummy/repo1 -r tip -B a
pulling from ssh://user@dummy/repo1
abort: remote bookmark a not found!
[255]