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
$ cat >> $HGRCPATH << EOF
> [extensions]
> strip=
> EOF
Setup repo
$ hg init repo
$ cd repo
Test backups list and recover
$ hg debugbackupbundle
no backup changesets found
$ mkcommit() {
> echo "$1" > "$1"
> hg add "$1"
> hg ci -l $1
> }
$ mkcommit a
$ mkcommit b
$ hg strip .
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
saved backup bundle to $TESTTMP/repo/.hg/strip-backup/d2ae7f538514-2953539b-backup.hg
$ hg debugbackupbundle
Recover changesets using: hg debugbackupbundle --recover <changeset hash>
Available backup changesets:
* (glob)
d2ae7f538514 b
$ hg debugbackupbundle --recover d2ae7f538514
Unbundling d2ae7f538514
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files
new changesets d2ae7f538514 (1 drafts)