crecord: remove obsolete version check An internal function shouldn't be checking compatibility with Mercurial versions.

histedit: remove "chistedit" mention from interface "chisted" is internal jargon. The end user should not need to be aware that it's different from histedit.

revset: improve documentation on expectsize() This is a follow-up patch to D5813. It improves the documentation of `expectsize(set, size)`. Differential Revision: https://phab.mercurial-scm.org/D5953

scmutil: fix a comment that doesn't match the code Differential Revision: https://phab.mercurial-scm.org/D5956

remotefilelog: remove strkwargs() The previous commit activated previously unused code paths on Python 3 and revealed that we were calling strkwargs() on a dict that already had str keys. The only caller of _forceprefetch() is _adjustlinknode() a few lines up and the static commonlogkwargs dict features str keys. Differential Revision: https://phab.mercurial-scm.org/D5958

remotefilelog: use raw strings when looking for variable names Keys in self.__dict__ and vars() are always str. So we need to use raw strings to ensure lookups work on Python 3. # skip-blame just r'' prefixes Differential Revision: https://phab.mercurial-scm.org/D5957

rust-cpython: binding for headrevs() This uses the core `dagops::retain_heads` to give a Rust implementation to `mercurial.dagop.headrevs`. Testing happens for now from `test-rust-ancestors.py` (for quick and minimal change), but it'd made more sense to put the binary index data elsewhere and to create a new test python module