revlog: always use a Rust index for REVLOGv1 if rustext is present
We are about to change classes such as `rustext.AncestorsIterator` to
take a Rust index, hence we cannot have the option not to use the Rust
index.
Note: this can be refined depending on whether we want to keep this
option or not. We will have to make two versions of `AncestorsIterator`
and its sibling to support REVLOGV2 and CHANGELOGv2 anyway.
Meanwhile, this is the simplest change to make the tests pass.
Mercurial
=========
Mercurial is a fast, easy to use, distributed revision control tool
for software developers.
Basic install::
$ make # see install targets
$ make install # do a system-wide install
$ hg debuginstall # sanity-check setup
$ hg # see help
Running without installing::
$ make local # build for inplace usage
$ ./hg --version # should show the latest version
See https://mercurial-scm.org/ for detailed installation
instructions, platform-specific notes, and Mercurial user information.
Notes for packagers
===================
Mercurial ships a copy of the python-zstandard sources. This is used to
provide support for zstd compression and decompression functionality. The
module is not intended to be replaced by the plain python-zstandard nor
is it intended to use a system zstd library. Patches can result in hard
to diagnose errors and are explicitly discouraged as unsupported
configuration.