manifestcache: add some test involving shares Some issue around shares have been reported. I am adding tests to better cover the share case. The test show that the code behave as expected so far. Differential Revision: https://phab.mercurial-scm.org/D7602

fuzz: fix test-fuzz-targets.t to run with python3 Differential Revision: https://phab.mercurial-scm.org/D7601

py3: fix a bytes vs str issue in remotefilelog extension Differential Revision: https://phab.mercurial-scm.org/D7598

rust-matchers: add doctests for `AlwaysMatcher` Differential Revision: https://phab.mercurial-scm.org/D7527

rust-hg-path: add method to get part of a path relative to a prefix This will be used in the next patch in this series. Differential Revision: https://phab.mercurial-scm.org/D7526

rust-matchers: improve `Matcher` trait ergonomics `VisitChildrenSet` has no need to own the set, this will save allocations. The `file_set` return type change is motivated by both ergonomics and... being able to compile code. The `AlwaysMatcher` does not store a `file_set`, which requires it to return an owned `HashSet`, which in turn would change our return type to `Cow<&HgPath>` (lifetimes omitted). This is both un-ergonomic and troublesome for more complex lifetime issues (especially with the upcoming `FileMatcher` in the following patch). Differential Revision: https://phab.mercurial-scm.org/D7525

rust-dirs-multiset: use `AsRef` instead of concrete types when possible I also renamed `vec` to `dirstate`, because it was not a great name. Differential Revision: https://phab.mercurial-scm.org/D7524