rust-cpython: introduce restricted variant of RefCell This should catch invalid borrow_mut() calls. Still the ref-sharing interface is unsafe.

tests: register test-merge-combination.t as small but slow run-tests.py use file size as an heuristic for test run time. The new `test-merge-combination.t` is a small file that do a lot of processing. As a result it tend to be scheduled really late but delay the full test run by a lot. On an example test run, the one-before-last test completed 279s after the start of the run, while `test-merge-combination.t` finished 355s after it. A 76s delay. This delay can be avoided since `test-merge-combination.t` only got started 175s after the start of the run.

test: allow different result for zstd compression (issue6188) test-repo-compengines fails on big-endian due to different file size, but the repo doesn't seem broken, so allow both sizes. Differential Revision: https://phab.mercurial-scm.org/D6787

rust-cpython: fix unsafe inner(py).borrow_mut() calls Since self.inner is managed by PySharedState, it must not be borrowed mutably through the RefCell interface. Otherwise, the underlying object could be mutated while a reference is leaked to Python world.

revlog: deprecate the use of `revision(..., raw=True)` We have an official `rawdata` function now.

Added signature for changeset a4e32fd539ab

Added tag 5.1.1 for changeset a4e32fd539ab

remotefilelog: reduce probability of race-condition in remotefilelog tests ca1014ad3de4 introduced a new parameter `ensurestart` to speed up remotefilelog background processes start. Unfortunately it seems to have increased the possibility of race-conditions in remotefilelog tests testing those background processes. With `ensurestart=False`, it seems that it's more probable to enter in a race condition with `debugwaitonprefetch` and `debugwaitonrepack` in remotefilelog background tests. Our CI seems to have a high probability of triggering this race condition so make it configurable to ensure tests are stable. Differential Revision: https://phab.mercurial-scm.org/D6772

rust: apply more formatting fixes My cargo fmt updated these lines and they look good.

rust-utils: add normalize_case util to mirror Python one While we still don't handle filenames properly cross-platform, this at least sticks closer to the Python behavior. Differential Revision: https://phab.mercurial-scm.org/D6756