revlog-native: introduced ABI version in capsule Concerns that an inconsistency could arise between the actual contents of the capsule in revlog.c and the Rust consumer have been raised after the switch to the array of data and function pointers in f384d68d8ea8. It has been suggested that the `version` from parsers.c could be use for this. In this change, we introduce instead a separate ABI version number, which should have the following advantages: - no need to change the consuming Rust code for changes that have nothing to do with the contents of the capsule - the version number in parsers.c is not explicitely flagged as ABI. It's not obvious to me whether an ABI change that would be invisible to Python would warrant an increment The drawback is that developers now have to consider two version numbers. We expect the added cost of the check to be negligible because it occurs at instantiation of `CIndex` only, which in turn is tied to instantiation of Python objects such as `LazyAncestors` and `MixedIndex`. Frequent calls to `Cindex::new` should also probably hit the CPU branch predictor. Differential Revision: https://phab.mercurial-scm.org/D7856

phases: make phasecache._phasesets immutable Previously, some code paths would mutate the cache itself, which could give weird results if multiple revsets got evaluated through that path. Differential Revision: https://phab.mercurial-scm.org/D7854

phases: reduce code duplication in phasecache.getrevset This is a functional NOP other than reducing some of the duplication in that method. Differential Revision: https://phab.mercurial-scm.org/D7853

scmutil: fix an unbound variable with progressbar debug enabled Differential Revision: https://phab.mercurial-scm.org/D7852

hgext: replace references to hashlib.sha1 with hashutil.sha1 When in a non-pure build of Mercurial, this will provide protections against SHA1 collision attacks. Differential Revision: https://phab.mercurial-scm.org/D7851

sslutil: migrate to hashutil.sha1 instead of hashlib.sha1 This is a straight-line replacement like the others, but I split it out since it's used in a network context and I'm not sure this is appropriate (we should probably drop support for sha1 fingerprints over TLS) and wanted this to be easily dropped. Differential Revision: https://phab.mercurial-scm.org/D7850

core: migrate uses of hashlib.sha1 to hashutil.sha1 Differential Revision: https://phab.mercurial-scm.org/D7849

hashutil: new package for hashing-related features Right now this just tries to use our sha1dc and if it's missing (eg a --pure build) we fall back to hashlib. I imagine in the future we'll want some other things in here for detecting what hasher is in use as we transition off sha1. Differential Revision: https://phab.mercurial-scm.org/D7848

sha1dc: initial implementation of Python extension A future change will use this when available to avoid sha1 collision issues until we can get moved to something else. Differential Revision: https://phab.mercurial-scm.org/D7815

sha1dc: import latest version from github After the recent SHA1 news, the attacks are serious enough we should be more proactive. This code will at least allow detection of attacks early. It's already widely deployed in Git. This is git revision 855827c583bc30645ba427885caa40c5b81764d2 of the sha1collisiondetection repo[0], with most of the files omitted. A follow-up change will introduce Python bindings for this code. 0: https://github.com/cr-marcstevens/sha1collisiondetection Differential Revision: https://phab.mercurial-scm.org/D7814

transaction: add a `hasfinalize` method The method allow code to check if an existing callback exists. It allow them to skip potentially expensive setup for a callback. Differential Revision: https://phab.mercurial-scm.org/D7832

changelog: fix the diverted opener to accept more kwargs The current code prevent the use of `atomictemp` file with the changelog opener. I do not see a good reason for this limitation. Differential Revision: https://phab.mercurial-scm.org/D7831

revlog: reorder a conditionnal about revlogio if we are using REVLOGV0, we will not use a rust based index. This small line movement make it clearer. Differential Revision: https://phab.mercurial-scm.org/D7830

rebase: delete seemingly unnecessary needupdate() This seemed to be about checking that the user hasn't updated away when we asked them to resolve merge conflicts. These days we call `cmdutil.checkunfinished()` and refuse to update, so the user shouldn't be able to get into this state. `test-rebase-interruptions.t` actually has some tests where it disables the rebase extension in order to be allowed to do some of these updates. That still passes, but I wouldn't personally haved cared if that failed. Differential Revision: https://phab.mercurial-scm.org/D7825

workingctx: move setparents() logic from localrepo to mirror overlayworkingctx It would be nice to later be able to call `wctx.setparents()` whether `wctx` is a `workingctx` or an `overlayworkingctx`. Differential Revision: https://phab.mercurial-scm.org/D7823