ci: remove py2-rust support Nobody cares about this very narrow usecase, and py2 support is over by July 1st. This helps with the CI load, and removes some flakiness.

relnotes: add release notes for 6.1.2

docs: use proper rst markup for preformatted blocks The multiple lines were re-flowed to a single line, both in man page and html.

test-dirstate: print something when the check is skipped This makes a programming error obvious in cases when it should not be skipped Differential Revision: https://phab.mercurial-scm.org/D12602

test-dirstate: fix detection of Rust environment variable The Rust path never actually worked. This change also improves clarity of the comment. The next change will ensure we print something when this check fails. Differential Revision: https://phab.mercurial-scm.org/D12601

rust-dirstate-v2: fix the unused bytes counter when rewriting the dirstate As per the previous patch, the counter was incorrectly carried over from the old docket when it should be reset for a complete rewrite. Differential Revision: https://phab.mercurial-scm.org/D12594

rust-dirstate-v2: show `unused_bytes` counter is not reset on total rewrite This was picked up by @aalekseyev when doing unrelated debugging. The Rust implementation was never resetting this counter, so a brand new file would carry over the old counter. As I write this, my counter is a supposed 7389089 unused bytes for a total of 170978 bytes in the data file. Feel free to post your own high score. Differential Revision: https://phab.mercurial-scm.org/D12593

test-dirstate: use new `--docket` flag to get the data uuid This is more robust. Differential Revision: https://phab.mercurial-scm.org/D12592

debugcommands: remove `debugdirstateignorepatternhash` This is replaced by the more complete `--docket` option to `debugstate`. Differential Revision: https://phab.mercurial-scm.org/D12591

dirstate-v2: add flag to `debugstate` to print docket information This is useful information that we don't easily have access to currently, unless you speak fluent xxd. This replaces `debugdirstateignorepatternshash`, which I'll remove in the next changeset. Differential Revision: https://phab.mercurial-scm.org/D12590

doc: use an absolute path in sys.path to work around a python DLL loading bug This bug[1] was causing the zstd entry under "Available Compression Engines" to be omitted from the documentation for some versions of python3. I could upgrade, but past upgrades have broken venvs and clobbered installed packages. It's a trivial workaround, so there's no sense in leaving this subtle issue. It was flushed out by changing the module policy here from 'allow' to 'c', and seeing this error: ImportError: DLL load failed while importing parsers: The parameter is incorrect. [1] https://github.com/python/cpython/issues/87271 Differential Revision: https://phab.mercurial-scm.org/D12599

rhg: fix dirstate-v2 data file removal system In D12581 I introduced logic to remove the previous dirstate-v2 data file after a new one is created (and its corresponding docket), but the logic was flawed. I fixed it and made it simpler to understand by gather all logic in a single expression. Differential Revision: https://phab.mercurial-scm.org/D12586

rhg: use `Command::exec` instead of `Command::status` `rhg` is supposed to be a transparent executable, using a subprocess defeats that purpose. See inline comments for more details. This also introduces the `which` crate to check if the fallback executable actually exists to help debugging (plain `execve` doesn't give much information). The error code 253 is used to signify that the fallback is not found, but may mean in the future that it is otherwise invalid if we start being more specific. Differential Revision: https://phab.mercurial-scm.org/D12578

commit: don't use hard-coded `.hg/last-message.txt` path in error message Whoever wrote D8463 just used a hard-coded path to `.hg/last-message.text` instead of using the relative path that was already available in the `msgfn` variable (and used just a few lines up in related message). Let's fix that. Differential Revision: https://phab.mercurial-scm.org/D12585

branching: merge stable into default This also added the small fix need in Rust tests for the new `DirstateMap::pack_v2` API change in stable.

rust-dirstate-v2: clean up previous data file after the docket is written This was overlooked before and caused many data files to keep living forever. We could potentially consider adding a random cleanup of them in case they slipped through one day. Differential Revision: https://phab.mercurial-scm.org/D12581

rust-dirstate-v2: save proper data size if no new data on append This is currently only triggered with the tests ran with `--rhg` without `--rust`, by "luck", there probably always was something to write, like an mtime when also using Rust extensions alongside `rhg`. Differential Revision: https://phab.mercurial-scm.org/D12580

amend: move "return None for removed files" into block handling filestoamend This is just a small logic cleanup from D12573, no change in behavior. Differential Revision: https://phab.mercurial-scm.org/D12576

rust-dirstatemap: remove unused helper from the old API Differential Revision: https://phab.mercurial-scm.org/D12541

rust-status: stop using `state()` in the dispatch logic Let's use the new API. Differential Revision: https://phab.mercurial-scm.org/D12540

rust-status: stop using `state()` in `handle_normal_file` Let's use the new API Differential Revision: https://phab.mercurial-scm.org/D12539

rust-dirstatemap: stop using `state()` in the cache logic Let's use the new API Differential Revision: https://phab.mercurial-scm.org/D12538

rust-dirstatemap: stop using `.state` in `is_from_other_parent` This is a deprecated API and will be removed one day. Differential Revision: https://phab.mercurial-scm.org/D12537

rust-dirstate-entry: add `modified` method This will also be used in other places later in the series. Differential Revision: https://phab.mercurial-scm.org/D12536

rust: remove use of `EntryState` in `DirsMultiset` Let's use the new API. Differential Revision: https://phab.mercurial-scm.org/D12535

rust: use `entry.tracked()` directly This is the new API Differential Revision: https://phab.mercurial-scm.org/D12534

rust-hg-cpython: remove use of `EntryState` Let's use the new API Differential Revision: https://phab.mercurial-scm.org/D12533

rust-dirstatemap: use a checked sub instead of a potentially underflowing one This was missed in 2593873cda0f Differential Revision: https://phab.mercurial-scm.org/D12532

rust-dirstatemap: add simpler version of `get_node_mut` This will help reduce code and footgun potential for simpler callers. Differential Revision: https://phab.mercurial-scm.org/D12531

rust-dirstatemap: use `get_node_mut` instead or `get_or_insert_node` This (along with the docstring), makes it more obvious that we're not expecting to insert a node here. This is less prone to bugs in later refactorings. Differential Revision: https://phab.mercurial-scm.org/D12530