rust-nodemap: add binding for `nodemap_data_all` Differential Revision: https://phab.mercurial-scm.org/D8158

rust-nodemap: use proper Index API instead of using the C API Differential Revision: https://phab.mercurial-scm.org/D8157

rust-nodemap: add utils for propagating errors This also updates the copyright notice Differential Revision: https://phab.mercurial-scm.org/D8156

rust-nodemap: add utils to create `Node`s from Python objects Differential Revision: https://phab.mercurial-scm.org/D8155

rust-index: add `append` method to cindex/Index This will be used by `MixedIndex` in a later patch. Differential Revision: https://phab.mercurial-scm.org/D8154

rust-index: moved constructor in separate impl block with the upcoming addition of the nodemap logic, it's going to become more complicated. Being in the separate impl block has the advantage to be subject to rustfmt, whereas code inside macro calls isn't. Differential Revision: https://phab.mercurial-scm.org/D8153

revlog: using two new functions in C capsule from Rust code We expose `index_length` and `index_node` in the C capsule, so that the Rust representation of the C index can implement the `RevlogIndex` trait. Because our `Node` is actually a one-field struct, we have to decorate it for direct FFI exchange with the C `char*` It would be a good thing to get a length from the C layer, but doing so right now would probably interfere with the upcoming changes that will happen there for the hash length. Differential Revision: https://phab.mercurial-scm.org/D8152

nodemap: refresh the persistent data on nodemap creation The logic to read the data and validate the docket are still in python, so we need to "help" whatever compiled code live in the index to refresh it. Otherwise clearing the cache could lead to an expensive full recomputation and disk update even when the persisted data are still valid. Differential Revision: https://phab.mercurial-scm.org/D8174

tests: check availability of pyflakes by trying to import pyflakes module Since e397c6d74652, we use the pyflakes module instead of the pyflakes executable. As was pointed out during the review, the hghave check can be rewritten to try to import the pyflakes module instead of spawning a new subprocess.

nodemap: deal with the "debugupdatecache" case using a "fake" transaction We are going to need more and more methods of the transaction. So lets change approach. The `hg debugupdatecache` case do not need a transaction, because has the repositories locked, but is not adding any "store" data to it. Differential Revision: https://phab.mercurial-scm.org/D8186

changelog: change the implementation of `_divertopener` During a transaction, new data to the changelog index are "diverted". The previous implementat ways pretty basic, we need something better to be able to use the changelog vfs fully during transaction. (eg: accessing the vfs options). Differential Revision: https://phab.mercurial-scm.org/D8185

nodemap: test that an outdated nodemap can catch up If the persistent nodemap does not contains all revision that the index contains, this is should be detected and dealt with. We add a test for this case. Differential Revision: https://phab.mercurial-scm.org/D8183

nodemap: document the docket attributes More documentation rarely hurts. Differential Revision: https://phab.mercurial-scm.org/D8182

git: key off `git` in .hg/requires rather than separate file Differential Revision: https://phab.mercurial-scm.org/D8265

git: correctly handle p1() on dirstate when underlying git repo is empty This shows up in my next change, which ends up making an empty git repo and then running hg. Differential Revision: https://phab.mercurial-scm.org/D8271

rust: clean remains of direct-ffi code Since b55bec1ea972, the cext entry poitn have been removed, so we drop the code for consistency.

heptapod-ci: use the new `--rust/--no-rust` flag to run the tests

run-tests: add option for running with and without Rust extensions This provide a simple and clear way to run the test with or without rust.

run-tests: rename "pure" variable to setup_opts There are more useful flag than just `--pure`. We clarify the variable name before adding more options.

setup-rust: add a --no-rust flag This new flag will make sure the rust extension will not be build. If neither `--rust` nor `--no-rust` is specified the `HGWITHRUSTEXT` is used.

cext: drop the WITH_RUST block These were used by the `direct-ffi` mode that just got dropped.

setup: use printf instead of print Yuya Nishihara pointed `printf` to me, so I will respect the cargo cult.

git: don't fail import when pygit2 is not install `test-duplicateoptions.py` was failing on py2 for be because I didn't have pygit2 installed. It failed because we depend on pygit2 at import time. This patch makes it so we successfully load the git extension even if pygit2 doesn't exist -- we just won't be able to use it in that case. Differential Revision: https://phab.mercurial-scm.org/D8268

hghave: add a check for pygit2 This will make it easy to use availability of pygit2 as in conditions such as `#if pygit2` and `(pygit2 !)`. It also makes it a little clearer why the test case skipped (when that happens). Differential Revision: https://phab.mercurial-scm.org/D8267

localrepo: add git extension to autoextensions list Differential Revision: https://phab.mercurial-scm.org/D8266

gitlog: implement __iter__ on changelog This allows `hg phase --force --draft -r .` to work, for example. Differential Revision: https://phab.mercurial-scm.org/D8264

gitlog: fix embarassing bug that prevented log from showing correct parents We had the correct parents in the database, but the changelog was always returning p1 for all parents. Oops. Differential Revision: https://phab.mercurial-scm.org/D8263

git: add readfast() method to manifest Mysteriously, on a different system a handful of things don't work without this, including log. This is especially odd to be because log works in the test. In any event, it's legal for readfast() to just return read(), so that's what we do. Differential Revision: https://phab.mercurial-scm.org/D8262

git: make {shortest()} return shortest *unique* prefix It used to return the prefix of the specified length as long as the full node was unique (i.e. always). Differential Revision: https://phab.mercurial-scm.org/D8256

git: skeleton of a new extension to _directly_ operate on git repos This is based in part of work I did years ago in hgit, but it's mostly new code since I'm using pygit2 instead of dulwich and the hg storage interfaces have improved. Some cleanup of old hgit code by Pulkit, which I greatly appreciate. test-git-interop.t does not cover a whole lot of cases, but it passes. It includes status, diff, making a new commit, and `hg annotate` working on the git repository. This is _not_ (yet) production quality code: this is an experiment. Known technical debt lurking in this implementation: * Writing bookmarks just totally ignores transactions. * The way progress is threaded down into the gitstore is awful. * Ideally we'd find a way to incrementally reindex DAGs. I'm not sure how to do that efficiently, so we might need a "known only fast-forwards" mode on the DAG indexer for use on `hg commit` and friends. * We don't even _try_ to do anything reasonable for `hg pull` or `hg push`. * Mercurial need an interface for the changelog type. Tests currently require git 2.24 as far as I'm aware: `git status` has some changed output that I didn't try and handle in a compatible way. This patch has produced some interesting cleanups, most recently on the manifest type. I expect continuing down this road will produce other meritorious cleanups throughout our code. Differential Revision: https://phab.mercurial-scm.org/D6734