dirstate-v2: Change the on-disk format when the requirement is enabled For now, the format is the same except with an additional marker at the start. This marker is redundant: for existing repositories it is `.hg/requires` that determines which format to use. For new repositories, it is the new `format.exp-dirstate-v2` config. There is no upgrade or downgrade so far. Most of the changes are about plumbing a boolean through layers of APIs to indicate which format should be used. Differential Revision: https://phab.mercurial-scm.org/D10719

dirstate-v2: Update the expected output of some tests for new requirement Fix most test failures (except in test-narrow-debugrebuilddirstate.t and test-upgrade-repo.t) caused by the new entry in config or in .hg/requires when running `run-tests.py --extra-config-opt format.exp-dirstate-v2=1` There is no CI so far for this configuration. Differential Revision: https://phab.mercurial-scm.org/D10718

tests: More cleanly separate expected hexdump output There are more lines that differ than are in common, and dirstate-v2 will complicate that further. Differential Revision: https://phab.mercurial-scm.org/D10717

dirstate-v2: Add a new experimental `exp-dirstate-v2` repository requirement This requirement is added to `.hg/requires` when creating a new repository if Rust extensions are enabled and the `format.exp-dirstate-v2` config is set. Nothing yet changes based on this requirement, but its mere presence affects some tests (for example if they print `.hg/requires`). The next two changesets update tests’ expected outputs accordingly. There is no CI so far that enables this configuration. Differential Revision: https://phab.mercurial-scm.org/D10716

urlutil: provide some information about "bad url" when processing `pushurl` It appears pushurl only support `<proto>://` entries. This is not obvious and can lead to obscure error. We make the error less obscure as a start.. Differential Revision: https://phab.mercurial-scm.org/D10455

revset: document the `outgoing` behavior if the path resolve to multiple urls Differential Revision: https://phab.mercurial-scm.org/D10454

multi-urls: document the feature We have a feature lets make it visible to people. Differential Revision: https://phab.mercurial-scm.org/D10453

multi-urls: add a boolean suboption that unlock path specification as list When this option is set, a list of patch can be specifed as value for `[paths]` entries. For the command who support it, this behave the same as providing multiple destination of the command line. Differential Revision: https://phab.mercurial-scm.org/D10452

urlutil: move url "fixing" at the time of `ui.paths` initialization Doing such fixing at the time is simpler and will be necessary to deal with urls list in a sane manner. It also reduce the size of fix-config which is always better. I wish we could get ride of the hackish way to pass the root around, I suspect that the `root` variable could be stored as part of the config value, along side the source. However getting to the end of this `root` business is a far too large detours to make now. The test change to `tests/test-hgrc.t` and `test-config.t` are expectied since we are not longer altering the config itself, but the way it is interpreted when building path. This seems more correct. I also added a couple of test call to `test-config.t` and `test-globalopts.t` to clarify that the expanding process is properly happening a the right time. Differential Revision: https://phab.mercurial-scm.org/D10451

rewriteutil: add pointer to help text when rewrite would cause divergence The evolve extension's version of the hint has this pointer. I missed it when I moved it to core. Differential Revision: https://phab.mercurial-scm.org/D10723

changelogv2: use a dedicated on disk format for changelogv2 We drop two unused entry. This is mostly a proof of concept before starting to actually rework the format. Differential Revision: https://phab.mercurial-scm.org/D10667

revlog: do not call Rust code if the index is not compatible with it This will avoid hitting the TypeError we defined in the previous changesets. This is the simplest fix but not the most elegant. Ideally we would teach the Rust code to use any kind of revlog. However this is an adventure for another time. Differential Revision: https://phab.mercurial-scm.org/D10666

revlog: signal which revlog index are compatible with Rust Otherwise, Rust may treat python object like `cindex` object, leading to trouble. The new attribute is an integer because I expect we might need a flag field in the future. As a start we get the rust code to raise a clear TypeError. We will use the information in a smarter way in the next changesets. Differential Revision: https://phab.mercurial-scm.org/D10665

revlog: pass around the `rev` we deal with when packing/unpacking entry This will help code to compute some flag on the fly. Differential Revision: https://phab.mercurial-scm.org/D10664

changelogv2: use a dedicated version number If we want to change the format, we need a new version number. We start with that. Differential Revision: https://phab.mercurial-scm.org/D10663

changelogv2: `copies-side-data` now implies `changelogv2` To store information about file changes and copies only requires sidedata support for the changelog. So we only enables `changelogv2`. This is less impactful and should help us to ship the changeset centric copy tracing sooner. Differential Revision: https://phab.mercurial-scm.org/D10662

changelogv2: allow upgrade from and to this format Differential Revision: https://phab.mercurial-scm.org/D10661

changelogv2: introduce a "changelogv2" feature Right now, this means using revlogv2, but only for the changelog. We will have the format more unique in future changesets. Differential Revision: https://phab.mercurial-scm.org/D10660

revlogv2: drop the code related to inlined revlogv2 Tevlogv2 will not use inlined revlog. As a result we can drop the associated code. Differential Revision: https://phab.mercurial-scm.org/D10659

revlogv2: no longer attempt to use inline for new revlog revlogv2 steered away for the inline feature. Differential Revision: https://phab.mercurial-scm.org/D10658

sidedata: use the "feature" to detect that sidedata are enabled This is more versatile than relying on the revlogv2 requirements. Differential Revision: https://phab.mercurial-scm.org/D10657

revlog: compress sidedata when doing "post-pull" sidedata update All path writing sidedata are now using compression (when appropriate). Differential Revision: https://phab.mercurial-scm.org/D10656

revlog: compress sidedata in `_writeentry` When appropriate we store the sidedata in a compressed form. Differential Revision: https://phab.mercurial-scm.org/D10655

revlog: apply compression mode while reading sidedata Right now, we only store things as PLAIN, but we are ready for some compression now. Future changeset will start using some. Differential Revision: https://phab.mercurial-scm.org/D10654

revlog: introduce a compression mode for sidedata in the revlog index We will use this for compression for the sidedata payload. Differential Revision: https://phab.mercurial-scm.org/D10653

revlog: implement a "default compression" mode The revlog docker is now storing a default compression engine. When a chunk use that compression, a dedicated mode is used in the revlog entry and we can directly route it to the right decompressor. We should probably make PLAIN and DEFAULT mode the only available mode for revlogv2, but this is something for later. Differential Revision: https://phab.mercurial-scm.org/D10652

revlog: add a `_get_decompressor` method This logic is non-trivial and we will need to reuse it. Differential Revision: https://phab.mercurial-scm.org/D10651

revlog: introduce a plain compression mode That mode is simple it means the chunk contains uncompressed data and can be used directly. Differential Revision: https://phab.mercurial-scm.org/D10650

revlog: use an intermediate variable for `data` in `_chunk` This will help us to dispatch this to the right decompressor. Differential Revision: https://phab.mercurial-scm.org/D10649

revlogv2: preserve the compression mode on disk The value is still the same and still not treated, but now it exists one disk. Differential Revision: https://phab.mercurial-scm.org/D10648