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