branching: merge stable into default

stabletailgraph: clarify omission of linear parts in test sorts Those are not interesting and are collapsed using globs. Only the tagged nodes are interesting.

stabletailgraph: omit uninteresting linear parts in test log The test uses tags for the nodes of interest. There is no need to print the linear parts which exist only to force the rank.

stabletailgraph: fix typo in test

stabletailgraph: fix terminology in doc

Added signature for changeset fc445f8abcf9

Added tag 6.4.3 for changeset fc445f8abcf9

relnotes: add 6.4.3

backup: fix issue when the backup end up in a different directory Because of store encoding, we might end up with the backup in a different directory than the initial copy (for example if the backup path make it cross the 120 char limit). This can create crash, especially since 6.4 where backup are used during revlog split. Making sure the directory exists fixes these crash We added a test covering this case. Strictly speaking, this has always been broken, however the new code in 6.4 triggers it more easily.

vfsproxy: inherit the `createmode` attribute too It is an important part of the API when creating directory. We will need it in the next changeset.

revlog: test more complex file pattern for revlog split There have been a report of failure while splitting revlog. The file name involved was important. The pattern involved here are not problematic, but it help to setup the machinery to test multiple files, the actual fix and problematic file will arrive in a later changeset.

repo-upgrade: write new requirement before upgrading the dirstate This will prevent a small race condition where another hg process still believes the repo is dirstate-v1 during the upgrade process. This is good to have, but it is not a proper fix for the underlying problem. There is code that assumes a requirement means a usage, e.g. having the `generaldelta` requirement would imply *all* revlogs to use general delta, but it's not true, it simply means that the repository advertises to the client it needs to understand `generaldelta` in order to read the repo. In the case of the dirstate, having the requirement *technically* should always be the same as using dirstate-v2, since there is only one dirstate and requirements should be as minimal as possible. However, we should not assume this and make the code more robust in a future patch (series).

perf: introduce a `perf::stream-locked-section` command This command benchmark the initial part of a stream clone, where the repository is locked.

transaction: tr._names are actually bytes, use byte string to join them Looks like this is never checked in the tests? But trying e.g. `print(tr)` by hand before this change would give: TypeError: sequence item 0: expected str instance, bytes found Looks like tr._names are always bytes (although this isn't actually enforced, but maybe at some point it will at least be type checked e.g. by pytype).

nix: add nix-defined package and devel env (flake) This adds a Nix Flake which defines: - package recipies to build and run Mercurial (C, C+Rust variants), - a meta package to run the test suite in an isolated sandbox, - a development environment with some tools (notably Python and the Black formatter, pinned to match the CI). Python is pinned to the recommended version. The Rust toolchain is a fairly recent one provided by the Nixpkgs channel. It is not yet pinned to the same version as the "reference" Debian package, but this does not seem to cause any issue. Example usage of local commands are provided in the `flake.nix` file. Once merged, it should also be possible to pull and run directly from the source repository directly with something like: `nix run hg+https://foss.heptapod.net/mercurial/mercurial-devel?ref=TOPIC&dir=contrib/nix' -- version`

hgignore: ignore nix result symlink

tests: add test ignore list for nix Some tests cannot run properly in the nix sandbox. This adds a list of tests to ignore when running in that context.

ui: keep the progress bar around when writing if stdout is not a tty

rhg: correctly relativize copy source path

rhg: don't print copy source when --no-status is passed

tests: add test for status copy source formatting

fix: highlight the required configuration and behavior of the fixer tools The problem is that `hg help fix` didn't mention *how* to configure the tools, and while I knew that `{rootpath}` existed in the configuration, I missed that the tools require reading content from stdin. (I configured `gofmt` to use `{rootpath}`, and that had the effect of squashing all changes in a file at `.` into the first commit and emptying that content from its descendants.) Basically all this does is put a pointer in the default (command level) help to the extension level help that mentions the configuration, and moves the extension level help that documents reading from stdin and writing to stdout to the top to give it more prominence. The last sentence is adjusted a bit to reflect the new location.

debug-delta: add minimal documentation for `devel.bundle-delta` option So the next person won't have to grep the code to know what it is doing.

delta-find: simply code that is now never invoqued without general delta Finish early in on-general delta case mean a lot of code can assume that general delta is not enabled.

delta-find: add a simple safeguard to prevent bad non-general-delta This make it easier to catch request to build delta that does not make sense in the general delta world. It seems better to raise a programming error than to corrupt the repository.

delta-find: never do anything fancy when general delta is off Without general delta, the only option is to do a delta against the previous revision in the revlog, or to do a full snapshot. So no need to dive into the more complicated logic. This prevent Mercurial to misbehave when applying remote deltas when `pulled-delta-reuse-policy` was set to "try-base" or "forced" and would produce and store invalid deltas. We add an associated tests to make sure this scenario is covered by tests. There are more code to cleanup after this, but I what to keep the fixing patch simple.

delta-find: assume the target-rev if not specified This will be useful in the next patch, but I am putting it in its own commit to make sure we can easily bisect any subtle side effect. (none are expected, but still)

tests: in filterpyflakes, tolerate non-ascii file contents

comments: fix spelling

chg: set CHGHG before connecting to command server cf4d2f31 (!523) changed chg to set `CHGHG` itself when spawning a new command server, in order to ensure that the path to the `hg` executable would be checked during server validation. (This is useful when chg is built with `HGPATHREL`). However, that change broke chg because it failed to set `CHGHG` before trying to connect to an existing command server. This means that if `CHGHG` is not present in the environment, chg will always spawn a new command server, entirely negating the point of chg. This breakage wasn't initially caught because of the difficulty of writing automated tests with the `HGPATHREL` feature enabled, which meant the change was only tested manually to make sure that it fixed the problem with `HGPATHREL` that prompted the change. In practice, this functionality is only really useful when chg is built with `HGPATHREL`, so I considered wrapping it in an `#ifdef` to preserve the old behavior by default. However, this makes it hard to write tests since one would have to explicitly set `HGPATHREL=1` when running `run-tests.py` (which is why the original change lacked tests). It would be great if there were a way of testing features that are gated behind conditional compilation.