relnotes: copy "next" to "5.7" and clear "next" The same procedure as every year^Wcycle. Differential Revision: https://phab.mercurial-scm.org/D9909

relnotes: elaborate on the side effects of hooks having HGPLAIN=1 Differential Revision: https://phab.mercurial-scm.org/D9943

packaging: replace a documentation reference to `python3` on Windows Sadly, there's not `python3.exe` on Windows. Differential Revision: https://phab.mercurial-scm.org/D9937

diff: suppress `merging foo` output lines when performing a merge diff Differential Revision: https://phab.mercurial-scm.org/D9939

diff: add experimental support for "merge diffs" The way this works is it re-runs the merge and "stores" conflicts, and then diffs against the conflicted result. In a normal merge, you should only see diffs against conflicted regions or in cases where there was a semantic conflict but not a textual one. This makes it easier to detect "evil merges" that contain substantial new work embedded in the merge commit. Differential Revision: https://phab.mercurial-scm.org/D8504

rust: use HgError in ConfigError Differential Revision: https://phab.mercurial-scm.org/D9938

rust: Fold find_root and check_requirements into Repo::find Differential Revision: https://phab.mercurial-scm.org/D9906

rhg: Simplify CommandError based on its use Differential Revision: https://phab.mercurial-scm.org/D9905

rust: replace ToString impls with Display ToString is automatically implementing for everything that implements Display, and Display can avoid allocating intermediate strings. Differential Revision: https://phab.mercurial-scm.org/D9904

rust: use HgError in RevlogError and Vfs Differential Revision: https://phab.mercurial-scm.org/D9897

rust: replace RequirementsError with HgError Differential Revision: https://phab.mercurial-scm.org/D9896

rhg: Print an error message in more cases Differential Revision: https://phab.mercurial-scm.org/D9895

rust: Remove DirstateParseError and ListDirstateTrackedFilesError Use HgError instead. Differential Revision: https://phab.mercurial-scm.org/D9894

rust: Replace DirstatePackError with HgError Differential Revision: https://phab.mercurial-scm.org/D9893

rust: Introduce an `HgError` enum for common error cases Differential Revision: https://phab.mercurial-scm.org/D9892

rust: remove three enums that were identical to `RevlogError` Differential Revision: https://phab.mercurial-scm.org/D9877

rhg: replace `map_*_error` functions with `From` impls Differential Revision: https://phab.mercurial-scm.org/D9876

rust: replace trivial `impl From …` with `#[derive(derive_more::From)]` Crate docs: https://jeltef.github.io/derive_more/derive_more/from.html Differential Revision: https://phab.mercurial-scm.org/D9875

rust: remove `FooError` structs with only `kind: FooErrorKind` enum field Use the enum directly as `FooError` instead. Differential Revision: https://phab.mercurial-scm.org/D9874

rhg: centralize parsing of `--rev` CLI arguments This new module will be the place to implement more of the revset language when we do so. Differential Revision: https://phab.mercurial-scm.org/D9873

rust: Remove hex parsing from the nodemap Separating concerns simplifies error types. Differential Revision: https://phab.mercurial-scm.org/D9864

rust: Make NodePrefix allocation-free and Copy, remove NodePrefixRef The `*Ref` struct only existed to avoid allocating `Vec`s when cloning `NodePrefix`, but we can avoid having `Vec` in the first place by using an inline array instead. This makes `NodePrefix` 21 bytes (with 1 for the length) which is smaller than before as `Vec` alone is 24 bytes. Differential Revision: https://phab.mercurial-scm.org/D9863

churn: count lines that look like diff headers but are not Previously, churn cannot count added lines that start with "++ " or removed lines that start with "-- ". Differential Revision: https://phab.mercurial-scm.org/D9929

rust: Exclude empty node prefixes We presumably don’t want `--rev ""` to select every single revision, even though the empty string is a prefix of all strings. Differential Revision: https://phab.mercurial-scm.org/D9862

rust: Simplify error type for reading hex node IDs If a string is not valid hexadecimal it’s not that useful to track the precise reason. Differential Revision: https://phab.mercurial-scm.org/D9861

rust: replace Node::encode_hex with std::fmt::LowerHex This avoids allocating intermediate strings. Differential Revision: https://phab.mercurial-scm.org/D9860

rhg: Build in release mode on CI This follows e73b40c790ec which made tests use the release executable. With e73b40c790ec but not this, tests are skipped on CI because the executable is missing. Differential Revision: https://phab.mercurial-scm.org/D9907

config: use the right API to access git-submodule Differential Revision: https://phab.mercurial-scm.org/D9923

config: use the right API to access template access Preventing direct access to the underlying dict will help a coming refactoring of `config`. Differential Revision: https://phab.mercurial-scm.org/D9922

config: use the right API to access subrepository section Preventing direct access to the underlying dict will help a coming refactoring of `config`. Differential Revision: https://phab.mercurial-scm.org/D9921

config: test priority involving the command line Differential Revision: https://phab.mercurial-scm.org/D9917

config: test priority involving include Differential Revision: https://phab.mercurial-scm.org/D9916

config: add a test for priority when includes are involved Differential Revision: https://phab.mercurial-scm.org/D9915

errors: use InputError for incorrectly formatted dates Differential Revision: https://phab.mercurial-scm.org/D9913

errors: use StateError more in merge module Differential Revision: https://phab.mercurial-scm.org/D9912

errors: use exit code 40 for when a hook fails A hook can be used for checking inputs, state, configuration, security, etc., so it's unclear which of the existing exit codes to use. Let's instead add one specifically for failed hooks. I picked 40. Differential Revision: https://phab.mercurial-scm.org/D9910

context: add missing manifest invalidation after write in overlayworkingctx This was breaking my merge-diff logic that will be in the next patch. Differential Revision: https://phab.mercurial-scm.org/D9908

wix: tell ComponentSearch that it is finding a directory (not a file) This is to fix an issue we've noticed where fresh installations start at `C:\Program Files\Mercurial`, and then upgrades "walk up" the tree and end up in `C:\Program Files` and finally `C:\` (where they stay). ComponentSearch defaults to finding files, which I think means "it produces a string like `C:\Program Files\Mercurial`", whereas with the type being explicitly a directory, it would return `C:\Program Files\Mercurial\` (note the final trailing backslash). Presumably, a latter step then tries to turn that file name into a proper directory, by removing everything after the last `\`. This could likely also be fixed by actually searching for the component for hg.exe itself. That seemed a lot more complicated, as the GUID for hg.exe isn't known in this file (it's one of the "auto-derived" ones). We could also consider adding a Condition that I think could check the Property and ensure it's either empty or ends in a trailing slash, but that would be an installer runtime check and I'm not convinced it'd actually be useful. This will *not* cause existing installations that are in one of the bad directories to fix themselves. Doing that would require a fair amount more understanding of wix and windows installer than I have, and it *probably* wouldn't be possible to be 100% correct about it either (there's nothing preventing a user from intentionally installing it in C:\, though I don't know why they would do so). If someone wants to tackle fixing existing installations, I think that the first installation is actually the only one that shows up in "Add or Remove Programs", and that its registry keys still exist. You might be able to find something under HKEY_USERS that lists both the "good" and the "bad" InstallDirs. Mine was under `HKEY_USERS\S-1-5-18\Software\Mercurial\InstallDir` (C:\), and `HKEY_USERS\S-1-5-21-..numbers..\Software\Mercurial\InstallDir` (C:\Program Files\Mercurial). If you find exactly two, with one being the default path, and the other being a prefix of it, the user almost certainly hit this bug :D We had originally thought that this bug might be due to unattended installations/upgrades, but I no longer think that's the case. We were able to reproduce the issue by uninstalling all copies of Mercurial I could find, installing one version (it chose the correct location), and then starting the installer for a different version (higher or lower didn't matter). I did not need to deal with an unattended or headless installation/upgrade to trigger the issue, but it's possible that my system was "primed" for this bug to happen because of a previous unattended installation/upgrade. Differential Revision: https://phab.mercurial-scm.org/D9891

merge with stable

copyright: update to 2021 Differential Revision: https://phab.mercurial-scm.org/D9885

persistent-nodemap: Fix Rust declarations for Revlog_CAPI signatures Use Rust’s `libc::ssize_t` as the closest match to C’s `Py_ssize_t`. See details in test comment. Going forward we should find a way to have such Rust declarations auto-generated from C headers at build time, or auto-checked against them in a test. Differential Revision: https://phab.mercurial-scm.org/D9901

persistent-nodemap: add test case reproducing a Rust panic Thanks to Mitchell Plamann for reporting this bug. The next commit fixes it. Differential Revision: https://phab.mercurial-scm.org/D9900

copies: fix an incorrect comment in graftcopies() from recent D9802 I don't think the bit about creating a merge in the filelog was correct. Or at least I couldn't find a case where it happened. Differential Revision: https://phab.mercurial-scm.org/D9899

narrow: delete a stale TODO about not sending groups the client already has 2c5835b4246b changed the changegroup generation to not send treemanifests for directories the client had before widening. As that commit mentions, we had already stopped before that commit to send the changelog and filelogs for files the client already had. Differential Revision: https://phab.mercurial-scm.org/D9898

copies: add an devel option to trace all files Filelog based copy tracing only trace copy for file that have been added. This is a trade off between skipping some rare copy case in exchange for avoiding atrocious-to-the-point-of-unusable performance. The changeset centric copy tracing does not need this trade off and naturally trace all copy, include the one involving non-new files. In order to ease the comparison from both algorithm, we add a small devel option to trace copy for all files in the target revisions. Differential Revision: https://phab.mercurial-scm.org/D9796

revlog: prepare pure parser for being overloaded The current class uses module-level variables which don't allow for reusing the current logic for a slightly different revlog version. Differential Revision: https://phab.mercurial-scm.org/D9903

revlog: use a less probable revlog version for backwards compatibility This allows us to define a usable v2. Differential Revision: https://phab.mercurial-scm.org/D9902

clang-format: show required version in skip message This will help people to configure their black Differential Revision: https://phab.mercurial-scm.org/D9890