mergetools: alphabetize the config settings This will make it easier to identify differences with the TortoiseHg config file. It was simply piped through `sort`, and then the spacing and comments restored into the proper place. The `UltraCompare` config was positioned such that the sort is case insensitive- it's the only camelcase config in here. Differential Revision: https://phab.mercurial-scm.org/D9620

share: properly copy cache files when cloning from a share If a is shared to b and b cloned to c, the old code would look directly under b/.hg for the cache directory and not use the cachevfs layer to pick the members from a/.hg/cache. Adjust variable names and comments to reflect that the function is used for more than just the branchmap cache. Differential Revision: https://phab.mercurial-scm.org/D9598

tests: workaround for a flaky test Differential Revision: https://phab.mercurial-scm.org/D9597

revlog: support none compression revlog files had uncompressed revlog entries support since forever, but it wasn't selectable or exposed explicitly. It is occassionally useful for performance testing as it avoids the latency of zlib or zstd. It also has the nice side effect of providing a non-default compression engine out-of-the-box. Differential Revision: https://phab.mercurial-scm.org/D9572

errors: raise InputError on recursive template definition Differential Revision: https://phab.mercurial-scm.org/D9602

errors: raise StateError when push fails because it creates new heads I decided to raise `StateError` here because the local and remote repos are in an incompatible state. I think remote errors (exit code 100) should be when something goes wrong on the remote and there's nothing the user can do. Differential Revision: https://phab.mercurial-scm.org/D9391

errors: raise InputError on early parse error in dispatch I didn't think this would have any effect on the tests, but it does because the catching in `scmutil.callcatch()` still happens. That's because `dispatch` passes in the function that includes the parsing as an argument to that function. I initially used `ConfigError` here but Matt Harbison convinced me to use `InputError`. I think that makes sense since error is not in a config file. Differential Revision: https://phab.mercurial-scm.org/D9387

errors: raise more specifc errors from narrowcommands Differential Revision: https://phab.mercurial-scm.org/D9386

errors: use detailed exit code 50 for StorageError This is done as part of https://www.mercurial-scm.org/wiki/ErrorCategoriesPlan. Differential Revision: https://phab.mercurial-scm.org/D9601

errors: raise InputError if an ambiguous revision id prefix is used It's long bothered me that we include the "00changelog.i" part in a message to the user. This fixes that along with the exit code. Differential Revision: https://phab.mercurial-scm.org/D9600

localrepo: delete obsolete comment about `prefix in repo` raising exception We dropped support for `prefix in repo`, where `prefix` is a hex prefix, in 8b86acc7aa64 (context: drop support for looking up context by ambiguous changeid (API), 2018-04-28), after having deprecated it a while before that. These days you get a `ProgrammingError` instead if you pass in a short nodeid. Differential Revision: https://phab.mercurial-scm.org/D9599

node: import symbols explicitly There is no point in lazy importing mercurial.node, it is used all over the place anyway. So consistently import the used symbols directly. Fix one file using symbols indirectly via mercurial.revlog. Differential Revision: https://phab.mercurial-scm.org/D9480

branching: merge with stable

debugdiscovery: fix swapped heads and roots Patch provided without comment… Differential Revision: https://phab.mercurial-scm.org/D9566

debugdiscovery: display the number of roundtrip used This is a good metric of the complexity of a discovery process. Differential Revision: https://phab.mercurial-scm.org/D9565

copies: make calculating lazy for dir move detection's "addedfiles" The information calculated here was only needed if (a) --debug was specified, or (b) a directory move was plausibly detected. With tree manifests (especially in my pathological repo and with our custom setup), pre-calculating the `u1` and `u2` can be quite slow, and it's not even necessary in many cases. Let's delay calculating it until we know it's actually necessary. This should have no observable differences in output. ### Performance I ran a rebase command in my pathological repo, rebasing two nodes across several public phase commits, but where no directory copies exist in any of the paths I'm tracking. #### Before ``` Time (mean ± σ): 3.711 s ± 0.061 s [User: 0.3 ms, System: 1.5 ms] Range (min … max): 3.640 s … 3.827 s 10 runs ``` #### After ``` Time (mean ± σ): 868.3 ms ± 10.1 ms [User: 0.5 ms, System: 1.2 ms] Range (min … max): 856.6 ms … 883.6 ms 10 runs ``` Differential Revision: https://phab.mercurial-scm.org/D9567

mergetools: add new conflict marker format with diffs in I use 3-way conflict markers. Often when I resolve them, I manually compare one the base with one side and apply the differences to the other side. That can be hard when the conflict marker is large. This patch introduces a new type of conflict marker, which I'm hoping will make it easier to resolve conflicts. The new format uses `<<<<<<<` and `>>>>>>>` to open and close the markers, just like our existing 2-way and 3-way conflict markers. Instead of having 2 or 3 snapshots (left+right or left+base+right), it has a sequence of diffs. A diff looks like this: ``` ------- base +++++++ left a -b +c d ``` A diff that adds one side ("diff from nothing") has a `=======` header instead and does not have have `+` prefixed on its lines. A regular 3-way merge can be viewed as adding one side plus a diff between the base and the other side. It thus has two ways of being represented, depending on which side is being diffed: ``` <<<<<<< ======= left contents on left ------- base +++++++ right contents on -left +right >>>>>>> ``` or ``` <<<<<<< ------- base +++++++ left contents on -right +left ======= right contents on right >>>>>>> ``` I've made it so the new merge tool tries to pick a version that has the most common lines (no difference in the example above). I've called the new tool "mergediff" to stick to the convention of starting with "merge" if the tool tries a regular 3-way merge. The idea came from my pet VCS (placeholder name `jj`), which has support for octopus merges and other ways of ending up with merges of more than 3 versions. I wanted to be able to represent such conflicts in the working copy and therefore thought of this format (although I have not yet implemented it in my VCS). I then attended a meeting with Larry McVoy, who said BitKeeper has an option (`bk smerge -g`) for showing a similar format, which reminded me to actually attempt this in Mercurial. Differential Revision: https://phab.mercurial-scm.org/D9551

diff: deprecate -r option The new `--from`/`--to` options should be enough to support all the uses cases and are easier to understand, so there is no reason that I'm aware of to use `-r` anymore. Differential Revision: https://phab.mercurial-scm.org/D9564

diff: update synopsis to use --from/--to instead of -r Differential Revision: https://phab.mercurial-scm.org/D9563

diff: describe behavior by using --from/--to instead of varying revision count I very recently updated the documentation to prefer `--from`/`--to` over `-r`, but I missed the plain-text description of how the command behaves when given different numbers of revisions (I guess I just scanned the text for "-r"). This patch fixes that. Differential Revision: https://phab.mercurial-scm.org/D9562

histedit: adjust comment describing `edit` action for clarity Differential Revision: https://phab.mercurial-scm.org/D9561

histedit: tweak `edit` message to try and guide users to our workflow histedit predates evolve, so it drops you on an _uncommitted_ version of the commit you're amending/splitting, which is in contrast to git which expects you to use `git commit --amend` (I think - I'm basing this on internal bug reports). My hope is that this output will guide users a little more towards the expected workflow. Differential Revision: https://phab.mercurial-scm.org/D9560

procutil: don't assign stdin to None, use os.devnull instead It will be painful to take care of procutil.stdin being None everywhere. Thanks to Yuya who recommended it.

dispatch: move IOError handling and flushing of streams to `dispatch()` Instead of patching both dispatch code and commandserver code, we directly handle this in `dispatch.dispatch()`. Thanks to Yuya who recommended this.