chistedit: use context manager to set verbose ui I'm still not exactly sure why this is necessary -- perhaps setting it unconditionally would leak this setting in chg invocations. Regardless, this would have looked very out of place as compared to how this setting is done everywhere else, so at least for the sake of style, let's be consistent with the rest of the codebase.

setdiscovery: stop limiting the number of local head we initially send In our testing this limitation provides now real gain and instead triggers pathological discovery timing for some repository with many heads. See inline documentation for details. Some timing below: Mozilla try repository, (~1M revs, ~35K heads), discovery between 2 clones with 100 head missing on each side before: ! wall 1.492111 comb 1.490000 user 1.450000 sys 0.040000 (best of 20) ! wall 1.813992 comb 1.820000 user 1.700000 sys 0.120000 (max of 20) ! wall 1.574326 comb 1.573500 user 1.522000 sys 0.051500 (avg of 20) ! wall 1.572583 comb 1.570000 user 1.520000 sys 0.050000 (median of 20) after: ! wall 1.147834 comb 1.150000 user 1.090000 sys 0.060000 (best of 20) ! wall 1.449144 comb 1.450000 user 1.330000 sys 0.120000 (max of 20) ! wall 1.204618 comb 1.202500 user 1.146500 sys 0.056000 (avg of 20) ! wall 1.194407 comb 1.190000 user 1.140000 sys 0.050000 (median of 20) pypy (~100 heads, 317 heads) discovery between clones with only 42 common heads before: ! wall 0.031653 comb 0.030000 user 0.030000 sys 0.000000 (best of 25) ! wall 0.055719 comb 0.050000 user 0.040000 sys 0.010000 (max of 25) ! wall 0.038939 comb 0.039600 user 0.038400 sys 0.001200 (avg of 25) ! wall 0.038660 comb 0.050000 user 0.040000 sys 0.010000 (median of 25) after: ! wall 0.018754 comb 0.020000 user 0.020000 sys 0.000000 (best of 49) ! wall 0.034505 comb 0.040000 user 0.030000 sys 0.010000 (max of 49) ! wall 0.019631 comb 0.019796 user 0.018367 sys 0.001429 (avg of 49) ! wall 0.019132 comb 0.020000 user 0.020000 sys 0.000000 (median of 49) Private repository (~1M revs, ~3K heads), discovery from a strip subset, about 100 changesets to be pulled. before: ! wall 1.837729 comb 1.840000 user 1.790000 sys 0.050000 (best of 20) ! wall 2.203468 comb 2.200000 user 2.100000 sys 0.100000 (max of 20) ! wall 2.049355 comb 2.048500 user 2.002500 sys 0.046000 (avg of 20) ! wall 2.035315 comb 2.040000 user 2.000000 sys 0.040000 (median of 20) after: ! wall 0.136598 comb 0.130000 user 0.110000 sys 0.020000 (best of 20) ! wall 0.330519 comb 0.330000 user 0.260000 sys 0.070000 (max of 20) ! wall 0.157254 comb 0.155500 user 0.123000 sys 0.032500 (avg of 20) ! wall 0.149870 comb 0.140000 user 0.110000 sys 0.030000 (median of 20) Same private repo, discovery between two clone with 500 different heads on each side: before: ! wall 2.372919 comb 2.370000 user 2.320000 sys 0.050000 (best of 20) ! wall 2.622422 comb 2.610000 user 2.510000 sys 0.100000 (max of 20) ! wall 2.450135 comb 2.450000 user 2.402000 sys 0.048000 (avg of 20) ! wall 2.443896 comb 2.450000 user 2.410000 sys 0.040000 (median of 20) after: ! wall 0.625497 comb 0.620000 user 0.570000 sys 0.050000 (best of 20) ! wall 0.834723 comb 0.820000 user 0.730000 sys 0.090000 (max of 20) ! wall 0.675725 comb 0.675500 user 0.628000 sys 0.047500 (avg of 20) ! wall 0.671614 comb 0.680000 user 0.640000 sys 0.040000 (median of 20)

peer: introduce a limitedarguments attributes When set to True, it signal that the peer cannot receive too larges arguments and that algorithm must adapt. This should only be True for http peer that does not support argument passed as "post". This will be useful to unlock better discovery performance in the next changesets. I am using a dedicated argument because this is not really a usual "capabilities" things. An alternative approach would be to adds a "large-arguments" to all peer, but the http peers. That seemed a bit too hacky to me.

verify: also check full manifest validity during verify runs Before this changes, `hg verify` only checked if a manifest revision existed and referenced the proper files. However it never checked the manifest revision content itself. Mercurial is expecting manifest entries to be sorted and will crash otherwise. Since `hg verify` did not attempted a full restoration of manifest entry, it could ignore this kind of corruption. This new check significantly increases the cost of a `hg verify` run. This especially affects large repository not using `sparse-revlog`. For now, this is hidden behind the `--full` experimental flag.

verify: introduce an experimental --full flag The flag currently has no effect, see next changeset for details. We introduce the flag as experimental to keep the freedom of changing our mind on the final UI. Note: this patch highlight a small but in `hg help`. An option section is generated even if no option are visible.

verify: introduce a notion of "level" Some checks are slower than others, to help the user to run the checks he needs, we are about to introduce new flag to select faster vs deeper runs. This put the scaffolding in place to do this.

tests: split out separate test for issue5020 The test was added to the existing setup in 41f6af50c0d8 (merge: fix crash on criss cross merge with dir move and delete (issue5020), 2017-01-31). I'm about to make a change that affects that test and it's much easier to follow if the test case for issue5020 is a separate test case. The separate test case is based on what mpm provided in comment 12 on the issue. `hg diff -r 41f6af50c0d8^ tests/test-merge-criss-cross.t` after this patch is pretty small (besides the added test). It's probably easier for reviewers to look at that than to try to understand the diff itself (I don't understand it). Differential Revision: https://phab.mercurial-scm.org/D6243

tests: avoid a rename/delete conflict when updating in test-narrow-update.t After the upcoming rewrite of mergecopies(), this test would otherwise (accurately) start warning about "inside/f1 was deleted and renamed". Differential Revision: https://phab.mercurial-scm.org/D6254

tests: delete unused function in test-rename-merge2.t Differential Revision: https://phab.mercurial-scm.org/D6253

tests: make merge conflicts explicit in `hg annotate` tests We were using `true` as merge tool. I think it makes the test easier to understand if we make the conflicts explcit. It also papered over a conflict that shouldn't have been a conflict (just a bug in copy tracing). I've marked that "BROKEN". Differential Revision: https://phab.mercurial-scm.org/D6252

narrow: make warning about possibly dirty files respect ui.relative-paths Differential Revision: https://phab.mercurial-scm.org/D6264

merge: forgot to pull before release These two changes should be part of 5.0, but we are fine leaving them out of the RC.

Added signature for changeset 4a8d9ed86475

Added tag 5.0rc0 for changeset 4a8d9ed86475

merge: default into stable for release candidate

debugdiscovery: include the number of heads in all sets We already displayed information about heads of the common set that are either local or remote heads. We now also do so for heads of the common set that are both local and remote heads too. This is useful because various step in the set discovery algorithm have head specific optimizations.

recover: add a --[no-]verify flag For trivial cases, the cost of the verify run after `hg recover` is getting in the way. In addition for very large repositories, the cost is simply too high to be paid, making `hg recover` an unusable commands. We introduce a --verify flag, set by default. If is automatically associated with a --no-verify flag that one can use to skip the verify step. We might consider changing the default behavior in the future. However this is out of scope for this series.

bundle2: handle compression in _forwardchunks _forwardchunks is used to compensate for getbundle protocol deficits. Since it transparently decodes the payload, it also needs to remove the corresponding compression parameter in case the server decides to send one. This the wire protocol part of issue 5990. Differential Revision: https://phab.mercurial-scm.org/D6182

changelog: parse copy metadata if available in extras This lets read back the copy metadata we just started writing. There are still many places left to teach about getting the copy information from the changeset, but we have enough ({file_copies}, specifically) that we can add it now and have some test coverage of it. Differential Revision: https://phab.mercurial-scm.org/D6186

copies: add config option for writing copy metadata to file and/or changset This introduces a config option that lets you choose to write copy metadata to the changeset extras instead of to filelog. There's also an option to write it to both places. I imagine that may possibly be useful when transitioning an existing repo. The copy metadata is stored as two fields in extras: one for copies since p1 and one for copies since p2. I may need to add more information later in order to make copy tracing faster. Specifically, I'm thinking out recording which files were added or removed so that copies._chaincopies() doesn't have to look at the manifest for that. But that would just be an optimization and that can be added once we know if it's necessary. I have also considered saving space by using replacing the destination file path by an index into the "files" list, but that can also be changed later (but before the feature is ready to release). Differential Revision: https://phab.mercurial-scm.org/D6183

revsetbenchmark: add some simpler revset for heads and roots This revset might leverage compiled code in the future so lets start to track them.

repoview: flag `server.view` as experimental Ideally, the non-experimental version of `experimental.extra-filter-revs` will cover the use case for `server.view=immutable` well enough than having to have this dedicated configuration. Since `server.view` is not part of any release, I would prefer to have it marked as experimental to avoid having it to support it for ever.

repoview: move subsettable in a dedicated module The dictionary got moved in `branchmap` to avoid import cycle. However, we are about to needs it in repoview too. So we introduce a now module to define that that mapping.

upgrade: support upgrade to/from zstd storage (issue6088) Now that we have an official config option for a shiny format improvement, we better make it simple to migrate to/from it.

compression: introduce an official `zstd-revlog` requirement This requirement supersedes `exp-compression-zstd`. However, we keep support for the old requirement. Strictly speaking, we do not need to add a new requirement, there are no logic change making "new" repo incompatible with mercurial client using a version that support `exp-compression-zstd`. The choice to introduce a new requirement is motivated by the following: * The previous requirement was explicitly "experimental". Using it by default could confuse users. * adding support for a hypothetical third compression engine will requires new code, and will comes with its own requirement tool. * We won't use it as the default for a while since I do not think we support zstd on all platform. I can imagine we'll gain another (unrelated but on my default) requirement by the time we turn this zstd by default.

compression: only declare revlog support for available engine Even if we know that an engine support revlog compression, the Mercurial process still won't support it if the compression engine is not available.

branchcache: lazily validate nodes in iteritems() This saves ~0.30 sec on creating a new branch on our internal repo. Differential Revision: https://phab.mercurial-scm.org/D6236

branchcache: only iterate over branches which needs to be verified Otherwise we loop over all the branches and call _verifybranch() even if not required. Differential Revision: https://phab.mercurial-scm.org/D6240

branchcache: fix the docstring of _verifybranch() Initially the function was designed to support verifying all branches but later I decided to have a separate function. I forget to remove the doc related to that. Thanks to Yuya for spotting this in review. Differential Revision: https://phab.mercurial-scm.org/D6239

branchcache: don't verify while creating a copy The copy will not be mark as verified, so there is no need to verify nodes. Thanks to Yuya who spotted this while reviewing. Differential Revision: https://phab.mercurial-scm.org/D6238