copy: add option to unmark file as copied To unmark a file as copied, the user currently has to do this: hg forget <dest> hg add <dest> The new command simplifies that to: hg copy --forget <dest> That's not a very big improvement, but I'm planning to also teach `hg copy [--forget]` a `--at-rev` argument for marking/unmarking copies after commit (usually with `--at-rev .`). Differential Revision: https://phab.mercurial-scm.org/D8029

nodemap: introduce an option to use mmap to read the nodemap mapping The performance and memory benefit is much greater if we don't have to copy all the data in memory for each information. So we introduce an option (on by default) to read the data using mmap. This changeset is the last one definition the API for index support nodemap data. (they have to be able to use the mmaping). Below are some benchmark comparing the best we currently have in 5.3 with the final step of this series (using the persistent nodemap implementation in Rust). The benchmark run `hg perfindex` with various revset and the following variants: Before: * do not use the persistent nodemap * use the CPython implementation of the index for nodemap * use mmapping of the changelog index After: * use the MixedIndex Rust code, with the NodeTree object for nodemap access (still in review) * use the persistent nodemap data from disk * access the persistent nodemap data through mmap * use mmapping of the changelog index The persistent nodemap greatly speed up most operation on very large repositories. Some of the previously very fast lookup end up a bit slower because the persistent nodemap has to be setup. However the absolute slowdown is very small and won't matters in the big picture. Here are some numbers (in seconds) for the reference copy of mozilla-try: Revset Before After abs-change speedup -10000: 0.004622 0.005532 0.000910 × 0.83 -10: 0.000050 0.000132 0.000082 × 0.37 tip 0.000052 0.000085 0.000033 × 0.61 0 + (-10000:) 0.028222 0.005337 -0.022885 × 5.29 0 0.023521 0.000084 -0.023437 × 280.01 (-10000:) + 0 0.235539 0.005308 -0.230231 × 44.37 (-10:) + :9 0.232883 0.000180 -0.232703 ×1293.79 (-10000:) + (:99) 0.238735 0.005358 -0.233377 × 44.55 :99 + (-10000:) 0.317942 0.005593 -0.312349 × 56.84 :9 + (-10:) 0.313372 0.000179 -0.313193 ×1750.68 :9 0.316450 0.000143 -0.316307 ×2212.93 On smaller repositories, the cost of nodemap related operation is not as big, so the win is much more modest. Yet it helps shaving a handful of millisecond here and there. Here are some numbers (in seconds) for the reference copy of mercurial: Revset Before After abs-change speedup -10: 0.000065 0.000097 0.000032 × 0.67 tip 0.000063 0.000078 0.000015 × 0.80 0 0.000561 0.000079 -0.000482 × 7.10 -10000: 0.004609 0.003648 -0.000961 × 1.26 0 + (-10000:) 0.005023 0.003715 -0.001307 × 1.35 (-10:) + :9 0.002187 0.000108 -0.002079 ×20.25 (-10000:) + 0 0.006252 0.003716 -0.002536 × 1.68 (-10000:) + (:99) 0.006367 0.003707 -0.002660 × 1.71 :9 + (-10:) 0.003846 0.000110 -0.003736 ×34.96 :9 0.003854 0.000099 -0.003755 ×38.92 :99 + (-10000:) 0.007644 0.003778 -0.003866 × 2.02 Differential Revision: https://phab.mercurial-scm.org/D7894

rust-dirstatemap: directly return `non_normal` and `other_entries` This cleans up the interface which I previously thought needed to be uglier than in reality. No performance difference, simple refactoring. Differential Revision: https://phab.mercurial-scm.org/D8121

copy: rename `wctx` to `ctx` since it will not necessarily be working copy Differential Revision: https://phab.mercurial-scm.org/D8032

copy: rewrite walkpat() to depend less on dirstate I want to add a `hg cp/mv -r <rev>` option to mark files as copied/moved in an existing commit (amending that commit). The code needs to not depend on the dirstate for that. Differential Revision: https://phab.mercurial-scm.org/D8031

merge with stable

pathutil: resurrect comment about path auditing order It was removed at 51c86c6167c1, but expensive symlink traversal isn't the only reason we should walk path components from the root.

rust-dirstatemap: remove additional lookup in dirstate.matches We use the same trick as the Python implementation Differential Revision: https://phab.mercurial-scm.org/D7119

rust-nodemap: insert method In this implementation, we are in direct competition with the C version: this Rust version will have a clear startup advantage because it will read the data from disk, but the insertion happens all in memory for both. Differential Revision: https://phab.mercurial-scm.org/D7795

recover: don't verify by default The reason is: - it's not that hard to trigger interrupted transactions: just run out of disk space - it takes forever to verify on large repos. Before --no-verify, I told people to C-c hg recover when the progress bar showed up. Now I tell them to pass --no-verify. - I don't remember a single case where the verification step was useful This is technically a change of behavior. Perhaps this would be better suited for tweakdefaults? Differential Revision: https://phab.mercurial-scm.org/D7972

context: use manifest.find() instead of two separate calls I noticed this while debugging an extension that's implementing the manifest interface. Always nice to save a function call. Differential Revision: https://phab.mercurial-scm.org/D8109

rust-matchers: implement `visit_children_set` for `FileMatcher` As per the removed inline comment, this will become useful in a future patch in this series as the `IncludeMatcher` is introduced. Differential Revision: https://phab.mercurial-scm.org/D7914

manifest: move matches method to be outside the interface In order to adequately smoke out any legacy consumers of the method, we rename it to _matches so it's clear that it's class-private. To my amazement, all consumers of this method really only wanted matching filenames, not a full filtered manifest. Differential Revision: https://phab.mercurial-scm.org/D8085

tags: use modern // operator for division Fixes a test on Python 3. # skip-blame only correcting a division operator, not a substantive change Differential Revision: https://phab.mercurial-scm.org/D8108

tags: fix some type confusion exposed in python 3 # skip-blame just b-prefix and %-format cleanup, no meaningful change Differential Revision: https://phab.mercurial-scm.org/D8107

rebase: remove some now-unused parent arguments Differential Revision: https://phab.mercurial-scm.org/D7829

rebase: remove some redundant setting of dirstate parents Since we're now setting the dirstate parents to its correct values from the beginning (right after `merge.update()`), we usually don't need to set them again before committing. The only case we need to care about is when committing collapsed commits. So we can remove the `setparents()` calls just before committing and add one only for the collapse case. Differential Revision: https://phab.mercurial-scm.org/D7828

rebase: don't use rebased node as dirstate p2 (BC) When rebasing a node, we currently use the rebased node as p2 in the dirstate until just before we commit it (we then change to the desired parents). This p2 is visible to the user when the rebase gets interrupted because of merge conflicts. That can be useful to the user as a reminder of which commit is currently being rebased, but I believe it's incorrect for a few reasons: * I think the dirstate parents should be the ones that will be set when the commit is created. * I think having two parents means that you're merging those two commits, but when rebasing, you're generally grafting, not merging. * When rebasing a merge commit, we should use the two desired parents as dirstate parents (and we clearly can't have the rebased node as a third dirstate parent). * `hg graft` (and `hg update --merge`) sets only one parent and `hg rebase` should be consistent with that. I realize that this is a somewhat large user-visible change, but I think it's worth it because it will simplify things quite a bit. Differential Revision: https://phab.mercurial-scm.org/D7827

rebase: stop relying on having two parents to resume rebase I'm about to make it so we don't have two parents when a rebase is interrupted (unless we're just rebasing on a merge commit). The code for detecting if we're resuming a rebase relied on having two parents, so this patch rewrites that to instead set a boolean when we resume. Note that `self.resume` in the new condition implies `not self.inmemory` (rebase cannot be resumed in memory), so that's why that part can be omitted. Differential Revision: https://phab.mercurial-scm.org/D7826

graphlog: use '%' for other context in merge conflict This lets the user more easily find the commit that is involved in the conflict, such as the source of `hg update -m` or the commit being grafted by `hg graft`. Differential Revision: https://phab.mercurial-scm.org/D8043

tests: add `hg log -G` output when there are merge conflicts The next commit will change the behavior for these. I've used slightly different commands in the different tests to match the surrounding style. Differential Revision: https://phab.mercurial-scm.org/D8042

revset: add a revset for parents in merge state This may be particularly useful soon, when I'm going to change how `hg rebase` sets its parents during conflict resolution. Differential Revision: https://phab.mercurial-scm.org/D8041

tests: add test of rebase with conflict in merge commit It doesn't seem like we had any tests of this. I think it's pretty weird that the two parents we're merging are not the working copy parents during the conflict resolution. Differential Revision: https://phab.mercurial-scm.org/D7824

rebase: always be graft-like, not merge-like, also for merges Rebase works by updating to a commit and then grafting changes on top. However, before this patch, it would actually merge in changes instead of grafting them in in some cases. That is, it would use the common ancestor as base instead of using one of the parents. That seems wrong to me, so I'm changing it so `defineparents()` always returns a value for `base`. This fixes the bad behavior in test-rebase-newancestor.t, which was introduced in 65f215ea3e8e (tests: add test for rebasing merges with ancestors of the rebase destination, 2014-11-30). The difference in test-rebase-dest.t is because the files in the tip revision were A, D, E, F before this patch and A, D, F, G after it. I think both files should ideally be there. Differential Revision: https://phab.mercurial-scm.org/D7907

nodemap: update the index with the newly written data (when appropriate) If we are to use mmap to read the nodemap data, and if the python code is responsible for the IO, we need to refresh the mmap after each write and provide it back to the index. We start this dance without the mmap first. Differential Revision: https://phab.mercurial-scm.org/D7893

nodemap: never read more than the expected data amount Since we are tracking this number we can use it to detect corrupted rawdata file and to only read the correct amount of data when possible. Differential Revision: https://phab.mercurial-scm.org/D7892

nodemap: write new data from the expected current data length If the amount of data in the file exceed the expect amount, we will overwrite the extra data. This is a simple way to be safer. Differential Revision: https://phab.mercurial-scm.org/D7891

nodemap: double check the source docket when doing incremental update In theory, the index will have the information we expect it to have. However by security, it seems safer to double check that the incremental data are generated from the data currently on disk. Differential Revision: https://phab.mercurial-scm.org/D7890