remotefilelog: use list comprehension instead of filter for py3 portability Differential Revision: https://phab.mercurial-scm.org/D5605

tests: fix up uses of xrange in remotefilelog tests for py3 Differential Revision: https://phab.mercurial-scm.org/D5604

tests: add missing b prefixes in remotefilelog-getflogheads.py # skip-blame just b prefixes Differential Revision: https://phab.mercurial-scm.org/D5603

tests: make python oneliner portable to python 3 in remotefilelog test Differential Revision: https://phab.mercurial-scm.org/D5602

remotefilelog: implement __bool__ as well as __nonzero__ for py3 Differential Revision: https://phab.mercurial-scm.org/D5601

remotefilelog: fix logging in retry decorator This still fails with an error about no exception being available to re-raise, but so it goes. Differential Revision: https://phab.mercurial-scm.org/D5600

basepack: avoid 'rbe' mode in Python 3 Differential Revision: https://phab.mercurial-scm.org/D5598

remotefilelog: do file IO in terms of bytes Differential Revision: https://phab.mercurial-scm.org/D5597

rust-cpython: using MissingAncestors from Python code As precedently done with LazyAncestors on cpython.rs, we test for the presence of the 'rustext' module. incrementalmissingrevs() has two callers within the Mercurial core: `setdiscovery.partialdiscovery` and the `only()` revset. This move shows a significant discovery performance improvement in cases where the baseline is slow: using perfdiscovery on the PyPy repos, prepared with `contrib/discovery-helper <repo> 50 100`, we get averaged medians of 403ms with the Rust version vs 742ms without (about 45% better). But there are still indications that performance can be worse in cases the baseline is fast, possibly due to the conversion from Python to Rust and back becoming the bottleneck. We could measure this on mozilla-central in cases were the delta is just a few changesets. This requires confirmation, but if that's the reason, then an upcoming `partialdiscovery` fully in Rust should solve the problem. Differential Revision: https://phab.mercurial-scm.org/D5551

rust: MissingAncestors.basesheads() This new API method on `MissingAncestors` leverages directly the Rust implementation for relative heads of a set, and also lowers the cost of returning the results to Python in the context of discovery. These interchange costs can probably be further reduced by implementing the `partialdiscovery` class in Rust, but that will be investigated in the 5.0 development cycle. Differential Revision: https://phab.mercurial-scm.org/D5584

discovery: using the new basesheads() Our ultimate goal is to switch eventually to a Rust implementation, but this move actually seems to increase the performance in a pure Python build. What follows is a quick measurement done on PyPy on repos prepared with `contrib/discovery-helper.sh 50 100`. Before: ! wall 0.894384 comb 0.890000 user 0.890000 sys 0.000000 (best of 11) ! wall 0.971199 comb 0.970000 user 0.950000 sys 0.020000 (max of 11) ! wall 0.927993 comb 0.925455 user 0.919091 sys 0.006364 (avg of 11) ! wall 0.921619 comb 0.920000 user 0.910000 sys 0.010000 (median of 11) After: ! wall 0.614278 comb 0.610000 user 0.610000 sys 0.000000 (best of 14) ! wall 0.789459 comb 0.790000 user 0.770000 sys 0.020000 (max of 14) ! wall 0.722765 comb 0.720000 user 0.715714 sys 0.004286 (avg of 14) ! wall 0.734448 comb 0.720000 user 0.720000 sys 0.000000 (median of 14) Differential Revision: https://phab.mercurial-scm.org/D5583

ancestor: incrementalmissingancestors.basesheads() This new method will avoid the need to access the `bases` attribute directly in `setdiscovery`, and to prefilter `nullrev` before passing it to the `heads()` revset. Being a method, it can transparently be reimplemented in a Rust (or any native) version. Differential Revision: https://phab.mercurial-scm.org/D5582

rust-cpython: set conversion for MissingAncestors.bases() Also I hope that the separate `py_set()` helper will help transition to proper `PySet` support in `rust-cpython` Took the opportunity to replace explict for loop with iteration and collect(). Differential Revision: https://phab.mercurial-scm.org/D5581

rust: dagop.headrevs() Rust counterparts This introduces two Rust implementations for `mercurial.dagop.headrevs`. The algorithm is identical to the Python version. Depending on the caller, one or the other could be the most practical, or the most performant, by minimizing the amount of memory copy and allocations. Differential Revision: https://phab.mercurial-scm.org/D5580

rust: factorized testing Graphs it will useful to use these outside of `ancestors`, too. Differential Revision: https://phab.mercurial-scm.org/D5579

rust-cpython: moved generic conversion fn out of ancestors module This will allow to use it easily from other submodules Differential Revision: https://phab.mercurial-scm.org/D5578

revset: transparently forward _intlist argument in all case We took a safe approach for the first take, we can get bolder now.

narrow: reuse narrowspec.updateworkingcopy() when narrowing Similar to the previous patch for widening, but here we also need to teach updateworkingcopy() to forcefully delete files that are not recorded in the dirstate as clean. That should be safe because the narrowing command (e.g. `hg tracked --removeinclude`) has already checked that the working copy is clean. Differential Revision: https://phab.mercurial-scm.org/D5511

narrow: reuse narrowspec.updateworkingcopy() when widening The widening of the working copy we do after widening a repo is practically the same as we do in a repo share after the store narrowspec has been changed in a different share. Let's reuse the code for that that we now have in the narrowspec module. Differential Revision: https://phab.mercurial-scm.org/D5510

narrow: move copytonarrowspec() out of setnarrowpats() I think it was a mistake to write the working copy's narrowspec every time the store narrowspec is written. This starts separating those actions. Differential Revision: https://phab.mercurial-scm.org/D5509

narrow: drop now-unnecessary reassignment of repo attributes Differential Revision: https://phab.mercurial-scm.org/D5507

packaging: allow running packaging with custom uid+gid for CentOS rpmbuild in CentOS 7 has a bug causing rpmbuild to fail with "Bad owner/group" if spec or source files are owned by a different user: https://github.com/rpm-software-management/rpm/issues/2 This makes it very annoying to try and build the CentOS RPMs on CentOS with Docker. As an alternative, this change makes it possible to do so, using an environment variable. Differential Revision: https://phab.mercurial-scm.org/D5571

hg-docker: fix Python 3.4 compatibility (for CentOS 7) I realize Mercurial is not targetting Python 3.4 compatibility, but without this change, it's not even possible to build it on CentOS 7 (and I assume the same is true for RHEL 7). Differential Revision: https://phab.mercurial-scm.org/D5570

copies: use node.nullrev instead of literal -1 Differential Revision: https://phab.mercurial-scm.org/D5593

copies: use node.wdirrev instead of inventing another constant for it Differential Revision: https://phab.mercurial-scm.org/D5592

narrow: extract repo property for store narrowmatcher When a repo lock is released, we try to persist the manifest cache. That involves getting the narrowmatcher for the manifestlog. That should not fail if the store and working copy narrowspecs are out of sync. Without this patch, the later patches in this series will fail because of that. Differential Revision: https://phab.mercurial-scm.org/D5508

narrow: copy store narrowspec to working copy immediately We no longer need to delay it until the end of the transaction since we now restore a backup if the transaction aborts. Differential Revision: https://phab.mercurial-scm.org/D5506

narrow: include working copy narrowspec in transaction journal Now that we have separate narrowspecs for the store and the working copy, we need to include both in the transaction journal. Differential Revision: https://phab.mercurial-scm.org/D5505

narrow: make dirstateguard back up and restore working copy narrowspec instead We used to have only one narrowspec for the store and the working copy, but now that we have one narrowspec for each, it seems clear that the dirstateguard was supposed to back up and restore the narrowspec associated with the working copy, not the one associated with the store. clearbackup() (for the store narrowspec) is not needed because the presence of the file in localrepository._journalfiles() takes care of that. Differential Revision: https://phab.mercurial-scm.org/D5504

narrow: include journal.narrowspec in transaction journal We had missed this file before, which led to it lying around after the transaction completed. Differential Revision: https://phab.mercurial-scm.org/D5556