hg-stable: Changelog

copies: avoid calling matcher if matcher.always() When storing copy information in the changesets (experimental.copies.read-from=changeset-only), this patch speeds up hg debugpathcopies FENNEC_58_0_2_BUILD1 FIREFOX_59_0b8_BUILD2 from 5.9s to 4.7s. At the start of this series (b162229e), that command took 18min. Differential Revision: https://phab.mercurial-scm.org/D6422

copies: avoid unnecessary copying of copy dict When storing copy information in the changesets, this patch speeds up hg debugpathcopies FENNEC_58_0_2_BUILD1 FIREFOX_59_0b8_BUILD2 from 11s to 5.9s. That command takes 6.2s when storing copy information in filelogs. Differential Revision: https://phab.mercurial-scm.org/D6421

copies: don't filter out copy targets created on other side of merge commit If file X is copied to Y on one side of merge and the other side creates Y (no copy), we would not mark that as copy. In the changeset-centric pathcopies() version, that was done by checking if the copy target existed on the other branch. Even though merge commits are pretty uncommon, it still turned out to be too expensive to load the manifest of the parents of merge commits. In a repo of mozilla-unified converted to storing copies in changesets, about 2m30s of `hg debugpathcopies FIREFOX_BETA_59_END FIREFOX_BETA_60_BASE` is spent on this check of merge commits. I tried to think of a way of storing more information in the changesets in order to cheaply detect these cases, but I couldn't think of a solution. So this patch simply removes those checks. For reference, these extra copies are reported from the aforementioned command after this patch: browser/base/content/sanitize.js -> browser/modules/Sanitizer.jsm testing/mozbase/mozprocess/tests/process_normal_finish_python.ini -> testing/mozbase/mozprocess/tests/process_normal_finish.ini testing/mozbase/mozprocess/tests/process_waittimeout_python.ini -> testing/mozbase/mozprocess/tests/process_waittimeout.ini testing/mozbase/mozprocess/tests/process_waittimeout_10s_python.ini -> testing/mozbase/mozprocess/tests/process_waittimeout_10s.ini Since these copies were created on one side of some merge, it still seems reasonable to include them, so I'm not even sure it's worse than filelog pathcopies(), just different. Differential Revision: https://phab.mercurial-scm.org/D6420

copies: do full filtering at end of _changesetforwardcopies() As mentioned earlier, pathcopies() is very slow when copies are stored in the changeset. Most of the cost comes from calling _chain() for every changeset, which is slow because it needs to read manifests. It needs to read manifests to be able to filter out copies that are were created in one commit and then deleted. (It also filters out copies that were created from a file that didn't exist in the starting revision, but that's a fixed revision across calls to _chain(), so it's much cheaper.) This patch changes from _chainandfilter() to just _chain() in the main loop in _changesetforwardcopies(). It instead removes copies that have subsequently been removed by using ctx.filesremoved(). We thus rely on that to be fast. It timed this command in mozilla-unified: hg debugpathcopies FIREFOX_59_0b3_BUILD2 FIREFOX_BETA_59_END It took 18s before and 1.1s after. It's still faster when copy information is stored in filelogs: 0.70s. It also still gets slow when there are merge commits involved, because we read manifests there too. We'll deal with that later. Differential Revision: https://phab.mercurial-scm.org/D6419

rust-filepatterns: add comment about Windows path handling As I replied to the Phabricator message, this is wrong. And I even suspect it wouldn't compile because of multiple type mismatches. I think, in Rust where type system is rock solid, we can live with UTF-8 strings except for the bottom storage layer and the top UI/command layer. We'll still have to get around undecodable characters not to be lost, but I think it's okay to drop such filenames from match result if they don't match in UTF-8 world, not in Latin-1 world.