hgweb: load revcount + 1 entries to fill nextentry in log page (issue5972) "revcount + 1" is moved to the call site to make it clearer.

scmutil: avoid quadratic membership testing (issue5969) tr.changes['revs'] is an xrange, which has an O(n) __contains__ implementation. The `rev not in newrevs` lookup a few lines below will therefore be O(n^2) if all incoming changesets are public. This issue isn't present on @ because 45e05d39d9ce introduced a custom type implementing an xrange primitive with O(1) contains and switched tr.changes['revs'] to be an instance of that type. We work around the problem on the stable branch by casting the xrange to a set. This is a bit hacky because it requires allocating memory to hold each integer in the range. But we are already holding the full set of pulled revision numbers in memory multiple times (such as in `tr.changes['phases']`). So this is a relatively minor problem. This issue has been present since the phases reporting code was introduced in the 4.7 cycle by eb9835014d20. This change should be reverted/ignored when stable is merged into default. On the mozilla-unified repository with 483492 changesets, `hg clone` time improves substantially: before: 1843.700s user; 29.810s sys after: 461.170s user; 29.360s sys

phases: drop dead code in `newheads` There are new code earlier in the function achieving the same result. Spotted by Yuya Nishihara.

phases: fix `nullid` reference in newheads Spotted by Yuya Nishihara.

beautifygraph: don't warn about busted terminal if HGPLAIN is set This was breaking some automation for users that discovered the extension and turned it on. Differential Revision: https://phab.mercurial-scm.org/D4338

merge: do not delete untracked files silently (issue5962) 37450a122128, 2a774cae3a03, and 656ac240f392 weren't enough to prevent data loss. No unknown "files" weren't deleted before 7a8a16f8ea22, "context: also consider path conflicts when clearing unknown files."

perf: fix typo in perfphasesremote()

remotephase: avoid full changelog iteration (issue5964) Changeset 88efb7d6bcb6 introduced a performance regression by triggering a full ancestors walk. This changeset reworks this logic so that we no longer walk down the full changelog. The motivation for 88efb7d6bcb6, issue5939, is still fixed. mercurial compared to a draft repository ---------------------------------------- 8eeed92475d5: 0.012637 seconds 88efb7d6bcb6: 0.202699 seconds (x16) 46da52f4b820: 0.215551 seconds (+6%) this code: 0.008397 seconds (-33% from base) The payload size reduction we see in `test-bookmarks-pushpull.t` comes from a more aggressive filter of nullid and is harmless.

remotephase: fast path newheads computation in simple case (issue5964) Changeset 88efb7d6bcb6 fixed the logic of `phases.newheads` but greatly regressed its performance (up to many order of magnitude). The first step to fix the regression is to exit early when there is no work to do. If there are no heads to filter or not roots to filter them, we don't have to do any work. This fixes the regression when talking to an all public changeset. The performance is even better than before. pypy, compared to an all public repo ------------------------------------ 8eeed92475d5: 0.005758 seconds 88efb7d6bcb6: 0.602517 seconds (x104) this code: 0.001508 seconds (-74% from base) mercurial compared to an all public repo ---------------------------------------- 8eeed92475d5: 0.000577 seconds 88efb7d6bcb6: 0.185316 seconds (x321) this code: 0.000150 seconds (-74% from base) The performance of newheads, when actual computations are required, is fixed in the next changeset.

perf: add a perfphasesremote command This command measure the time we spend analysing remote phase during push and pull and display some information relevant to this computation. The `test-contrib-perf.t` expected output has to be updated but I do need these module for this perf command.