lazymanifest: avoid reading uninitialized memory I got errors running tests with clang UBSAN [1] enabled. One of them is: ``` --- test-dirstate.t +++ test-dirstate.t.err @@ -85,9 +85,115 @@ $ echo "[extensions]" >> .hg/hgrc $ echo "dirstateex=../dirstateexception.py" >> .hg/hgrc $ hg up 0 - abort: simulated error while recording dirstateupdates - [255] + mercurial/cext/manifest.c:781:13: runtime error: load of value 190, which is not a valid value for type 'bool' + #0 0x7f668a8cf748 in lazymanifest_diff mercurial/cext/manifest.c:781 + #1 0x7f6692fc1dc4 in call_function Python-2.7.11/Python/ceval.c:4350 + ....... + SUMMARY: UndefinedBehaviorSanitizer: invalid-bool-load mercurial/cext/manifest.c:781:13 in + [1] $ hg log -r . -T '{rev}\n' 1 $ hg status - ? a ``` While the code is not technically wrong, but switching the condition would make clang UBSAN happy. So let's do it. The uninitialized memory could come from, for example, `lazymanifest_copy` allocates `self->maxlines` items but only writes the first `self->lines` items. [1]: https://clang.llvm.org/docs/UndefinedBehaviorSanitizer.html Test Plan: Run `test-dirstate.t` with UBSAN and it no longer reports the issue. Differential Revision: https://phab.mercurial-scm.org/D1948

unamend: fix command summary line Before this patch, the docstring started with a newline, which led the summary line (shown in e.g. `hg help -c`) to be blank. Differential Revision: https://phab.mercurial-scm.org/D1943

configitems: traverse sections deterministically Otherwise output can be non-deterministic if there are warnings for multiple sections. Differential Revision: https://phab.mercurial-scm.org/D1947

lfs: don't require the .hglfs file to be tracked to control the policy The .hgignore file doesn't need to be tracked, nor does the git equivalent of this file. I'm still a little concerned about the effects of forgetting to commit this file. But the fact that conversions maintain the hashes if only the normal vs external storage changes, should make this less risky.

tests: add a pattern to fix --pure tests Test Plan: ran all tests with and without --pure, everything passed on gcc112. Differential Revision: https://phab.mercurial-scm.org/D1946

streamclone: add a comment about non-publishing being broken with v1 This change was suggested by Gregory Szorc.

streamclone: move requirement update into consumev2 This change was suggested by Gregory Szorc.

streamclone: use readexactly when reading stream v2 Yuya Nishihara pointed out that it is safer.

streamclone: rename '_emit' to '_emit2' for clarity This change was suggested by Gregory Szorc.

help: do not suggest "update --clean ." to cancel uncommitted merge Follows up 41ef02ba329b.

minifileset: note the unsupported file pattern when raising a parse error This was useful in debugging, because I stupidly quoted it out of habit from the command line. This isn't a great example that clearly shows the problem, but I don't know how to improve it. The problem *is* obvious once a complex statement or a clearly bogus string is used.

lfs: don't automatically exclude '.hg*' files from external tracking The only reasons I did this in the first place was because tracking externally seems like it would always be a mistake, and the eol extension does the same thing. Yuya and Jun thought it might be better to not do this[1], so I'll defer to them on this. If a problem with say, .hgtags or .hgeol does arise, it can be added back without breaking existing repos. [1] https://www.mercurial-scm.org/pipermail/mercurial-devel/2018-January/110371.html

lfs: rename {oid} to {lfsoid} Per Yuya, for consistency with {lfspointer}. It might be slightly confusing for there to be {lfsoid} and {lfspointer.oid}. But preventing ambiguity seems more important, and the latter is controlled by the git-lfs spec.

lfs: rename {pointer} to {lfspointer} Per Martin von Zweigbergk's suggestion to keep this unambiguous, for when it is migrated to {files} and friends.

Added signature for changeset 27b6df1b5adb