commit: fix rest syntax of examples This fixes the formatting of help/commit page and silence test-gendoc.t.

ui: optionally ignore sub-options from configitems() For convenience.

ui: add method to return option and all sub-options Apparently ":" has been blessed as a generic separator for options and sub-options. We formalize this by introducing an API for obtaining an option and all its sub-options. This will be used in a subsequent patch for declaring sub-options for [paths].

revlog: don't consider nullrev when choosing delta base In the most complex case, we try using the incoming delta base, then we try both parents, and then we try the previous revlog entry. If none of these result in a good delta, we natually use the null revision as base. However, we sometimes consider the nullrev before we have exhausted our other options. Specifically, when both parents are null, we use the nullrev as delta base if it produces a good delta (according to _isgooddelta()), and we fail to try the previous revlog entry as delta base. After 20a9226bdc8a (addrevision: use general delta when the incoming base delta is bad, 2015-12-01), it can also happen for non-merge commits when the incoming delta is not good. The Firefox repo (from many months back) shrinks a tiny bit with this patch: from 1.855GB to 1.830GB (1.4%). The hg repo itself shrinks even less: by less than 0.1%. There may be repos that get larger instead. This undoes the unexplained test change in 20a9226bdc8a.

revlog: make calls to _isgooddelta() consistent We always want to call _isgooddelta() before accepting a delta. We mostly call the function right after building the delta, but not always. Instead, we have an extra call at the end of the big code block. Let's make it consistent, so we call _isgooddelta() right after builddelta() and exactly once per delta. That also lets us rely on "delta is None" to mean we didn't find a good delta.

revlog: clarify which revision is added to 'tested' when using cached delta The tested delta revisions are added to the 'tested' set. These are the same revisions we pass to builddelta(). However, in one case, we add builddelta(rev)[3] to the set intead of adding 'rev' itself. In that particular case, that element is the same as the function's input revision (because self._generaldelta is true), so the effect is the same. Still, let's just add the function's input revision to avoid confusing future readers.

revlog: remove unused variable 'chainlen'

commit: adjust the quoting in the examples to be Windows friendly We should probably avoid strong quotes around command line args in the examples, since cmd.exe doesn't recognize them, and it will surprise a user who cargo cults them. I don't see a way to make a rule for this, since strong quoting is OK inside command line args, like within revsets.

wireproto: config options to disable bundle1 bundle2 is the new and preferred wire protocol format. For various reasons, server operators may wish to force clients to use it. One reason is performance. If a repository is stored in generaldelta, the server must recompute deltas in order to produce the bundle1 changegroup. This can be extremely expensive. For mozilla-central, bundle generation typically takes a few minutes. However, generating a non-gd bundle from a generaldelta encoded mozilla-central requires over 30 minutes of CPU! If a large repository like mozilla-central were encoded in generaldelta and non-gd clients connected, they could easily flood a server by cloning. This patch gives server operators config knobs to control whether bundle1 is allowed for push and pull operations. The default is to support legacy bundle1 clients, making this patch backwards compatible.

dockerlib: short form for non-unique uid/gid for CentOS 5 compat (issue4977) CentOS 5 does not support '--non-unique', but does support the short '-o'.

exchange: standalone function to determine if bundle2 is requested This will be used in a subsequent patch.

wireproto: add docstring for wirepeer

commit: add some help examples (issue4963) Includes documenting --date now, which resolves the above issue.

changegroup: restate file linknode callback using generator expressions I think this is slightly clearer, and it nicely avoids an extra nested function.

changegroup: clean up file lookup function One case is basically degenerate, so just extract it and make the function clearer.

changegroup: remove one special case from lookupmflinknode In the fastpathlinkrev case, lookupmflinknode was a very complicated way of saying mfs.__getitem__, so let's just get that case out of our way so it's easier to understand what's going on.