discovery: add new set-based discovery Adds a new discovery method based on repeatedly sampling the still undecided subset of the local node graph to determine the set of nodes common to both the client and the server. For small differences between client and server, it uses about the same or slightly fewer roundtrips than the old tree-based discovery. For larger differences, it typically reduces the number of roundtrips drastically (from 150 to 4, for instance). The old discovery code now lives in treediscovery.py, the new code is in setdiscovery.py. Still missing is a hook for extensions to contribute nodes to the initial sample. For instance, Augie's remotebranches could contribute the last known state of the server's heads. Credits for the actual sampler and computing common heads instead of bases go to Benoit Boissinot.

debugbuilddag: use memctx for speed This drops the options to run arbitrary shell commands within commits and the option to create a file that gets appended to in every revision. It now supports to not write file data at all, which is very fast for generating a pure 00changelog.i (useful for discovery tests, for instance). Timings for 1000 linear nodes: * Old `hg debugbuilddag -o '+1000'` took 4.5 secs. * New `hg debugbuilddag -o '+1000'` takes 2 secs. * New `hg debugbuilddag '+1000'` takes 0.8 secs. (The last one creates only 00changelog.i).

localrepo: reuse parent manifest in commitctx if no files have changed This speeds up the in-memory version of debugbuilddag that I'm working on considerably for the case where we want to build just a 00changelog.i (for discovery tests, for instance). There are a couple of test changes because node ids in tests have changed. The changes to the patch names in test-mq-qdelete.t were required because they could collide with nodeid abbreviations and newly actually do (patch "c" collides with id "cafe..." for patch "b").

bundlerepo: fix and improve getremotechanges Fixes the regression where incoming could show local changes introduced by rev 72c84f24b420.

hgrc.5: mention new 'case collision' handling for ui.portablefilenames

win32: remove obsolete bookmarks and parentrevspec extensions from mercurial.ini

bundlerepo: drop struct

bisect: fix indent level

share: create 'hgrc' using an opener, like clone

backout 3a3584967a93 - the "unreachable code" was apparently not unreachable All tests repeatedly passes with 3a3584967a93 on some machines, but on other machines it regularly causes failure in test-mv-cp-st-diff.t, such as: @@ -203,6 +203,7 @@ - working to root: --rev 0 M a + M x/x A b a