largefiles: fall back to the original for change/delete conflicts The largefiles merge code (currently) does not handle change/delete conflicts. So fall back to regular filemerge in that case. Making this code handle change/delete conflicts is left as an exercise for the future.

mergestate.add: store absentfilectxes as nullhex This is the most natural way to represent these files. We also need to make sure we don't try to store these files in the merge store.

mergestate._resolve: handle change/delete conflicts We will represent a deleted file as 'nullhex' in the in-memory and on-disk merge states. We need to be able to create absentfilectxes in that case, and delete the file from disk rather than try to write it out.

filemerge: don't try to copy files known to be absent We set 'back' to None in this case, so we need to handle that as well.

hgweb: use absolute_import

hgweb: import wsgicgi at top level There should be no practical reason to delay the import of wsgicgi.

hgweb: import BaseHTTPServer as module at top level This will avoid future warning spotted by the import checker.

hgweb: do not import hgweb_mod.hgweb and .makebreadcrumb as symbol It will be enforced by the import checker.

filemerge: don't try using external tools on change/delete conflicts This is mostly for completeness' sake -- the current code shouldn't get to this point.

filemerge: don't attempt to premerge change/delete conflicts This is mostly for completeness' sake -- at the moment we don't support any tools for change/delete conflicts that would do a premerge.

filemerge._mergecheck: add check for change/delete conflicts Merge tools that perform an actual 3-way merge can't handle change/delete conflicts. This adds a check for that.

filemerge._picktool: only pick from nomerge tools for change/delete conflicts For --tool or HGMERGE, we could have either: (a) proceeded with the particular tool, then failed the merge. (b) chosen to prompt regardless. We're explicitly choosing (b) here, because it's effectively what we've been doing so far and helps maintain an easier-to-use interface. However, in future patches we're going to change the default selection from 'pick changed version' to 'leave unresolved'. That fixes most of the brokenness involved with choice (b).

filemerge: add support for change/delete conflicts to the ':prompt' tool We haven't added the 'leave unresolved' option yet -- that will come in a future patch.

filemerge: add support for change/delete conflicts to the ':other' merge tool This, along with the previous patch to the :local merge tool, covers the full matrix of change/delete conflicts.

filemerge: add support for change/delete conflicts to the ':local' merge tool This covers two of the four cases of change/delete conflicts -- in an upcoming patch we'll make :other cover the other two.

merge.mergestate: compute dirstate action In upcoming patches we're going to queue these actions up to be applied to the dirstate at the end.