Without copies/renames, merges source names are 1:1 with their
targets. Copies and renames introduce the possibility that there will
be two merges with the same input but different output. By doing the
copy to the destination name before the merge, the actual merge
becomes 1:1 again, and no source is the input to two different merges.
- add a preliminary scan to applyupdates to do copies
- for the merge action, pass the old name (for finding ancestors) and
the new name (for input to the merge) to filemerge
- eliminate the old post-merge copy
- lookup file contents from new name in filemerge
- pass new name to external merge helper
- report merge failure at new name
- add a test
record copies in dirstate even if rename was remote
this lets us record it properly at commit
teach checkfilemerge about copies, including merge cases
pull old copy code out of commit
extend rename-merge1 test to show file index
findcopies: ignore files renamed on both branches
applyupdates: change remove flag to move
recordupdates: record copy actions, including local moves and deletions
This adds findcopies, which detects merge-relevant copies between
files in a pair of manifests back to the merge ancestor.
While the merge code invokes the copy detection routine, it does not
yet use the result.
