copy: simplify inner copy
- save dirstate lookup and exists check
- do all fs work inside a single dryrun clause
- move unlinking into inner copy section
- move target dir creation
- eliminate undelete mess
- fix a bug on mv a -> b -> a after merge
% create source repository
adding a
% fork source repository
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
adding b
% update source repository
% merge repositories
pulling from ../t2
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files (+1 heads)
(run 'hg heads' to see heads, 'hg merge' to merge)
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
M b
% rename b as c
A c
R b
% rename back c as b
M b