merge: fix small bug with a failed merge across a rename
If $HGMERGE wasn't able to fix the conflicts, we wouldn't copy
f to fd, and util.set_exec wouldn't find the file.
adding base
abort: cannot delete applied patch c
Now at: b
a
b
a
b
series
status
Now at: a
a
b
series
status
1 New patch: a
0 base
abort: cannot delete revision 3 above applied patches
f
4 New patch: f
3 New patch: e
2 New patch: d
1 New patch: a
0 base