debugrebuildstate: clarify that rev can't be specified without -r
-r has a default value of '' in the command line. The function default value of
'tip' is thus never used and any attempt at specifying revisions without -r
will fail.
It seems like then intended behavior was that 'hg debugrebuildstate' without
any parameters should set the parents to tip. That would be very confusing now
when the command primarily is used to recover from incorrect stat info.
It is apparently undocumented that '' is the same as '.' ... unless it is
passed in a place where revsets are used.
http://mercurial.selenic.com/bts/issue619
$ hg init
$ echo a > a
$ hg ci -Ama
adding a
$ echo b > b
$ hg branch b
marked working directory as branch b
(branches are permanent and global, did you want a bookmark?)
$ hg ci -Amb
adding b
$ hg co -C 0
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
Fast-forward:
$ hg merge b
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg ci -Ammerge
Bogus fast-forward should fail:
$ hg merge b
abort: merging with a working directory ancestor has no effect
[255]