merge: suggest 'hg up -C .' for discarding changes, not 'hg up -C'
Without specifying the parent revision of the working copy, users will
update to tip, which is most likely the other head they were trying to
merge, not the revision they were at before the merge.
test that a commit clears the merge state.
$ hg init repo
$ cd repo
$ echo foo > file
$ hg commit -Am 'add file'
adding file
$ echo bar >> file
$ hg commit -Am 'append bar'
create a second head
$ hg up -C 0
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ echo baz >> file
$ hg commit -Am 'append baz'
created new head
failing merge
$ HGMERGE=internal:fail hg merge
0 files updated, 0 files merged, 0 files removed, 1 files unresolved
use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon
$ echo resolved > file
$ hg resolve -m file
$ hg commit -m 'resolved'
resolve -l, should be empty
$ hg resolve -l
test crashed merge with empty mergestate
$ mkdir .hg/merge
$ touch .hg/merge/state
resolve -l, should be empty
$ hg resolve -l