log: display closing-branch nodes as "_" (BC)
In plain `hg log` there is no indication that a commit closes a
branch. You can use hg log --debug, but this is too verbose. A simple
idea copied from thg and other graphical viewers is to display the
node for a closing-branch commit as a horizontal line.
I think this technically is a BC if we consider the graphlog to be
part of the stdout API, but I really can't imagine who the hell is
parsing the graphlog to determine information about commits.
$ hg init
$ echo 123 > a
$ hg add a
$ hg commit -m "first" a
$ mkdir sub
$ echo 321 > sub/b
$ hg add sub/b
$ hg commit -m "second" sub/b
$ cat sub/b
321
$ hg co 0
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ cat sub/b 2>/dev/null || echo "sub/b not present"
sub/b not present
$ test -d sub || echo "sub not present"
sub not present