update: add comments and test cases for updating across branches
Add comment to merge.py:update() showing various cases of 'hg update': to a
descendant, crossing named branches, and crossing branches within a named
branch; with no option, -c or -C; with or without uncommitted changes; and
with or without a specific revision. Add tests for all of these cases.
#!/usr/bin/env python
#
# Copyright 2009 Matt Mackall <mpm@selenic.com> and others
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2, incorporated herein by reference.
"""prints repr(sys.stdin) but preserves newlines in input"""
import sys
print repr(sys.stdin.read())[1:-1].replace('\\n', '\n'),