Issue a warning if "-r ." is used with two working directory parents.
Rationale for not aborting instead:
The first parent is usually more important as it is the local branch
during a merge and commands like 'hg diff' and 'hg diff -r.' behave still
identically (except for the warning of course).
Added a test for log -r. with one and two parents.
import os
from mercurial import hg, ui, commands
u = ui.ui()
repo = hg.repository(u, 'test1', create=1)
os.chdir('test1')
repo = hg.repository(u, '.') # FIXME: can't lock repo without doing this
# create 'foo' with fixed time stamp
f = file('foo', 'w')
f.write('foo\n')
f.close()
os.utime('foo', (1000, 1000))
# add+commit 'foo'
repo.add(['foo'])
repo.commit(text='commit1', date="0 0")
print "workingfilectx.date =", repo.workingctx().filectx('foo').date()