Fixes to "hg heads -r FOO": Make it actually work (undefined variable 'rev'; allow to pass a rev parameter). repo.branchlookup() doesn't need a copy of heads because it doesn't modify it. Use None as default argument to heads() instead of nullid. Doc string PEPification.

#!/bin/sh

mkdir test
cd test
echo foo>foo
hg init
hg addremove
hg commit -m 1
hg verify
hg serve -p 20059 > /dev/null &
sleep 1 # wait for server to be started
cd ..

hg clone http://localhost:20059/ copy
cd copy
hg verify
hg co
cat foo
hg manifest
hg pull

kill $!