Add revlog.parentrevs function.
This allows one to walk the revision graph using only revision numbers,
which can be faster than using revision hashes, especially for
RevlogNG, where the parents of a revision are stored as revision
numbers.
#!/bin/sh
hg init test
cd test
echo foo > foo
hg add foo
hg commit -d '0 0' -m commit-1
echo foo >> foo
hg commit -d '1 4444444' -m commit-3
hg commit -d '1 15.1' -m commit-4
hg commit -d 'foo bar' -m commit-5
hg commit -d ' 1 4444' -m commit-6
hg commit -d '111111111111 0' -m commit-7
echo bar > bar
hg add bar
rm bar
hg commit -d "1000000 0" -m commit-8 2>&1 | sed -e "s:/.*\(/test/.*\):...\1:"
exit 0