maps: cache hashes() for the revmap This fix caches the hashes() results for revision map. For big repos the revision map can be huge (>30MB) and this fix is saving us some time (~0.7s per every subsequent call) by avoiding reversing rev dictionary multiple times.

#!/bin/sh
. $(dirname $0)/common.sh

for b in `hg branches -aq` ; do
    hg co $b || break
    echo verifying $b
    hg svn verify
done