maps: add the "branchmaxrevnum" method to RevMap Iterating the RevMap can be very expensive for large repos. To prevent future code from iterating the possibly huge RevMap causing performance issues, it's a good idea to clean all iterating code outside RevMap. This patch adds a method used by "get_parent_svn_branch_and_rev". In the future, we will have a SqliteRevMap, which will have an efficient implementation for this query, and it will disable "__iter__" to prevent future performance issues.

#!/bin/sh
#
# Generate renames.svndump
#

mkdir temp
cd temp

mkdir project-orig
cd project-orig
mkdir trunk
mkdir branches
cd ..

svnadmin create testrepo
svnurl=file://`pwd`/testrepo
svn import project-orig $svnurl -m "init project"

svn co $svnurl project
cd project/trunk
# Create and remove a file, hgsubversion does not like
# empty repositories
echo a > a
svn add a
svn ci -m "add a"
svn rm a
svn ci -m "remove a"
cd ../..

svnadmin dump testrepo > ../emptyrepo.svndump