Could we have a way to automatically compare two svn (or GIT or any other scm) repo branches and/or tags to get a sense of how many lines of code was actually modified/added?
Yes, this is possible... depending on your definition of "automatic". cloc can report the lines of code that were modified/added between two directories (or archive files, or one of each). The part that remains for you to do is add automation to export/clone/check out the two repo branches and save the results to two directories, then invoke cloc on these two directories.
cloc can't compute diffs given URLs pointing to two repos.
If you would like to refer to this comment somewhere else in this project, copy and paste the following link:
Yes, this is possible... depending on your definition of "automatic". cloc can report the lines of code that were modified/added between two directories (or archive files, or one of each). The part that remains for you to do is add automation to export/clone/check out the two repo branches and save the results to two directories, then invoke cloc on these two directories.
cloc can't compute diffs given URLs pointing to two repos.