Development is a bad example, but for the current state, not considering
"0.10.2 will be out soon", the existence of -svn on a system was more
than just for development.
When you read the old threads you can see that release
tarballs are just svn revisions with no additional changes.
With this recent change, maybe out-of-tree is a better place.
Fyi, I tried with most recent head and tests no longer fail it seems.