svn merge --dry-run -r BASE:HEAD .
- http://stackoverflow.com/questions/12964057/svn-preview-update-showing-conflicts-but-update-doesnt-result-in-conflict
- http://stackoverflow.com/questions/182945/how-to-see-what-will-be-updated-from-repository-before-issuing-svn-update-comm/182960
In TRIM, as of 2017-05-28, this is used:
svn merge --dry-run --revision BASE:HEAD . --allow-mixed-revisions
In these two files:
https://sourceforge.net/p/tikiwiki/code/HEAD/tree/trim/src/rclib.php
https://sourceforge.net/p/tikiwiki/code/HEAD/tree/trim/src/appinfo/tiki.php