Here is a scenario I am working with: I have a trunk with several revisions that are committed after the branch is created. Let's assume the trunk is currently at revision 140. And let's assume the branch was created from the trunk from revision 100, and currently the HEAD revision in that branch is 136.
What do I need to do to merge up to a specific revision from the branch, e.g. 120 (not the latest -- 136), into the main trunk that contains an up-to some older revision, say, 117 -- not the latest (the three revisions from 118 - 120 are assumed to be commits from the branch)? What I am basically planning to do is to update the trunk to a specific revision from the branch, and discard all the other changes that have been made to the trunk. Does reverting the local copy of trunk to revision 117 and merging it to that specific branch revision (in this case, 120) work, or should I revert the trunk to pre-branch creation (in this case, 100), then merge the branch (revision 120) into the trunk?