Commit c41871e542dce9cfb1b5cf1814e17c65c7e04ce4

Edward Thomson 2021-01-07T12:22:08

fetch: test when HEAD points to nonexistent branch When HEAD points to a nonexistent or invalid branch - for example, to `refs/heads/` - the fetch should be permitted to continue, but we should not use it when creating the `for merge` option in the FETCH_HEAD file. (This emulates git's behavior.)