Re: [PATCH 11/18] branch-diff: add tests

> From: Thomas Rast <tr@thomasrast.ch>
> 
> These are essentially lifted from https://github.com/trast/tbdiff, with
> light touch-ups to account for the new command name.
> 
> Apart from renaming `tbdiff` to `branch-diff`, only one test case needed
> to be adjusted: 11 - 'changed message'.
> 
> The underlying reason it had to be adjusted is that diff generation is
> sometimes ambiguous. In this case, a comment line and an empty line are
> added, but it is ambiguous whether they were added after the existing
> empty line, or whether an empty line and the comment line are added
> *before* the existing emtpy line. And apparently xdiff picks a different