Re: [PATCH v3 1/2] diff: add --line-prefix option for passing in a prefix

> You might be envisioning a future enhancement where the recursive
> one uses not "-Submodule commit A"/"-Submodule commit B", and not
> "diff A B", but "log -p A...B" in the submodule, and in such a case,
> it might make sense to run "log -p --graph A...B" instead when the
> command the end user run in the superproject asked for "--graph".
> You would use the same "--line-prefix='| | | '" when running the
> "log -p --graph A...B" command in the submodule, so that the output
> for the submodule will go _after_ the graph of the superproject, but
> in that case, the output for the submodule would also include its
> own graph to show the relationship between A and B.  The line-prefix
> must come before that graph part (and also if it is "git log" run in
> the submodule, the same line-prefix must come before each line of
> the log message output).
>