Re: [PATCH] userdiff: skip textconv caching when not in a repository

> Subject: userdiff: skip textconv caching when not in a repository
>
> The textconv caching system uses git-notes to store its cache entries.
> But if you're using "diff --no-index" outside of a repository, then
> obviously that isn't going to work.
>
> Since caching is just an optimization, it's OK for us to skip it.
> However, the current behavior is much worse: we call notes_cache_init()
> which tries to look up the ref, and the low-level ref code hits a BUG(),
> killing the program. Instead, we should notice before setting up the
> cache that it there's no repository, and just silently skip it.