Re: [PATCH v2 02/18] Add a new builtin: branch-diff

Jeff King [off-list ref] writes:

One of the things I don't like about "git branch --diff" is that this
feature is not _just_ about branches at all.

I actually wouldn't be that much against the word "branch" in
"branch-diff" on the ground that we are typically not feeding
branches to the command (we are feeding two ranges, and one endpoint
of each range typically gets expressed using branch name), as we
have a precedent in "show-branch", for example, that often takes
branches but does not have to.

It's really "diff-history" or something, I think. That's not very
catchy, but I think the best name would imply that it was diffing a set
of commits (so even "diff-commit" would not be right, because that again
sounds like endpoints).

Sure.  This should't be a submode "--diff" of "git branch" just like
it shouldn't be a submode of "git commit" only because it is about
comparing two sets of commits.  "diff" is about comparing two
endpoints, and not about comparing two sets.  "log" is the closest
thing, if we really want to coerce it into an existing set of
commands, as it is about a set of commits, but it does not do
multiple sets, let alone comparing them.

"branch-diff" was just a good as "diff-history", except that both of
them may irritate command line completion users.  I do not think I
care too much about which exact command name it gets, but I think it
is a bad idea to tacked it to an existing command as a submode that
does unrelated thing to what the main command does.  So from that
point of view, "branch-diff" and "diff-history" are equally good
being a distinct command, and equally bad sharing prefix with common
existing command.