Re: [PATCH] grep --no-index: allow use of "git grep" outside a git repository

On Sun, Jan 17, 2010 at 08:02:25PM -0800, Junio C Hamano wrote:

Subject: "log --author=me --grep=it" should find intersection, not union

Historically, any grep filter in "git log" family of commands were taken
as restricting to commits with any of the words in the commit log message.
However, the user almost always want to find commits "done by this person
on that topic".  With "--all-match" option, a series of grep patterns can
be turned into a requirement that all of them must produce a match, but
that makes it impossible to ask for "done by me, on either this or that"
with:

	log --author=me --grep=this --grep=that

because it will require both "this" and "that" to appear.

Change the "header" parser of grep library to treat the headers specially.
When parsing the above, behave as if it was specified like this on the
command line:

	--all-match --author=me '(' --grep=this --grep=that ')'

Even though the "log" command line parser doesn't give direct access to
the extended grep syntax to group terms with parentheses, this change will
cover the majority of the case the users would want.

Hmm. I like the new behavior. The implementation feels a little
hack-ish, like we should really be supporting full-on:

  git log --author=me --and --grep=foo

That gets a little weird, though. We already have "--not" for ref
limiting, so clearly there is some conflict over exactly what logical
operators would be operating on. I guess we could use context to see
that the adjacent arguments were grep-related.

So perhaps, as you say, this is enough as it covers the usual case.

-Peff