Add '--bisect' revision machinery argument

I personally use "git bisect visualize" all the time when I bisect, but it
turns out that that is not a very flexible model. Sometimes I want to do
bisection based on all commits (no pathname limiting), but then visualize
the current bisection tree with just a few pathnames because I _suspect_
those pathnames are involved in the problem but am not totally sure about
them.

And at other times, I want to use other revision parsing logic, none of
which is available with "git bisect visualize".

So this adds "--bisect" as a revision parsing argument, and as a result it
just works with all the normal logging tools. So now I can just do

	gitk --bisect --simplify-by-decoration filename-here

etc.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 11 insertions, 0 deletions

diff --git a/builtin-rev-parse.c b/builtin-rev-parse.c
index 45bead6545..9526aafc6c 100644
--- a/builtin-rev-parse.c
+++ b/builtin-rev-parse.c
@@ -180,6 +180,12 @@ static int show_reference(const char *refname, const unsigned char *sha1, int fl
 	return 0;
 }
 
+static int anti_reference(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
+{
+	show_rev(REVERSED, sha1, refname);
+	return 0;
+}
+
 static void show_datestring(const char *flag, const char *datestr)
 {
 	static char buffer[100];
@@ -548,6 +554,11 @@ int cmd_rev_parse(int argc, const char **argv, const char *prefix)
 				for_each_ref(show_reference, NULL);
 				continue;
 			}
+			if (!strcmp(arg, "--bisect")) {
+				for_each_ref_in("refs/bisect/bad", show_reference, NULL);
+				for_each_ref_in("refs/bisect/good", anti_reference, NULL);
+				continue;
+			}
 			if (!strcmp(arg, "--branches")) {
 				for_each_branch_ref(show_reference, NULL);
 				continue;