revision: introduce prepare_revision_walk_extended()rs/revision-keep-pending

prepare_revision_walk() allows callers to take ownership of the array of
pending objects by setting the rev_info flag "leak_pending" and copying
the object_array "pending".  They use it to clear commit marks after
setup is done.  This interface is brittle enough that it requires
extensive comments.

Provide an easier way by adding a function that can hand over the array
to a caller-supplied output parameter and converting all users of the
flag "leak_pending" to call prepare_revision_walk_extended() instead.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 5 insertions, 12 deletions

diff --git a/bisect.c b/bisect.c
index 3756f127b0..3539cc9c61 100644
--- a/bisect.c
+++ b/bisect.c
@@ -636,9 +636,10 @@ static void bisect_rev_setup(struct rev_info *revs, const char *prefix,
 	/* XXX leak rev_argv, as "revs" may still be pointing to it */
 }
 
-static void bisect_common(struct rev_info *revs)
+static void bisect_common(struct rev_info *revs,
+			  struct object_array *old_pending_ptr)
 {
-	if (prepare_revision_walk(revs))
+	if (prepare_revision_walk_extended(revs, old_pending_ptr))
 		die("revision walk setup failed");
 	if (revs->tree_objects)
 		mark_edges_uninteresting(revs, NULL);
@@ -819,15 +820,7 @@ static int check_ancestors(const char *prefix)
 	bisect_rev_setup(&revs, prefix, "^%s", "%s", 0);
 
 	/* Save pending objects, so they can be cleaned up later. */
-	pending_copy = revs.pending;
-	revs.leak_pending = 1;
-
-	/*
-	 * bisect_common calls prepare_revision_walk right away, which
-	 * (together with .leak_pending = 1) makes us the sole owner of
-	 * the list of pending objects.
-	 */
-	bisect_common(&revs);
+	bisect_common(&revs, &pending_copy);
 	res = (revs.commits != NULL);
 
 	/* Clean up objects used, as they will be reused. */
@@ -958,7 +951,7 @@ int bisect_next_all(const char *prefix, int no_checkout)
 	bisect_rev_setup(&revs, prefix, "%s", "^%s", 1);
 	revs.limited = 1;
 
-	bisect_common(&revs);
+	bisect_common(&revs, NULL);
 
 	find_bisection(&revs.commits, &reaches, &all, !!skipped_revs.nr);
 	revs.commits = managed_skipped(revs.commits, &tried);