[RFC PATCH 09/13] commit-reach: test can_all_from_reach

[Derrick Stolee <dstolee@microsoft.com>]

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
---
 commit-reach.c        | 52 +++++++++++++++++++++++++++++++++++++++----
 commit-reach.h        |  4 +++-
 t/helper/test-reach.c |  7 ++++--
 t/t6600-test-reach.sh | 51 +++++++++++++++++++++++++++++++++++++++---
 upload-pack.c         |  2 +-
 5 files changed, 105 insertions(+), 11 deletions(-)

diff --git a/commit-reach.c b/commit-reach.c
index 44c09669ec..992ad5cdc7 100644
--- a/commit-reach.c
+++ b/commit-reach.c
@@ -562,14 +562,14 @@ static int reachable(struct commit *from, int with_flag, int assign_flag, time_t
 	return (from->object.flags & assign_flag);
 }
 
-int can_all_from_reach_with_flag(struct object_array from,
+int can_all_from_reach_with_flag(struct object_array *from,
 				 int with_flag, int assign_flag,
 				 time_t min_commit_date)
 {
 	int i;
 
-	for (i = 0; i < from.nr; i++) {
-		struct object *from_one = from.objects[i].item;
+	for (i = 0; i < from->nr; i++) {
+		struct object *from_one = from->objects[i].item;
 
 		if (from_one->flags & assign_flag)
 			continue;
@@ -580,7 +580,7 @@ int can_all_from_reach_with_flag(struct object_array from,
 			 * leave a note to ourselves not to worry about
 			 * this object anymore.
 			 */
-			from.objects[i].item->flags |= assign_flag;
+			from->objects[i].item->flags |= assign_flag;
 			continue;
 		}
 		if (!reachable((struct commit *)from_one, with_flag,
@@ -589,3 +589,47 @@ int can_all_from_reach_with_flag(struct object_array from,
 	}
 	return 1;
 }
+
+int can_all_from_reach(struct commit_list *from, struct commit_list *to)
+{
+	struct object_array from_objs = OBJECT_ARRAY_INIT;
+	time_t min_commit_date = from->item->date;
+	struct commit_list *from_iter = from;
+	struct commit_list *to_iter = to;
+	int result;
+
+	while (from_iter) {
+		add_object_array(&from_iter->item->object, NULL, &from_objs);
+
+		if (from_iter->item->date < min_commit_date)
+			min_commit_date = from_iter->item->date;
+
+		from_iter = from_iter->next;
+	}
+
+	while (to_iter) {
+		if (to_iter->item->date < min_commit_date)
+			min_commit_date = to_iter->item->date;
+
+		to_iter->item->object.flags |= PARENT2;
+
+		to_iter = to_iter->next;
+	}
+
+	result = can_all_from_reach_with_flag(&from_objs, PARENT2, PARENT1,
+					      min_commit_date);
+
+	while (from) {
+		clear_commit_marks(from->item, PARENT1);
+		from = from->next;
+	}
+
+	while (to) {
+		clear_commit_marks(to->item, PARENT2);
+		to = to->next;
+	}
+
+	object_array_clear(&from_objs);
+
+	return result;
+}
diff --git a/commit-reach.h b/commit-reach.h
index c3da8488eb..8ab06af2eb 100644
--- a/commit-reach.h
+++ b/commit-reach.h
@@ -27,7 +27,9 @@ int commit_contains(struct ref_filter *filter, struct commit *commit,
  * the 'with_flag' bit on? Mark the commits in 'from' that can reach
  * such commits with 'assign_flag'.
  */
-int can_all_from_reach_with_flag(struct object_array from, int with_flag,
+int can_all_from_reach_with_flag(struct object_array *from, int with_flag,
 				 int assign_flag, time_t min_commit_date);
 
+int can_all_from_reach(struct commit_list *from, struct commit_list *to);
+
 #endif
diff --git a/t/helper/test-reach.c b/t/helper/test-reach.c
index d57660af45..88639a2945 100644
--- a/t/helper/test-reach.c
+++ b/t/helper/test-reach.c
@@ -15,9 +15,9 @@ int cmd__reach(int ac, const char **av)
 	struct strbuf buf = STRBUF_INIT;
 
 	setup_git_directory();
-	get_git_config(default_git_config, 0);
+	git_config(git_default_config, NULL);
 
-	if (argc < 2)
+	if (ac < 2)
 		exit(1);
 
 	/* load input data */
@@ -117,6 +117,9 @@ int cmd__reach(int ac, const char **av)
 			printf("%s\n", oid_to_hex(&list->item->object.oid));
 			list = list->next;
 		}
+	} else if (!strcmp(av[1], "can_all_from_reach")) {
+		int result = can_all_from_reach(list_X, list_Y);
+		printf("%s(X,Y):%d\n", av[1], result);
 	}
 
 	exit(0);
diff --git a/t/t6600-test-reach.sh b/t/t6600-test-reach.sh
index 0f60db9c60..ef25e70174 100755
--- a/t/t6600-test-reach.sh
+++ b/t/t6600-test-reach.sh
@@ -64,7 +64,7 @@ test_expect_success 'ref_newer:miss' '
 	cat >expect <<- EOF &&
 	ref_newer:0
 	EOF
-	test_reach_two_modes "ref_newer"
+	test_reach_two_modes ref_newer
 '
 
 test_expect_success 'ref_newer:miss' '
@@ -75,7 +75,7 @@ test_expect_success 'ref_newer:miss' '
 	cat >expect <<- EOF &&
 	ref_newer:1
 	EOF
-	test_reach_two_modes "ref_newer"
+	test_reach_two_modes ref_newer
 '
 
 test_expect_success 'reduce_heads' '
@@ -101,7 +101,52 @@ test_expect_success 'reduce_heads' '
 	git rev-parse commit-1-10 >>expect &&
 	printf "reduce_heads(Y):\n" >>expect &&
 	git rev-parse commit-10-10 >>expect &&
-	test_reach_two_modes "reduce_heads"
+	test_reach_two_modes reduce_heads
+'
+
+test_expect_success 'can_all_from_reach:hit' '
+	cat >input <<- EOF &&
+	X:commit-2-10
+	X:commit-3-9
+	X:commit-4-8
+	X:commit-5-7
+	X:commit-6-6
+	X:commit-7-5
+	X:commit-8-4
+	X:commit-9-3
+	Y:commit-1-9
+	Y:commit-2-8
+	Y:commit-3-7
+	Y:commit-4-6
+	Y:commit-5-5
+	Y:commit-6-4
+	Y:commit-7-3
+	Y:commit-8-1
+	EOF
+	printf "can_all_from_reach(X,Y):1\n" >expect &&
+	test_reach_two_modes can_all_from_reach
+'
+
+test_expect_success 'can_all_from_reach:miss' '
+	cat >input <<- EOF &&
+	X:commit-2-10
+	X:commit-3-9
+	X:commit-4-8
+	X:commit-5-7
+	X:commit-6-6
+	X:commit-7-5
+	X:commit-8-4
+	X:commit-9-3
+	Y:commit-1-9
+	Y:commit-2-8
+	Y:commit-3-7
+	Y:commit-4-6
+	Y:commit-5-5
+	Y:commit-6-4
+	Y:commit-8-5
+	EOF
+	printf "can_all_from_reach(X,Y):0\n" >expect &&
+	test_reach_two_modes can_all_from_reach
 '
 
 test_done
diff --git a/upload-pack.c b/upload-pack.c
index 7c58cb8f5e..e59fbca257 100644
--- a/upload-pack.c
+++ b/upload-pack.c
@@ -339,7 +339,7 @@ static int ok_to_give_up(void)
 	if (!have_obj.nr)
 		return 0;
 
-	return can_all_from_reach_with_flag(want_obj, THEY_HAVE,
+	return can_all_from_reach_with_flag(&want_obj, THEY_HAVE,
 					    COMMON_KNOWN, oldest_have);
 }
 
-- 
2.18.0.118.gd4f65b8d14