Merge branch 'jk/pack-bitmap'

* jk/pack-bitmap:
  pack-objects: do not reuse packfiles without --delta-base-offset
  add `ignore_missing_links` mode to revwalk

builtin/pack-objects.c

@@ -2439,12 +2439,23 @@ static void loosen_unused_packed_objects(struct rev_info *revs)
 	}
 }
 
+/*
+ * This tracks any options which a reader of the pack might
+ * not understand, and which would therefore prevent blind reuse
+ * of what we have on disk.
+ */
+static int pack_options_allow_reuse(void)
+{
+	return allow_ofs_delta;
+}
+
 static int get_object_list_from_bitmap(struct rev_info *revs)
 {
 	if (prepare_bitmap_walk(revs) < 0)
 		return -1;
 
-	if (!reuse_partial_packfile_from_bitmap(
+	if (pack_options_allow_reuse() &&
+	    !reuse_partial_packfile_from_bitmap(
 			&reuse_packfile,
 			&reuse_packfile_objects,
 			&reuse_packfile_offset)) {

list-objects.c

@@ -81,8 +81,11 @@ static void process_tree(struct rev_info *revs,
 		die("bad tree object");
 	if (obj->flags & (UNINTERESTING | SEEN))
 		return;
-	if (parse_tree(tree) < 0)
+	if (parse_tree(tree) < 0) {
+		if (revs->ignore_missing_links)
+			return;
 		die("bad tree object %s", sha1_to_hex(obj->sha1));
+	}
 	obj->flags |= SEEN;
 	show(obj, path, name, cb_data);
 	me.up = path;

pack-bitmap.c

@@ -727,8 +727,10 @@ int prepare_bitmap_walk(struct rev_info *revs)
 	revs->pending.objects = NULL;
 
 	if (haves) {
+		revs->ignore_missing_links = 1;
 		haves_bitmap = find_objects(revs, haves, NULL);
 		reset_revision_walk();
+		revs->ignore_missing_links = 0;
 
 		if (haves_bitmap == NULL)
 			die("BUG: failed to perform bitmap walk");

revision.c

@@ -2960,10 +2960,12 @@ static struct commit *get_revision_1(struct rev_info *revs)
 			if (revs->max_age != -1 &&
 			    (commit->date < revs->max_age))
 				continue;
-			if (add_parents_to_list(revs, commit, &revs->commits, NULL) < 0)
+			if (add_parents_to_list(revs, commit, &revs->commits, NULL) < 0) {
+				if (!revs->ignore_missing_links)
 					die("Failed to traverse parents of commit %s",
 						sha1_to_hex(commit->object.sha1));
 			}
+		}
 
 		switch (simplify_commit(revs, commit)) {
 		case commit_ignore:

revision.h

@@ -75,7 +75,8 @@ struct rev_info {
 	enum rev_sort_order sort_order;
 
 	unsigned int	early_output:1,
-			ignore_missing:1;
+			ignore_missing:1,
+			ignore_missing_links:1;
 
 	/* Traversal flags */
 	unsigned int	dense:1,

t/t5310-pack-bitmaps.sh

@@ -3,6 +3,10 @@
 test_description='exercise basic bitmap functionality'
 . ./test-lib.sh
 
+objpath () {
+	echo ".git/objects/$(echo "$1" | sed -e 's|\(..\)|\1/|')"
+}
+
 test_expect_success 'setup repo with moderate-sized history' '
 	for i in $(test_seq 1 10); do
 		test_commit $i
@@ -115,6 +119,33 @@ test_expect_success 'fetch (full bitmap)' '
 	test_cmp expect actual
 '
 
+test_expect_success 'create objects for missing-HAVE tests' '
+	blob=$(echo "missing have" | git hash-object -w --stdin) &&
+	tree=$(printf "100644 blob $blob\tfile\n" | git mktree) &&
+	parent=$(echo parent | git commit-tree $tree) &&
+	commit=$(echo commit | git commit-tree $tree -p $parent) &&
+	cat >revs <<-EOF
+	HEAD
+	^HEAD^
+	^$commit
+	EOF
+'
+
+test_expect_success 'pack with missing blob' '
+	rm $(objpath $blob) &&
+	git pack-objects --stdout --revs <revs >/dev/null
+'
+
+test_expect_success 'pack with missing tree' '
+	rm $(objpath $tree) &&
+	git pack-objects --stdout --revs <revs >/dev/null
+'
+
+test_expect_success 'pack with missing parent' '
+	rm $(objpath $parent) &&
+	git pack-objects --stdout --revs <revs >/dev/null
+'
+
 test_lazy_prereq JGIT '
 	type jgit
 '