mktree --missing: allow missing objects

We need to allow input lines that point at objects that we do not
have when dealing with submodule entries anyway.  This adds an explicit
option to allow missing objects of other types, to be consistent with
the use of --info-only option to the update-index command and --missing-ok
option to the write-tree command.

Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin-mktree.c

@@ -67,7 +67,7 @@ static const char *mktree_usage[] = {
 	NULL
 };
 
-static void mktree_line(char *buf, size_t len, int line_termination)
+static void mktree_line(char *buf, size_t len, int line_termination, int allow_missing)
 {
 	char *ptr, *ntr;
 	unsigned mode;
@@ -91,10 +91,13 @@ static void mktree_line(char *buf, size_t len, int line_termination)
 		die("input format error: %s", buf);
 
 	/* It is perfectly normal if we do not have a commit from a submodule */
-	if (!S_ISGITLINK(mode))
+	if (S_ISGITLINK(mode))
+		allow_missing = 1;
+
+	if (!allow_missing)
 		type = sha1_object_info(sha1, NULL);
 	else
-		type = OBJ_COMMIT;
+		type = object_type(mode);
 
 	if (type < 0)
 		die("object %s unavailable", sha1_to_hex(sha1));
@@ -118,15 +121,17 @@ int cmd_mktree(int ac, const char **av, const char *prefix)
 	struct strbuf sb = STRBUF_INIT;
 	unsigned char sha1[20];
 	int line_termination = '\n';
+	int allow_missing = 0;
 	const struct option option[] = {
 		OPT_SET_INT('z', NULL, &line_termination, "input is NUL terminated", '\0'),
+		OPT_SET_INT( 0 , "missing", &allow_missing, "allow missing objects", 1),
 		OPT_END()
 	};
 
 	ac = parse_options(ac, av, option, mktree_usage, 0);
 
 	while (strbuf_getline(&sb, stdin, line_termination) != EOF)
-		mktree_line(sb.buf, sb.len, line_termination);
+		mktree_line(sb.buf, sb.len, line_termination, allow_missing);
 
 	strbuf_release(&sb);
 

t/t1010-mktree.sh

@@ -10,6 +10,11 @@ test_expect_success setup '
 		mkdir "$d" && echo "$d/one" >"$d/one" &&
 		git add "$d"
 	done &&
+	echo zero >one &&
+	git update-index --add --info-only one &&
+	git write-tree --missing-ok >tree.missing &&
+	git ls-tree $(cat tree.missing) >top.missing &&
+	git ls-tree -r $(cat tree.missing) >all.missing &&
 	echo one >one &&
 	git add one &&
 	git write-tree >tree &&
@@ -48,6 +53,11 @@ test_expect_success 'ls-tree output in wrong order given to mktree (2)' '
 	test_cmp tree.withsub actual
 '
 
+test_expect_success 'allow missing object with --missing' '
+	git mktree --missing <top.missing >actual &&
+	test_cmp tree.missing actual
+'
+
 test_expect_failure 'mktree reads ls-tree -r output (1)' '
 	git mktree <all >actual &&
 	test_cmp tree actual