push, fetch: error out for submodule entries not pointing to commits

stefanbeller · gitster · commit 3c96aa972323 · 2017-09-14T15:05:51.000+09:00
The check_has_commit helper uses resolves a submodule entry to a
commit, when validating its existence. As a side effect this means
tolerates a submodule entry pointing to a tag, which is not a valid
submodule entry that git commands would know how to cope with.

Tighten the check to require an actual commit, not a tag pointing to a
commit.

Also improve the error handling when a submodule entry points to
non-commit (e.g., a blob) to error out instead of warning and
pretending the pointed to object doesn't exist.

Signed-off-by: Stefan Beller &lt;sbeller@google.com&gt;
Signed-off-by: Jonathan Nieder &lt;jrnieder@gmail.com&gt;
Signed-off-by: Junio C Hamano &lt;gitster@pobox.com&gt;
diff --git a/submodule.c b/submodule.c
@@ -767,19 +767,36 @@ static int append_oid_to_argv(const struct object_id *oid, void *data)
 	return 0;
 }
 
+struct has_commit_data {
+	int result;
+	const char *path;
+};
+
 static int check_has_commit(const struct object_id *oid, void *data)
 {
-	int *has_commit = data;
+	struct has_commit_data *cb = data;
 
-	if (!lookup_commit_reference(oid))
-		*has_commit = 0;
+	enum object_type type = sha1_object_info(oid->hash, NULL);
 
-	return 0;
+	switch (type) {
+	case OBJ_COMMIT:
+		return 0;
+	case OBJ_BAD:
+		/*
+		 * Object is missing or invalid. If invalid, an error message
+		 * has already been printed.
+		 */
+		cb->result = 0;
+		return 0;
+	default:
+		die(_("submodule entry '%s' (%s) is a %s, not a commit"),
+		    cb->path, oid_to_hex(oid), typename(type));
+	}
 }
 
 static int submodule_has_commits(const char *path, struct oid_array *commits)
 {
-	int has_commit = 1;
+	struct has_commit_data has_commit = { 1, path };
 
 	/*
 	 * Perform a cheap, but incorrect check for the existence of 'commits'.
@@ -795,7 +812,7 @@ static int submodule_has_commits(const char *path, struct oid_array *commits)
 
 	oid_array_for_each_unique(commits, check_has_commit, &has_commit);
 
-	if (has_commit) {
+	if (has_commit.result) {
 		/*
 		 * Even if the submodule is checked out and the commit is
 		 * present, make sure it exists in the submodule's object store
@@ -814,12 +831,12 @@ static int submodule_has_commits(const char *path, struct oid_array *commits)
 		cp.dir = path;
 
 		if (capture_command(&cp, &out, GIT_MAX_HEXSZ + 1) || out.len)
-			has_commit = 0;
+			has_commit.result = 0;
 
 		strbuf_release(&out);
 	}
 
-	return has_commit;
+	return has_commit.result;
 }
 
 static int submodule_needs_pushing(const char *path, struct oid_array *commits)
diff --git a/t/t5531-deep-submodule-push.sh b/t/t5531-deep-submodule-push.sh
@@ -298,6 +298,16 @@ test_expect_success 'push succeeds if submodule commit disabling recursion from
 	)
 '
 
+test_expect_success 'submodule entry pointing at a tag is error' '
+	git -C work/gar/bage tag -a test1 -m "tag" &&
+	tag=$(git -C work/gar/bage rev-parse test1^{tag}) &&
+	git -C work update-index --cacheinfo 160000 "$tag" gar/bage &&
+	git -C work commit -m "bad commit" &&
+	test_when_finished "git -C work reset --hard HEAD^" &&
+	test_must_fail git -C work push --recurse-submodules=on-demand ../pub.git master 2>err &&
+	test_i18ngrep "is a tag, not a commit" err
+'
+
 test_expect_success 'push fails if recurse submodules option passed as yes' '
 	(
 		cd work/gar/bage &&

Original file line number	Diff line number	Diff line change
`@@ -298,6 +298,16 @@ test_expect_success 'push succeeds if submodule commit disabling recursion from`
`298`	`298`	`)`
`299`	`299`	`'`
`300`	`300`
	`301`	`+test_expect_success 'submodule entry pointing at a tag is error' '`
	`302`	`+ git -C work/gar/bage tag -a test1 -m "tag" &&`
	`303`	`+ tag=$(git -C work/gar/bage rev-parse test1^{tag}) &&`
	`304`	`+ git -C work update-index --cacheinfo 160000 "$tag" gar/bage &&`
	`305`	`+ git -C work commit -m "bad commit" &&`
	`306`	`+ test_when_finished "git -C work reset --hard HEAD^" &&`
	`307`	`+ test_must_fail git -C work push --recurse-submodules=on-demand ../pub.git master 2>err &&`
	`308`	`+ test_i18ngrep "is a tag, not a commit" err`
	`309`	`+'`
	`310`	`+`
`301`	`311`	`test_expect_success 'push fails if recurse submodules option passed as yes' '`
`302`	`312`	`(`
`303`	`313`	`cd work/gar/bage &&`