tag: Refuse to use HEAD as a tagname

csware · csware · commit 3dc766a875fe · 2025-04-07T21:18:20.000+02:00
Sync with vanilla Git, cf. git/git@bbd445d5efd415 Signed-off-by: Sven Strickroth <email@cs-ware.de>
diff --git a/src/libgit2/tag.c b/src/libgit2/tag.c
@@ -263,8 +263,10 @@ static bool tag_name_is_valid(const char *tag_name)
 	/*
 	 * Discourage tag name starting with dash,
 	 * https://github.com/git/git/commit/4f0accd638b8d2
+	 * and refuse to use HEAD as a tagname,
+	 * https://github.com/git/git/commit/bbd445d5efd415
 	 */
-	return tag_name[0] != '-';
+	return tag_name[0] != '-' && git__strcmp(tag_name, "HEAD");
 }
 
 static int git_tag_create__internal(
diff --git a/tests/libgit2/refs/tags/name.c b/tests/libgit2/refs/tags/name.c
@@ -11,7 +11,9 @@ void test_refs_tags_name__is_name_valid(void)
 {
 	cl_assert_equal_i(true, name_is_valid("sometag"));
 	cl_assert_equal_i(true, name_is_valid("test/sometag"));
+	cl_assert_equal_i(true, name_is_valid("test/HEAD"));
 
 	cl_assert_equal_i(false, name_is_valid(""));
 	cl_assert_equal_i(false, name_is_valid("-dash"));
+	cl_assert_equal_i(false, name_is_valid("HEAD"));
 }

Original file line number	Diff line number	Diff line change
`@@ -11,7 +11,9 @@ void test_refs_tags_name__is_name_valid(void)`
`11`	`11`	`{`
`12`	`12`	`cl_assert_equal_i(true, name_is_valid("sometag"));`
`13`	`13`	`cl_assert_equal_i(true, name_is_valid("test/sometag"));`
	`14`	`+ cl_assert_equal_i(true, name_is_valid("test/HEAD"));`
`14`	`15`
`15`	`16`	`cl_assert_equal_i(false, name_is_valid(""));`
`16`	`17`	`cl_assert_equal_i(false, name_is_valid("-dash"));`
	`18`	`+ cl_assert_equal_i(false, name_is_valid("HEAD"));`
`17`	`19`	`}`