diff --git a/src/test/resources/PatternRestrictionInTypedef.yang b/src/test/resources/PatternRestrictionInTypedef.yang
new file mode 100644
index 0000000..7875504
--- /dev/null
+++ b/src/test/resources/PatternRestrictionInTypedef.yang
@@ -0,0 +1,13 @@
+module Test {
+    yang-version 1;
+    namespace http://huawei.com;
+    prefix Ant;
+    leaf invalid-interval {
+        type hello;
+    }
+    typedef hello {
+        type string {
+            pattern "[a-zA-Z]";
+        }
+    }
+}