diff --git a/test/component.test.ts b/test/component.test.ts
index 7317097..de6fa11 100644
--- a/test/component.test.ts
+++ b/test/component.test.ts
@@ -120,6 +120,17 @@ Component({
   },
 })
 
+expectError(
+  Component({
+    custom: 1,
+    methods: {
+      f() {
+        this.custom
+      },
+    },
+  }),
+)
+
 interface Config {
   a: number
 }
diff --git a/test/issue.test.ts b/test/issue.test.ts
index f218a77..0dfd294 100644
--- a/test/issue.test.ts
+++ b/test/issue.test.ts
@@ -464,7 +464,6 @@ import WX = WechatMiniprogram
   }
 
   Component({
-    _timer: '',
     properties: {
       bar: {
         type: Object,
@@ -483,7 +482,6 @@ import WX = WechatMiniprogram
       test() {
         expectType<Foo>(this.data.bar)
         expectType<Foo[]>(this.getData())
-        expectType<string>(this._timer)
       },
     }
   })