From 8521f9d3f63d26bde99b747f0cb14d0ac5ba5971 Mon Sep 17 00:00:00 2001
From: Evan You <yyx990803@gmail.com>
Date: Fri, 19 Aug 2022 12:22:51 +0800
Subject: [PATCH] fix(types): fix missing error for accessing undefined
 instance properties

fix #12718
---
 types/test/v3/define-component-test.tsx | 62 +++++++++++++++++++++++--
 types/v3-define-component.d.ts          | 10 ++--
 2 files changed, 64 insertions(+), 8 deletions(-)

diff --git a/types/test/v3/define-component-test.tsx b/types/test/v3/define-component-test.tsx
index 481a2d11ac7..7e6d1968ca3 100644
--- a/types/test/v3/define-component-test.tsx
+++ b/types/test/v3/define-component-test.tsx
@@ -1166,6 +1166,62 @@ defineComponent({
   }
 })
 
-// #12742 allow attaching custom properties (consistent with v3)
-const Foo = defineComponent({})
-Foo.foobar = 123
+describe('constructor attach custom properties', () => {
+  // #12742 allow attaching custom properties (consistent with v3)
+  const Foo = defineComponent({})
+  Foo.foobar = 123
+})
+
+describe('constructor instance type', () => {
+  const Comp = defineComponent({
+    data() {
+      return {
+        a: 1
+      }
+    },
+
+    computed: {
+      ac() {
+        return 1
+      }
+    },
+
+    methods: {
+      callA(b: number) {
+        return b
+      }
+    },
+
+    setup() {
+      return {
+        sa: '1'
+      }
+    }
+  })
+
+  const comp = new Comp()
+
+  expectType<number>(comp.a)
+  expectType<number>(comp.ac)
+  expectType<string>(comp.sa)
+  expectType<(b: number) => number>(comp.callA)
+})
+
+describe('should report non-existent properties in instance', () => {
+  const Foo = defineComponent({})
+  const instance = new Foo()
+  // @ts-expect-error
+  instance.foo
+
+  const Foo2 = defineComponent({
+    data() {
+      return {}
+    },
+    methods: {
+      example() {}
+    }
+  })
+  const instance2 = new Foo2()
+  // @ts-expect-error
+  instance2.foo
+})
diff --git a/types/v3-define-component.d.ts b/types/v3-define-component.d.ts
index 69f65a2ec35..03ef52d1856 100644
--- a/types/v3-define-component.d.ts
+++ b/types/v3-define-component.d.ts
@@ -72,7 +72,7 @@ export type DefineComponent<
  */
 export function defineComponent<
   RawBindings,
-  D = Data,
+  D = {},
   C extends ComputedOptions = {},
   M extends MethodOptions = {},
   Mixin extends ComponentOptionsMixin = ComponentOptionsMixin,
@@ -101,8 +101,8 @@ export function defineComponent<
  */
 export function defineComponent<
   PropNames extends string,
-  RawBindings = Data,
-  D = Data,
+  RawBindings = {},
+  D = {},
   C extends ComputedOptions = {},
   M extends MethodOptions = {},
   Mixin extends ComponentOptionsMixin = ComponentOptionsMixin,
@@ -140,8 +140,8 @@ export function defineComponent<
  */
 export function defineComponent<
   Props,
-  RawBindings = Data,
-  D = Data,
+  RawBindings = {},
+  D = {},
   C extends ComputedOptions = {},
   M extends MethodOptions = {},
   Mixin extends ComponentOptionsMixin = ComponentOptionsMixin,