fix(inject): should auto unwrap injected refs

fix #4196

packages/runtime-core/__tests__/apiOptions.spec.ts

@@ -9,7 +9,8 @@ import {
   renderToString,
   ref,
   defineComponent,
-  createApp
+  createApp,
+  computed
 } from '@vue/runtime-test'
 
 describe('api: options', () => {
@@ -426,6 +427,69 @@ describe('api: options', () => {
     expect(renderToString(h(Root))).toBe(`1111234522`)
   })
 
+  test('provide/inject refs', async () => {
+    const n = ref(0)
+    const np = computed(() => n.value + 1)
+    const Parent = defineComponent({
+      provide() {
+        return {
+          n,
+          np
+        }
+      },
+      render: () => h(Child)
+    })
+    const Child = defineComponent({
+      inject: ['n', 'np'],
+      render(this: any) {
+        return this.n + this.np
+      }
+    })
+    const app = createApp(Parent)
+    // TODO remove in 3.3
+    app.config.unwrapInjectedRef = true
+    const root = nodeOps.createElement('div')
+    app.mount(root)
+    expect(serializeInner(root)).toBe(`1`)
+
+    n.value++
+    await nextTick()
+    expect(serializeInner(root)).toBe(`3`)
+  })
+
+  // TODO remove in 3.3
+  test('provide/inject refs (compat)', async () => {
+    const n = ref(0)
+    const np = computed(() => n.value + 1)
+    const Parent = defineComponent({
+      provide() {
+        return {
+          n,
+          np
+        }
+      },
+      render: () => h(Child)
+    })
+    const Child = defineComponent({
+      inject: ['n', 'np'],
+      render(this: any) {
+        return this.n.value + this.np.value
+      }
+    })
+    const app = createApp(Parent)
+
+    const root = nodeOps.createElement('div')
+    app.mount(root)
+    expect(serializeInner(root)).toBe(`1`)
+
+    n.value++
+    await nextTick()
+    expect(serializeInner(root)).toBe(`3`)
+
+    expect(`injected property "n" is a ref`).toHaveBeenWarned()
+    expect(`injected property "np" is a ref`).toHaveBeenWarned()
+  })
+
   test('provide accessing data in extends', () => {
     const Base = defineComponent({
       data() {