add test

packages/mobx-react/__tests__/exp.test.tsx

@@ -0,0 +1,63 @@
+import React from "react"
+import { observer } from "../src"
+import { render, act } from "@testing-library/react"
+
+/**
+ *  some test suite is too tedious
+ */
+
+afterEach(() => {
+    jest.useRealTimers()
+})
+
+// let consoleWarnMock: jest.SpyInstance | undefined
+// afterEach(() => {
+//     consoleWarnMock?.mockRestore()
+// })
+
+test("TODO", async () => {
+    let renderCount = 0
+    const Child = observer(function Child({ children }) {
+        renderCount++
+        // Accesses Parent's this.props
+        return children()
+    })
+
+    @observer
+    class Parent extends React.Component<any> {
+        // intentionally stable, so test breaks when you disable observable props (comment line 239 in observerClass)
+        renderCallback = () => {
+            return this.props.x
+        }
+        render() {
+            // Access observable props as part of child
+            return <Child>{this.renderCallback}</Child>
+        }
+    }
+
+    function Root() {
+        const [x, setX] = React.useState(0)
+        // Send new props to Parent
+        return (
+            <div onClick={() => setX(x => x + 1)}>
+                <Parent x={x} />
+            </div>
+        )
+    }
+
+    const app = <Root />
+
+    const { unmount, container } = render(app)
+
+    expect(container).toHaveTextContent("0")
+    expect(renderCount).toBe(1)
+
+    await new Promise(resolve => setTimeout(() => resolve(null), 1000))
+    act(() => {
+        console.log("changing state")
+        container.querySelector("div")?.click()
+    })
+    expect(container).toHaveTextContent("1")
+    expect(renderCount).toBe(2)
+    unmount()
+})