Split useRef tests into separate file

Author: Brian Vaughn

packages/react-reconciler/src/__tests__/ReactHooksWithNoopRenderer-test.internal.js

@@ -1417,7 +1417,7 @@ describe('ReactHooksWithNoopRenderer', () => {
       it('does not show a warning when a component updates a childs state from within passive unmount function', () => {
         function Parent() {
           Scheduler.unstable_yieldValue('Parent');
-          const updaterRef = React.useRef(null);
+          const updaterRef = useRef(null);
           React.useEffect(() => {
             Scheduler.unstable_yieldValue('Parent passive create');
             return () => {
@@ -2526,91 +2526,6 @@ describe('ReactHooksWithNoopRenderer', () => {
     });
   });
 
-  describe('useRef', () => {
-    it('creates a ref object initialized with the provided value', () => {
-      jest.useFakeTimers();
-
-      function useDebouncedCallback(callback, ms, inputs) {
-        const timeoutID = useRef(-1);
-        useEffect(() => {
-          return function unmount() {
-            clearTimeout(timeoutID.current);
-          };
-        }, []);
-        const debouncedCallback = useCallback(
-          (...args) => {
-            clearTimeout(timeoutID.current);
-            timeoutID.current = setTimeout(callback, ms, ...args);
-          },
-          [callback, ms],
-        );
-        return useCallback(debouncedCallback, inputs);
-      }
-
-      let ping;
-      function App() {
-        ping = useDebouncedCallback(
-          value => {
-            Scheduler.unstable_yieldValue('ping: ' + value);
-          },
-          100,
-          [],
-        );
-        return null;
-      }
-
-      act(() => {
-        ReactNoop.render(<App />);
-      });
-      expect(Scheduler).toHaveYielded([]);
-
-      ping(1);
-      ping(2);
-      ping(3);
-
-      expect(Scheduler).toHaveYielded([]);
-
-      jest.advanceTimersByTime(100);
-
-      expect(Scheduler).toHaveYielded(['ping: 3']);
-
-      ping(4);
-      jest.advanceTimersByTime(20);
-      ping(5);
-      ping(6);
-      jest.advanceTimersByTime(80);
-
-      expect(Scheduler).toHaveYielded([]);
-
-      jest.advanceTimersByTime(20);
-      expect(Scheduler).toHaveYielded(['ping: 6']);
-    });
-
-    it('should return the same ref during re-renders', () => {
-      function Counter() {
-        const ref = useRef('val');
-        const [count, setCount] = useState(0);
-        const [firstRef] = useState(ref);
-
-        if (firstRef !== ref) {
-          throw new Error('should never change');
-        }
-
-        if (count < 3) {
-          setCount(count + 1);
-        }
-
-        return <Text text={ref.current} />;
-      }
-
-      ReactNoop.render(<Counter />);
-      expect(Scheduler).toFlushAndYield(['val']);
-
-      ReactNoop.render(<Counter />);
-      expect(Scheduler).toFlushAndYield(['val']);
-    });
-  });
-
   describe('useImperativeHandle', () => {
     it('does not update when deps are the same', () => {
       const INCREMENT = 'INCREMENT';

packages/react-reconciler/src/__tests__/useRef-test.internal.js

@@ -0,0 +1,127 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @emails react-core
+ * @jest-environment node
+ */
+
+/* eslint-disable no-func-assign */
+
+'use strict';
+
+describe('useRef', () => {
+  let React;
+  let ReactNoop;
+  let Scheduler;
+  let act;
+  let useCallback;
+  let useEffect;
+  let useRef;
+  let useState;
+
+  beforeEach(() => {
+    React = require('react');
+    ReactNoop = require('react-noop-renderer');
+    Scheduler = require('scheduler');
+
+    const ReactFeatureFlags = require('shared/ReactFeatureFlags');
+    ReactFeatureFlags.debugRenderPhaseSideEffectsForStrictMode = false;
+
+    act = ReactNoop.act;
+    useCallback = React.useCallback;
+    useEffect = React.useEffect;
+    useRef = React.useRef;
+    useState = React.useState;
+  });
+
+  function Text(props) {
+    Scheduler.unstable_yieldValue(props.text);
+    return <span prop={props.text} />;
+  }
+
+  it('creates a ref object initialized with the provided value', () => {
+    jest.useFakeTimers();
+
+    function useDebouncedCallback(callback, ms, inputs) {
+      const timeoutID = useRef(-1);
+      useEffect(() => {
+        return function unmount() {
+          clearTimeout(timeoutID.current);
+        };
+      }, []);
+      const debouncedCallback = useCallback(
+        (...args) => {
+          clearTimeout(timeoutID.current);
+          timeoutID.current = setTimeout(callback, ms, ...args);
+        },
+        [callback, ms],
+      );
+      return useCallback(debouncedCallback, inputs);
+    }
+
+    let ping;
+    function App() {
+      ping = useDebouncedCallback(
+        value => {
+          Scheduler.unstable_yieldValue('ping: ' + value);
+        },
+        100,
+        [],
+      );
+      return null;
+    }
+
+    act(() => {
+      ReactNoop.render(<App />);
+    });
+    expect(Scheduler).toHaveYielded([]);
+
+    ping(1);
+    ping(2);
+    ping(3);
+
+    expect(Scheduler).toHaveYielded([]);
+
+    jest.advanceTimersByTime(100);
+
+    expect(Scheduler).toHaveYielded(['ping: 3']);
+
+    ping(4);
+    jest.advanceTimersByTime(20);
+    ping(5);
+    ping(6);
+    jest.advanceTimersByTime(80);
+
+    expect(Scheduler).toHaveYielded([]);
+
+    jest.advanceTimersByTime(20);
+    expect(Scheduler).toHaveYielded(['ping: 6']);
+  });
+
+  it('should return the same ref during re-renders', () => {
+    function Counter() {
+      const ref = useRef('val');
+      const [count, setCount] = useState(0);
+      const [firstRef] = useState(ref);
+
+      if (firstRef !== ref) {
+        throw new Error('should never change');
+      }
+
+      if (count < 3) {
+        setCount(count + 1);
+      }
+
+      return <Text text={ref.current} />;
+    }
+
+    ReactNoop.render(<Counter />);
+    expect(Scheduler).toFlushAndYield(['val']);
+
+    ReactNoop.render(<Counter />);
+    expect(Scheduler).toFlushAndYield(['val']);
+  });
+});