[fix] Optimize ref merging

Close necolas#1746
Fix necolas#1665

src/exports/Picker/index.js

@@ -11,7 +11,7 @@
 import type { ViewProps } from '../View';
 
 import createElement from '../createElement';
-import setAndForwardRef from '../../modules/setAndForwardRef';
+import useMergeRefs from '../../modules/useMergeRefs';
 import usePlatformMethods from '../../hooks/usePlatformMethods';
 import PickerItem from './PickerItem';
 import StyleSheet, { type StyleObj } from '../StyleSheet';
@@ -47,12 +47,7 @@ const Picker = forwardRef<PickerProps, *>((props, forwardedRef) => {
   } = props;
 
   const hostRef = useRef(null);
-  const setRef = setAndForwardRef({
-    getForwardedRef: () => forwardedRef,
-    setLocalRef: hostNode => {
-      hostRef.current = hostNode;
-    }
-  });
+  const setRef = useMergeRefs(forwardedRef, hostRef);
 
   function handleChange(e: Object) {
     const { selectedIndex, value } = e.target;

src/exports/Pressable/index.js

@@ -15,7 +15,7 @@ import type { ViewProps } from '../View';
 
 import * as React from 'react';
 import { forwardRef, memo, useMemo, useState, useRef } from 'react';
-import setAndForwardRef from '../../modules/setAndForwardRef';
+import useMergeRefs from '../../modules/useMergeRefs';
 import usePressEvents from '../../hooks/usePressEvents';
 import View from '../View';
 
@@ -97,12 +97,7 @@ function Pressable(props: Props, forwardedRef): React.Node {
   const [pressed, setPressed] = useForceableState(testOnly_pressed === true);
 
   const hostRef = useRef(null);
-  const setRef = setAndForwardRef({
-    getForwardedRef: () => forwardedRef,
-    setLocalRef: hostNode => {
-      hostRef.current = hostNode;
-    }
-  });
+  const setRef = useMergeRefs(forwardedRef, hostRef);
 
   const pressConfig = useMemo(
     () => ({

src/exports/Text/index.js

@@ -15,8 +15,8 @@ import { forwardRef, useContext, useRef } from 'react';
 import createElement from '../createElement';
 import css from '../StyleSheet/css';
 import pick from '../../modules/pick';
-import setAndForwardRef from '../../modules/setAndForwardRef';
 import useElementLayout from '../../hooks/useElementLayout';
+import useMergeRefs from '../../modules/useMergeRefs';
 import usePlatformMethods from '../../hooks/usePlatformMethods';
 import useResponderEvents from '../../hooks/useResponderEvents';
 import StyleSheet from '../StyleSheet';
@@ -100,12 +100,7 @@ const Text = forwardRef<TextProps, *>((props, forwardedRef) => {
 
   const hasTextAncestor = useContext(TextAncestorContext);
   const hostRef = useRef(null);
-  const setRef = setAndForwardRef({
-    getForwardedRef: () => forwardedRef,
-    setLocalRef: hostNode => {
-      hostRef.current = hostNode;
-    }
-  });
+  const setRef = useMergeRefs(forwardedRef, hostRef);
 
   const classList = [
     classes.text,

src/exports/TextInput/__tests__/index-test.js

@@ -633,4 +633,18 @@ describe('components/TextInput', () => {
     const input = findInput(container);
     expect(input.value).toEqual(value);
   });
+
+  describe('imperative methods', () => {
+    test('node.clear()', () => {
+      const ref = React.createRef();
+      render(<TextInput ref={ref} />);
+      expect(typeof ref.current.clear).toBe('function');
+    });
+
+    test('node.isFocused()', () => {
+      const ref = React.createRef();
+      render(<TextInput ref={ref} />);
+      expect(typeof ref.current.isFocused).toBe('function');
+    });
+  });
 });

src/exports/TextInput/index.js

@@ -10,13 +10,13 @@
 
 import type { TextInputProps } from './types';
 
-import { forwardRef, useRef } from 'react';
+import { forwardRef, useCallback, useMemo, useRef } from 'react';
 import createElement from '../createElement';
 import css from '../StyleSheet/css';
 import pick from '../../modules/pick';
-import setAndForwardRef from '../../modules/setAndForwardRef';
 import useElementLayout from '../../hooks/useElementLayout';
 import useLayoutEffect from '../../hooks/useLayoutEffect';
+import useMergeRefs from '../../modules/useMergeRefs';
 import usePlatformMethods from '../../hooks/usePlatformMethods';
 import useResponderEvents from '../../hooks/useResponderEvents';
 import StyleSheet from '../StyleSheet';
@@ -186,11 +186,31 @@ const TextInput = forwardRef<TextInputProps, *>((props, forwardedRef) => {
     type = 'password';
   }
 
-  const hostRef = useRef(null);
   const dimensions = useRef({ height: null, width: null });
-  const setRef = setAndForwardRef({
-    getForwardedRef: () => forwardedRef,
-    setLocalRef: hostNode => {
+  const hostRef = useRef(null);
+
+  const handleContentSizeChange = useCallback(() => {
+    const node = hostRef.current;
+    if (multiline && onContentSizeChange && node != null) {
+      const newHeight = node.scrollHeight;
+      const newWidth = node.scrollWidth;
+      if (newHeight !== dimensions.current.height || newWidth !== dimensions.current.width) {
+        dimensions.current.height = newHeight;
+        dimensions.current.width = newWidth;
+        onContentSizeChange({
+          nativeEvent: {
+            contentSize: {
+              height: dimensions.current.height,
+              width: dimensions.current.width
+            }
+          }
+        });
+      }
+    }
+  }, [hostRef, multiline, onContentSizeChange]);
+
+  const imperativeRef = useMemo(
+    () => hostNode => {
       // TextInput needs to add more methods to the hostNode in addition to those
       // added by `usePlatformMethods`. This is temporarily until an API like
       // `TextInput.clear(hostRef)` is added to React Native.
@@ -203,13 +223,13 @@ const TextInput = forwardRef<TextInputProps, *>((props, forwardedRef) => {
         hostNode.isFocused = function() {
           return hostNode != null && TextInputState.currentlyFocusedField() === hostNode;
         };
-      }
-      hostRef.current = hostNode;
-      if (hostRef.current != null) {
         handleContentSizeChange();
       }
-    }
-  });
+    },
+    [handleContentSizeChange]
+  );
+
+  const setRef = useMergeRefs(forwardedRef, hostRef, imperativeRef);
 
   function handleBlur(e) {
     TextInputState._currentlyFocusedNode = null;
@@ -219,26 +239,6 @@ const TextInput = forwardRef<TextInputProps, *>((props, forwardedRef) => {
     }
   }
 
-  function handleContentSizeChange() {
-    const node = hostRef.current;
-    if (multiline && onContentSizeChange && node != null) {
-      const newHeight = node.scrollHeight;
-      const newWidth = node.scrollWidth;
-      if (newHeight !== dimensions.current.height || newWidth !== dimensions.current.width) {
-        dimensions.current.height = newHeight;
-        dimensions.current.width = newWidth;
-        onContentSizeChange({
-          nativeEvent: {
-            contentSize: {
-              height: dimensions.current.height,
-              width: dimensions.current.width
-            }
-          }
-        });
-      }
-    }
-  }
-
   function handleChange(e) {
     const text = e.target.value;
     e.nativeEvent.text = text;

src/exports/TouchableHighlight/index.js

@@ -16,8 +16,8 @@ import type { ViewProps } from '../View';
 
 import * as React from 'react';
 import { useCallback, useMemo, useState, useRef } from 'react';
+import useMergeRefs from '../../modules/useMergeRefs';
 import usePressEvents from '../../hooks/usePressEvents';
-import setAndForwardRef from '../../modules/setAndForwardRef';
 import StyleSheet from '../StyleSheet';
 import View from '../View';
 
@@ -93,12 +93,7 @@ function TouchableHighlight(props: Props, forwardedRef): React.Node {
   } = props;
 
   const hostRef = useRef(null);
-  const setRef = setAndForwardRef({
-    getForwardedRef: () => forwardedRef,
-    setLocalRef: hostNode => {
-      hostRef.current = hostNode;
-    }
-  });
+  const setRef = useMergeRefs(forwardedRef, hostRef);
 
   const [extraStyles, setExtraStyles] = useState(
     testOnly_pressed === true ? createExtraStyles(activeOpacity, underlayColor) : null

src/exports/TouchableOpacity/index.js

@@ -15,8 +15,8 @@ import type { ViewProps } from '../View';
 
 import * as React from 'react';
 import { useCallback, useMemo, useState, useRef } from 'react';
+import useMergeRefs from '../../modules/useMergeRefs';
 import usePressEvents from '../../hooks/usePressEvents';
-import setAndForwardRef from '../../modules/setAndForwardRef';
 import StyleSheet from '../StyleSheet';
 import View from '../View';
 
@@ -51,12 +51,7 @@ function TouchableOpacity(props: Props, forwardedRef): React.Node {
   } = props;
 
   const hostRef = useRef(null);
-  const setRef = setAndForwardRef({
-    getForwardedRef: () => forwardedRef,
-    setLocalRef: hostNode => {
-      hostRef.current = hostNode;
-    }
-  });
+  const setRef = useMergeRefs(forwardedRef, hostRef);
 
   const [duration, setDuration] = useState('0s');
   const [opacityOverride, setOpacityOverride] = useState(null);

src/exports/TouchableWithoutFeedback/__tests__/index-test.js

@@ -0,0 +1,26 @@
+import React from 'react';
+import { render } from '@testing-library/react';
+import TouchableWithoutFeedback from '../';
+import View from '../../View';
+
+describe('components/TouchableWithoutFeedback', () => {
+  test('forwards ref', () => {
+    const ref = jest.fn();
+    render(
+      <TouchableWithoutFeedback ref={ref}>
+        <View />
+      </TouchableWithoutFeedback>
+    );
+    expect(ref).toHaveBeenCalled();
+  });
+
+  test('forwards ref of child', () => {
+    const ref = jest.fn();
+    render(
+      <TouchableWithoutFeedback>
+        <View ref={ref} />
+      </TouchableWithoutFeedback>
+    );
+    expect(ref).toHaveBeenCalled();
+  });
+});

src/exports/TouchableWithoutFeedback/index.js

@@ -16,7 +16,7 @@ import type { ViewProps } from '../View';
 import * as React from 'react';
 import { useMemo, useRef } from 'react';
 import pick from '../../modules/pick';
-import setAndForwardRef from '../../modules/setAndForwardRef';
+import useMergeRefs from '../../modules/useMergeRefs';
 import usePressEvents from '../../hooks/usePressEvents';
 
 export type Props = $ReadOnly<{|
@@ -115,20 +115,7 @@ function TouchableWithoutFeedback(props: Props, forwardedRef): React.Node {
   supportedProps.accessible = accessible !== false;
   supportedProps.accessibilityState = { disabled, ...props.accessibilityState };
   supportedProps.focusable = focusable !== false && onPress !== undefined;
-  supportedProps.ref = setAndForwardRef({
-    getForwardedRef: () => forwardedRef,
-    setLocalRef: hostNode => {
-      const { ref } = element;
-      if (ref != null) {
-        if (typeof ref === 'function') {
-          ref(hostNode);
-        } else {
-          ref.current = hostNode;
-        }
-      }
-      hostRef.current = hostNode;
-    }
-  });
+  supportedProps.ref = useMergeRefs(forwardedRef, hostRef, element.ref);
 
   const elementProps = Object.assign(supportedProps, pressEventHandlers);
 

src/exports/View/index.js

@@ -15,8 +15,8 @@ import { forwardRef, useContext, useRef } from 'react';
 import createElement from '../createElement';
 import css from '../StyleSheet/css';
 import pick from '../../modules/pick';
-import setAndForwardRef from '../../modules/setAndForwardRef';
 import useElementLayout from '../../hooks/useElementLayout';
+import useMergeRefs from '../../modules/useMergeRefs';
 import usePlatformMethods from '../../hooks/usePlatformMethods';
 import useResponderEvents from '../../hooks/useResponderEvents';
 import StyleSheet from '../StyleSheet';
@@ -102,12 +102,7 @@ const View = forwardRef<ViewProps, *>((props, forwardedRef) => {
 
   const hasTextAncestor = useContext(TextAncestorContext);
   const hostRef = useRef(null);
-  const setRef = setAndForwardRef({
-    getForwardedRef: () => forwardedRef,
-    setLocalRef: hostNode => {
-      hostRef.current = hostNode;
-    }
-  });
+  const setRef = useMergeRefs(forwardedRef, hostRef);
 
   const classList = [classes.view];
   const style = StyleSheet.compose(

src/modules/mergeRefs/__tests__/index-test.js

@@ -0,0 +1,31 @@
+/**
+ * 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.
+ */
+
+import * as React from 'react';
+import mergeRefs from '..';
+import { render } from '@testing-library/react';
+
+describe('modules/mergeRefs', () => {
+  test('merges refs of different types', () => {
+    const ref = React.createRef(null);
+    let functionRefValue = null;
+    let hookRef;
+    function Component() {
+      const functionRef = x => {
+        functionRefValue = x;
+      };
+      hookRef = React.useRef(null);
+      return <div ref={mergeRefs(ref, hookRef, functionRef)} />;
+    }
+
+    render(<Component />);
+
+    expect(ref.current).not.toBe(null);
+    expect(hookRef.current).not.toBe(null);
+    expect(functionRefValue).not.toBe(null);
+  });
+});

src/modules/mergeRefs/index.js

@@ -0,0 +1,33 @@
+/**
+ * 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.
+ *
+ * @flow strict
+ */
+
+import * as React from 'react';
+
+export default function mergeRefs(...args: $ReadOnlyArray<React.ElementRef<any>>) {
+  return function forwardRef(node: HTMLElement | null) {
+    args.forEach((ref: React.ElementRef<any>) => {
+      if (ref == null) {
+        return;
+      }
+      if (typeof ref === 'function') {
+        ref(node);
+        return;
+      }
+      if (typeof ref === 'object') {
+        ref.current = node;
+        return;
+      }
+      console.error(
+        `mergeRefs cannot handle Refs of type boolean, number or string, received ref ${String(
+          ref
+        )}`
+      );
+    });
+  };
+}