From ebc299fc2f21a74fffa3f8aa2209259d98702156 Mon Sep 17 00:00:00 2001
From: Dominic Gannaway <trueadm@users.noreply.github.com>
Date: Tue, 24 Sep 2019 23:26:20 +0200
Subject: [PATCH] [react-interactions] TabFocus -> FocusManager (#16874)

---
 .../{tab-focus.js => focus-manager.js}        |   2 +-
 .../accessibility/src/FocusManager.js         | 114 +++++++++++++++++
 .../accessibility/src/TabFocus.js             |  67 ----------
 ...ernal.js => FocusManager-test.internal.js} | 118 ++++++++++++------
 .../events/src/dom/Focus.js                   |  46 ++++++-
 scripts/rollup/bundles.js                     |   6 +-
 6 files changed, 242 insertions(+), 111 deletions(-)
 rename packages/react-interactions/accessibility/{tab-focus.js => focus-manager.js} (81%)
 create mode 100644 packages/react-interactions/accessibility/src/FocusManager.js
 delete mode 100644 packages/react-interactions/accessibility/src/TabFocus.js
 rename packages/react-interactions/accessibility/src/__tests__/{TabFocus-test.internal.js => FocusManager-test.internal.js} (75%)

diff --git a/packages/react-interactions/accessibility/tab-focus.js b/packages/react-interactions/accessibility/focus-manager.js
similarity index 81%
rename from packages/react-interactions/accessibility/tab-focus.js
rename to packages/react-interactions/accessibility/focus-manager.js
index 493333ccad3f6..56d396157c226 100644
--- a/packages/react-interactions/accessibility/tab-focus.js
+++ b/packages/react-interactions/accessibility/focus-manager.js
@@ -9,4 +9,4 @@
 
 'use strict';
 
-module.exports = require('./src/TabFocus');
+module.exports = require('./src/FocusManager');
diff --git a/packages/react-interactions/accessibility/src/FocusManager.js b/packages/react-interactions/accessibility/src/FocusManager.js
new file mode 100644
index 0000000000000..34d4b9e44cfcc
--- /dev/null
+++ b/packages/react-interactions/accessibility/src/FocusManager.js
@@ -0,0 +1,114 @@
+/**
+ * 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
+ */
+
+import type {ReactScope} from 'shared/ReactTypes';
+import type {KeyboardEvent} from 'react-interactions/events/keyboard';
+
+import React from 'react';
+import {useKeyboard} from 'react-interactions/events/keyboard';
+import {useFocusWithin} from 'react-interactions/events/focus';
+import {
+  focusFirst,
+  focusPrevious,
+  focusNext,
+} from 'react-interactions/accessibility/focus-control';
+import TabbableScope from 'react-interactions/accessibility/tabbable-scope';
+
+type TabFocusProps = {|
+  autoFocus?: boolean,
+  children: React.Node,
+  containFocus?: boolean,
+  restoreFocus?: boolean,
+  scope: ReactScope,
+|};
+
+const {useLayoutEffect, useRef} = React;
+
+const FocusManager = React.forwardRef(
+  (
+    {
+      autoFocus,
+      children,
+      containFocus,
+      restoreFocus,
+      scope: CustomScope,
+    }: TabFocusProps,
+    ref,
+  ): React.Node => {
+    const ScopeToUse = CustomScope || TabbableScope;
+    const scopeRef = useRef(null);
+    // This ensures tabbing works through the React tree (including Portals and Suspense nodes)
+    const keyboard = useKeyboard({
+      onKeyDown(event: KeyboardEvent): void {
+        if (event.key !== 'Tab') {
+          event.continuePropagation();
+          return;
+        }
+        const scope = scopeRef.current;
+        if (scope !== null) {
+          if (event.shiftKey) {
+            focusPrevious(scope, event, containFocus);
+          } else {
+            focusNext(scope, event, containFocus);
+          }
+        }
+      },
+    });
+    const focusWithin = useFocusWithin({
+      onBlurWithin: function(event) {
+        if (!containFocus) {
+          event.continuePropagation();
+        }
+        const lastNode = event.target;
+        if (lastNode) {
+          requestAnimationFrame(() => {
+            (lastNode: any).focus();
+          });
+        }
+      },
+    });
+    useLayoutEffect(
+      () => {
+        const scope = scopeRef.current;
+        let restoreElem;
+        if (restoreFocus) {
+          restoreElem = document.activeElement;
+        }
+        if (autoFocus && scope !== null) {
+          focusFirst(scope);
+        }
+        if (restoreElem) {
+          return () => {
+            (restoreElem: any).focus();
+          };
+        }
+      },
+      [scopeRef],
+    );
+
+    return (
+      <ScopeToUse
+        ref={node => {
+          if (ref) {
+            if (typeof ref === 'function') {
+              ref(node);
+            } else {
+              ref.current = node;
+            }
+          }
+          scopeRef.current = node;
+        }}
+        listeners={[keyboard, focusWithin]}>
+        {children}
+      </ScopeToUse>
+    );
+  },
+);
+
+export default FocusManager;
diff --git a/packages/react-interactions/accessibility/src/TabFocus.js b/packages/react-interactions/accessibility/src/TabFocus.js
deleted file mode 100644
index 76e528116cd2e..0000000000000
--- a/packages/react-interactions/accessibility/src/TabFocus.js
+++ /dev/null
@@ -1,67 +0,0 @@
-/**
- * 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
- */
-
-import type {ReactScope} from 'shared/ReactTypes';
-import type {KeyboardEvent} from 'react-interactions/events/keyboard';
-
-import React from 'react';
-import {useKeyboard} from 'react-interactions/events/keyboard';
-import {
-  focusPrevious,
-  focusNext,
-} from 'react-interactions/accessibility/focus-control';
-
-type TabFocusProps = {
-  children: React.Node,
-  contain?: boolean,
-  scope: ReactScope,
-};
-
-const {useRef} = React;
-
-const TabFocus = React.forwardRef(
-  ({children, contain, scope: Scope}: TabFocusProps, ref): React.Node => {
-    const scopeRef = useRef(null);
-    const keyboard = useKeyboard({
-      onKeyDown(event: KeyboardEvent): void {
-        if (event.key !== 'Tab') {
-          event.continuePropagation();
-          return;
-        }
-        const scope = scopeRef.current;
-        if (scope !== null) {
-          if (event.shiftKey) {
-            focusPrevious(scope, event, contain);
-          } else {
-            focusNext(scope, event, contain);
-          }
-        }
-      },
-    });
-
-    return (
-      <Scope
-        ref={node => {
-          if (ref) {
-            if (typeof ref === 'function') {
-              ref(node);
-            } else {
-              ref.current = node;
-            }
-          }
-          scopeRef.current = node;
-        }}
-        listeners={keyboard}>
-        {children}
-      </Scope>
-    );
-  },
-);
-
-export default TabFocus;
diff --git a/packages/react-interactions/accessibility/src/__tests__/TabFocus-test.internal.js b/packages/react-interactions/accessibility/src/__tests__/FocusManager-test.internal.js
similarity index 75%
rename from packages/react-interactions/accessibility/src/__tests__/TabFocus-test.internal.js
rename to packages/react-interactions/accessibility/src/__tests__/FocusManager-test.internal.js
index 92a2833b9c43c..1cf07104c0f37 100644
--- a/packages/react-interactions/accessibility/src/__tests__/TabFocus-test.internal.js
+++ b/packages/react-interactions/accessibility/src/__tests__/FocusManager-test.internal.js
@@ -11,18 +11,16 @@ import {createEventTarget} from 'react-interactions/events/src/dom/testing-libra
 
 let React;
 let ReactFeatureFlags;
-let TabFocus;
-let TabbableScope;
+let FocusManager;
 let FocusControl;
 
-describe('TabFocusController', () => {
+describe('FocusManager', () => {
   beforeEach(() => {
     jest.resetModules();
     ReactFeatureFlags = require('shared/ReactFeatureFlags');
     ReactFeatureFlags.enableScopeAPI = true;
     ReactFeatureFlags.enableFlareAPI = true;
-    TabFocus = require('../TabFocus').default;
-    TabbableScope = require('../TabbableScope').default;
+    FocusManager = require('../FocusManager').default;
     FocusControl = require('../FocusControl');
     React = require('react');
   });
@@ -42,21 +40,21 @@ describe('TabFocusController', () => {
       container = null;
     });
 
-    it('handles tab operations', () => {
+    it('handles tab operations by default', () => {
       const inputRef = React.createRef();
       const input2Ref = React.createRef();
       const buttonRef = React.createRef();
-      const butto2nRef = React.createRef();
+      const button2Ref = React.createRef();
       const divRef = React.createRef();
 
       const Test = () => (
-        <TabFocus scope={TabbableScope}>
+        <FocusManager>
           <input ref={inputRef} />
           <button ref={buttonRef} />
           <div ref={divRef} tabIndex={0} />
           <input ref={input2Ref} tabIndex={-1} />
-          <button ref={butto2nRef} />
-        </TabFocus>
+          <button ref={button2Ref} />
+        </FocusManager>
       );
 
       ReactDOM.render(<Test />, container);
@@ -66,24 +64,67 @@ describe('TabFocusController', () => {
       createEventTarget(document.activeElement).tabNext();
       expect(document.activeElement).toBe(divRef.current);
       createEventTarget(document.activeElement).tabNext();
-      expect(document.activeElement).toBe(butto2nRef.current);
+      expect(document.activeElement).toBe(button2Ref.current);
       createEventTarget(document.activeElement).tabPrevious();
       expect(document.activeElement).toBe(divRef.current);
     });
 
-    it('handles tab operations with containment', () => {
+    it('handles autoFocus', () => {
+      const buttonRef = React.createRef();
+
+      const Test = () => (
+        <FocusManager autoFocus={true}>
+          <input tabIndex={-1} />
+          <button ref={buttonRef} />
+        </FocusManager>
+      );
+
+      ReactDOM.render(<Test />, container);
+      expect(document.activeElement).toBe(buttonRef.current);
+    });
+
+    it('handles restoreFocus', () => {
+      const difRef = React.createRef();
+      const buttonRef = React.createRef();
+
+      const Test = ({flag}) => {
+        return (
+          <div ref={difRef} tabIndex={0}>
+            {flag ? (
+              <FocusManager autoFocus={true} restoreFocus={true}>
+                <button ref={buttonRef} />
+              </FocusManager>
+            ) : null}
+          </div>
+        );
+      };
+
+      ReactDOM.render(<Test flag={false} />, container);
+      difRef.current.focus();
+      expect(document.activeElement).toBe(difRef.current);
+      ReactDOM.render(<Test flag={true} />, container);
+      expect(document.activeElement).toBe(buttonRef.current);
+      ReactDOM.render(<Test flag={false} />, container);
+      expect(document.activeElement).toBe(difRef.current);
+    });
+
+    it('handles containFocus', () => {
       const inputRef = React.createRef();
       const input2Ref = React.createRef();
+      const input3Ref = React.createRef();
       const buttonRef = React.createRef();
       const button2Ref = React.createRef();
 
       const Test = () => (
-        <TabFocus scope={TabbableScope} contain={true}>
-          <input ref={inputRef} tabIndex={-1} />
-          <button ref={buttonRef} id={1} />
-          <button ref={button2Ref} id={2} />
-          <input ref={input2Ref} tabIndex={-1} />
-        </TabFocus>
+        <div>
+          <FocusManager containFocus={true}>
+            <input ref={inputRef} tabIndex={-1} />
+            <button ref={buttonRef} id={1} />
+            <button ref={button2Ref} id={2} />
+            <input ref={input2Ref} tabIndex={-1} />
+          </FocusManager>
+          <input ref={input3Ref} />
+        </div>
       );
 
       ReactDOM.render(<Test />, container);
@@ -98,9 +139,16 @@ describe('TabFocusController', () => {
       expect(document.activeElement).toBe(buttonRef.current);
       createEventTarget(document.activeElement).tabPrevious();
       expect(document.activeElement).toBe(button2Ref.current);
+      // Focus should be restored to the contained area
+      const rAF = window.requestAnimationFrame;
+      window.requestAnimationFrame = x => setTimeout(x);
+      input3Ref.current.focus();
+      jest.advanceTimersByTime(1);
+      window.requestAnimationFrame = rAF;
+      expect(document.activeElement).toBe(button2Ref.current);
     });
 
-    it('handles tab operations when controllers are nested', () => {
+    it('works with nested FocusManagers', () => {
       const inputRef = React.createRef();
       const input2Ref = React.createRef();
       const buttonRef = React.createRef();
@@ -109,16 +157,16 @@ describe('TabFocusController', () => {
       const button4Ref = React.createRef();
 
       const Test = () => (
-        <TabFocus scope={TabbableScope}>
+        <FocusManager>
           <input ref={inputRef} tabIndex={-1} />
           <button ref={buttonRef} id={1} />
-          <TabFocus scope={TabbableScope}>
+          <FocusManager>
             <button ref={button2Ref} id={2} />
             <button ref={button3Ref} id={3} />
-          </TabFocus>
+          </FocusManager>
           <input ref={input2Ref} tabIndex={-1} />
           <button ref={button4Ref} id={4} />
-        </TabFocus>
+        </FocusManager>
       );
 
       ReactDOM.render(<Test />, container);
@@ -136,7 +184,7 @@ describe('TabFocusController', () => {
       expect(document.activeElement).toBe(button2Ref.current);
     });
 
-    it('handles tab operations when controllers are nested with containment', () => {
+    it('handles containFocus (nested FocusManagers)', () => {
       const inputRef = React.createRef();
       const input2Ref = React.createRef();
       const buttonRef = React.createRef();
@@ -145,16 +193,16 @@ describe('TabFocusController', () => {
       const button4Ref = React.createRef();
 
       const Test = () => (
-        <TabFocus scope={TabbableScope}>
+        <FocusManager>
           <input ref={inputRef} tabIndex={-1} />
           <button ref={buttonRef} id={1} />
-          <TabFocus contain={true} scope={TabbableScope}>
+          <FocusManager containFocus={true}>
             <button ref={button2Ref} id={2} />
             <button ref={button3Ref} id={3} />
-          </TabFocus>
+          </FocusManager>
           <input ref={input2Ref} tabIndex={-1} />
           <button ref={button4Ref} id={4} />
-        </TabFocus>
+        </FocusManager>
       );
 
       ReactDOM.render(<Test />, container);
@@ -195,14 +243,14 @@ describe('TabFocusController', () => {
       }
 
       const Test = () => (
-        <TabFocus scope={TabbableScope}>
+        <FocusManager>
           <button ref={buttonRef} id={1} />
           <button ref={button2Ref} id={2} />
           <React.Suspense fallback={<button ref={button3Ref} id={3} />}>
             <Component />
           </React.Suspense>
           <button ref={button4Ref} id={4} />
-        </TabFocus>
+        </FocusManager>
       );
 
       ReactDOM.render(<Test />, container);
@@ -220,7 +268,7 @@ describe('TabFocusController', () => {
       expect(document.activeElement).toBe(button2Ref.current);
     });
 
-    it('allows for imperative tab focus control', () => {
+    it('allows for imperative tab focus control using FocusControl', () => {
       const firstFocusControllerRef = React.createRef();
       const secondFocusControllerRef = React.createRef();
       const buttonRef = React.createRef();
@@ -229,16 +277,16 @@ describe('TabFocusController', () => {
 
       const Test = () => (
         <div>
-          <TabFocus ref={firstFocusControllerRef} scope={TabbableScope}>
+          <FocusManager ref={firstFocusControllerRef}>
             <input tabIndex={-1} />
             <button ref={buttonRef} />
             <button ref={button2Ref} />
             <input tabIndex={-1} />
-          </TabFocus>
-          <TabFocus ref={secondFocusControllerRef} scope={TabbableScope}>
+          </FocusManager>
+          <FocusManager ref={secondFocusControllerRef}>
             <input tabIndex={-1} />
             <div ref={divRef} tabIndex={0} />
-          </TabFocus>
+          </FocusManager>
         </div>
       );
 
diff --git a/packages/react-interactions/events/src/dom/Focus.js b/packages/react-interactions/events/src/dom/Focus.js
index d3d98e7ccb32a..8ae33233ad33e 100644
--- a/packages/react-interactions/events/src/dom/Focus.js
+++ b/packages/react-interactions/events/src/dom/Focus.js
@@ -26,6 +26,7 @@ type FocusEvent = {|
   type: FocusEventType | FocusWithinEventType,
   pointerType: PointerType,
   timeStamp: number,
+  continuePropagation: () => void,
 |};
 
 type FocusState = {
@@ -47,12 +48,16 @@ type FocusProps = {
 type FocusEventType = 'focus' | 'blur' | 'focuschange' | 'focusvisiblechange';
 
 type FocusWithinProps = {
-  disabled: boolean,
-  onFocusWithinChange: boolean => void,
-  onFocusWithinVisibleChange: boolean => void,
+  disabled?: boolean,
+  onBlurWithin?: (e: FocusEvent) => void,
+  onFocusWithinChange?: boolean => void,
+  onFocusWithinVisibleChange?: boolean => void,
 };
 
-type FocusWithinEventType = 'focuswithinvisiblechange' | 'focuswithinchange';
+type FocusWithinEventType =
+  | 'focuswithinvisiblechange'
+  | 'focuswithinchange'
+  | 'blurwithin';
 
 /**
  * Shared between Focus and FocusWithin
@@ -89,6 +94,14 @@ function createFocusEvent(
     type,
     pointerType,
     timeStamp: context.getTimeStamp(),
+    // We don't use stopPropagation, as the default behavior
+    // is to not propagate. Plus, there might be confusion
+    // using stopPropagation as we don't actually stop
+    // native propagation from working, but instead only
+    // allow propagation to the others keyboard responders.
+    continuePropagation() {
+      context.continuePropagation();
+    },
   };
 }
 
@@ -226,6 +239,26 @@ function dispatchBlurEvents(
   }
 }
 
+function dispatchBlurWithinEvents(
+  context: ReactDOMResponderContext,
+  event: ReactDOMResponderEvent,
+  props: FocusWithinProps,
+  state: FocusState,
+) {
+  const pointerType = state.pointerType;
+  const target = ((state.focusTarget: any): Element | Document) || event.target;
+  const onBlurWithin = (props.onBlurWithin: any);
+  if (isFunction(onBlurWithin)) {
+    const syntheticEvent = createFocusEvent(
+      context,
+      'blurwithin',
+      target,
+      pointerType,
+    );
+    context.dispatchEvent(syntheticEvent, onBlurWithin, DiscreteEvent);
+  }
+}
+
 function dispatchFocusChange(
   context: ReactDOMResponderContext,
   props: FocusProps,
@@ -364,7 +397,7 @@ function dispatchFocusWithinChangeEvent(
   state: FocusState,
   value: boolean,
 ) {
-  const onFocusWithinChange = props.onFocusWithinChange;
+  const onFocusWithinChange = (props.onFocusWithinChange: any);
   if (isFunction(onFocusWithinChange)) {
     context.dispatchEvent(value, onFocusWithinChange, DiscreteEvent);
   }
@@ -379,7 +412,7 @@ function dispatchFocusWithinVisibleChangeEvent(
   state: FocusState,
   value: boolean,
 ) {
-  const onFocusWithinVisibleChange = props.onFocusWithinVisibleChange;
+  const onFocusWithinVisibleChange = (props.onFocusWithinVisibleChange: any);
   if (isFunction(onFocusWithinVisibleChange)) {
     context.dispatchEvent(value, onFocusWithinVisibleChange, DiscreteEvent);
   }
@@ -447,6 +480,7 @@ const focusWithinResponderImpl = {
           !context.isTargetWithinResponder(relatedTarget)
         ) {
           dispatchFocusWithinChangeEvent(context, props, state, false);
+          dispatchBlurWithinEvents(context, event, props, state);
           state.isFocused = false;
         }
         break;
diff --git a/scripts/rollup/bundles.js b/scripts/rollup/bundles.js
index 1d36a8c163a7a..72d753937811f 100644
--- a/scripts/rollup/bundles.js
+++ b/scripts/rollup/bundles.js
@@ -681,11 +681,12 @@ const bundles = [
   {
     bundleTypes: [NODE_DEV, NODE_PROD, FB_WWW_DEV, FB_WWW_PROD],
     moduleType: NON_FIBER_RENDERER,
-    entry: 'react-interactions/accessibility/tab-focus',
-    global: 'ReactTabFocus',
+    entry: 'react-interactions/accessibility/focus-manager',
+    global: 'ReactFocusManager',
     externals: [
       'react',
       'react-interactions/events/keyboard',
+      'react-interactions/events/focus',
       'react-interactions/accessibility/tabbable-scope',
       'react-interactions/accessibility/focus-control',
     ],
@@ -721,6 +722,7 @@ const bundles = [
 ];
 
 const fbBundleExternalsMap = {
+  'react-interactions/events/focus': 'ReactEventsFocus',
   'react-interactions/events/keyboard': 'ReactEventsKeyboard',
   'react-interactions/events/tap': 'ReactEventsTap',
   'react-interactions/accessibility/tabbable-scope': 'ReactTabbableScope',