Components: Add HOF to ignore IME keydowns

packages/components/CHANGELOG.md

@@ -16,6 +16,7 @@
 -   Add lint rules for theme color CSS var usage ([#59022](https://github.com/WordPress/gutenberg/pull/59022)).
 -   `FormTokenField`: Use `Element.scrollIntoView()` instead of `dom-scroll-into-view` ([#59085](https://github.com/WordPress/gutenberg/pull/59085)).
 -   Removing `dom-scroll-into-view` as a dependency of the components package ([#59085](https://github.com/WordPress/gutenberg/pull/59085)).
+-   Add higher-order function to ignore IME keydowns ([#59081](https://github.com/WordPress/gutenberg/pull/59081)).
 
 ## 26.0.1 (2024-02-13)
 

packages/components/src/autocomplete/index.tsx

@@ -30,6 +30,7 @@ import { isAppleOS } from '@wordpress/keycodes';
  */
 import { getAutoCompleterUI } from './autocompleter-ui';
 import { escapeRegExp } from '../utils/strings';
+import { withIgnoreIMEEvents } from '../utils/with-ignore-ime-events';
 import type {
 	AutocompleteProps,
 	AutocompleterUIProps,
@@ -183,15 +184,7 @@ export function useAutocomplete( {
 			return;
 		}
 
-		if (
-			event.defaultPrevented ||
-			// Ignore keydowns from IMEs
-			event.isComposing ||
-			// Workaround for Mac Safari where the final Enter/Backspace of an IME composition
-			// is `isComposing=false`, even though it's technically still part of the composition.
-			// These can only be detected by keyCode.
-			event.keyCode === 229
-		) {
+		if ( event.defaultPrevented ) {
 			return;
 		}
 
@@ -390,7 +383,7 @@ export function useAutocomplete( {
 	return {
 		listBoxId,
 		activeId,
-		onKeyDown: handleKeyDown,
+		onKeyDown: withIgnoreIMEEvents( handleKeyDown ),
 		popover: hasSelection && AutocompleterUI && (
 			<AutocompleterUI
 				className={ className }

packages/components/src/combobox-control/index.tsx

@@ -33,6 +33,7 @@ import { normalizeTextString } from '../utils/strings';
 import type { ComboboxControlOption, ComboboxControlProps } from './types';
 import type { TokenInputProps } from '../form-token-field/types';
 import { useDeprecated36pxDefaultSizeProp } from '../utils/use-deprecated-props';
+import { withIgnoreIMEEvents } from '../utils/with-ignore-ime-events';
 
 const noop = () => {};
 
@@ -186,51 +187,42 @@ function ComboboxControl( props: ComboboxControlProps ) {
 		setIsExpanded( true );
 	};
 
-	const onKeyDown: React.KeyboardEventHandler< HTMLDivElement > = (
-		event
-	) => {
-		let preventDefault = false;
+	const onKeyDown: React.KeyboardEventHandler< HTMLDivElement > =
+		withIgnoreIMEEvents( ( event ) => {
+			let preventDefault = false;
 
-		if (
-			event.defaultPrevented ||
-			// Ignore keydowns from IMEs
-			event.nativeEvent.isComposing ||
-			// Workaround for Mac Safari where the final Enter/Backspace of an IME composition
-			// is `isComposing=false`, even though it's technically still part of the composition.
-			// These can only be detected by keyCode.
-			event.keyCode === 229
-		) {
-			return;
-		}
+			if ( event.defaultPrevented ) {
+				return;
+			}
 
-		switch ( event.code ) {
-			case 'Enter':
-				if ( selectedSuggestion ) {
-					onSuggestionSelected( selectedSuggestion );
+			switch ( event.code ) {
+				case 'Enter':
+					if ( selectedSuggestion ) {
+						onSuggestionSelected( selectedSuggestion );
+						preventDefault = true;
+					}
+					break;
+				case 'ArrowUp':
+					handleArrowNavigation( -1 );
 					preventDefault = true;
-				}
-				break;
-			case 'ArrowUp':
-				handleArrowNavigation( -1 );
-				preventDefault = true;
-				break;
-			case 'ArrowDown':
-				handleArrowNavigation( 1 );
-				preventDefault = true;
-				break;
-			case 'Escape':
-				setIsExpanded( false );
-				setSelectedSuggestion( null );
-				preventDefault = true;
-				break;
-			default:
-				break;
-		}
+					break;
+				case 'ArrowDown':
+					handleArrowNavigation( 1 );
+					preventDefault = true;
+					break;
+				case 'Escape':
+					setIsExpanded( false );
+					setSelectedSuggestion( null );
+					preventDefault = true;
+					break;
+				default:
+					break;
+			}
 
-		if ( preventDefault ) {
-			event.preventDefault();
-		}
-	};
+			if ( preventDefault ) {
+				event.preventDefault();
+			}
+		} );
 
 	const onBlur = () => {
 		setInputHasFocus( false );

packages/components/src/form-token-field/index.tsx

@@ -28,6 +28,7 @@ import {
 } from '../base-control/styles/base-control-styles';
 import { Spacer } from '../spacer';
 import { useDeprecated36pxDefaultSizeProp } from '../utils/use-deprecated-props';
+import { withIgnoreIMEEvents } from '../utils/with-ignore-ime-events';
 
 const identity = ( value: string ) => value;
 
@@ -194,15 +195,7 @@ export function FormTokenField( props: FormTokenFieldProps ) {
 	function onKeyDown( event: KeyboardEvent ) {
 		let preventDefault = false;
 
-		if (
-			event.defaultPrevented ||
-			// Ignore keydowns from IMEs
-			event.nativeEvent.isComposing ||
-			// Workaround for Mac Safari where the final Enter/Backspace of an IME composition
-			// is `isComposing=false`, even though it's technically still part of the composition.
-			// These can only be detected by keyCode.
-			event.keyCode === 229
-		) {
+		if ( event.defaultPrevented ) {
 			return;
 		}
 		switch ( event.key ) {
@@ -689,7 +682,7 @@ export function FormTokenField( props: FormTokenFieldProps ) {
 
 	if ( ! disabled ) {
 		tokenFieldProps = Object.assign( {}, tokenFieldProps, {
-			onKeyDown,
+			onKeyDown: withIgnoreIMEEvents( onKeyDown ),
 			onKeyPress,
 			onFocus: onFocusHandler,
 		} );

packages/components/src/modal/index.tsx

@@ -41,6 +41,7 @@ import * as ariaHelper from './aria-helper';
 import Button from '../button';
 import StyleProvider from '../style-provider';
 import type { ModalProps } from './types';
+import { withIgnoreIMEEvents } from '../utils/with-ignore-ime-events';
 
 // Used to track and dismiss the prior modal when another opens unless nested.
 const ModalContext = createContext<
@@ -196,17 +197,6 @@ function UnforwardedModal(
 	}, [ isContentScrollable, childrenContainerRef ] );
 
 	function handleEscapeKeyDown( event: KeyboardEvent< HTMLDivElement > ) {
-		if (
-			// Ignore keydowns from IMEs
-			event.nativeEvent.isComposing ||
-			// Workaround for Mac Safari where the final Enter/Backspace of an IME composition
-			// is `isComposing=false`, even though it's technically still part of the composition.
-			// These can only be detected by keyCode.
-			event.keyCode === 229
-		) {
-			return;
-		}
-
 		if (
 			shouldCloseOnEsc &&
 			( event.code === 'Escape' || event.key === 'Escape' ) &&
@@ -265,7 +255,7 @@ function UnforwardedModal(
 				'components-modal__screen-overlay',
 				overlayClassName
 			) }
-			onKeyDown={ handleEscapeKeyDown }
+			onKeyDown={ withIgnoreIMEEvents( handleEscapeKeyDown ) }
 			{ ...( shouldCloseOnClickOutside ? overlayPressHandlers : {} ) }
 		>
 			<StyleProvider document={ document }>

packages/components/src/utils/with-ignore-ime-events.ts

@@ -0,0 +1,32 @@
+/**
+ * A higher-order function that wraps a keydown event handler to ensure it is not an IME event.
+ *
+ * In CJK languages, an IME (Input Method Editor) is used to input complex characters.
+ * During an IME composition, keydown events (e.g. Enter or Escape) can be fired
+ * which are intended to control the IME and not the application.
+ * These events should be ignored by any application logic.
+ *
+ * @param keydownHandler The keydown event handler to execute after ensuring it was not an IME event.
+ *
+ * @return A wrapped version of the given event handler that ignores IME events.
+ */
+export function withIgnoreIMEEvents<
+	E extends React.KeyboardEvent | KeyboardEvent,
+>( keydownHandler: ( event: E ) => void ) {
+	return ( event: E ) => {
+		const { isComposing } =
+			'nativeEvent' in event ? event.nativeEvent : event;
+
+		if (
+			isComposing ||
+			// Workaround for Mac Safari where the final Enter/Backspace of an IME composition
+			// is `isComposing=false`, even though it's technically still part of the composition.
+			// These can only be detected by keyCode.
+			event.keyCode === 229
+		) {
+			return;
+		}
+
+		keydownHandler( event );
+	};
+}