Allow multi-select on iOS Safari/touch devices (WordPress#63671)

packages/block-editor/src/components/block-list/use-block-props/use-focus-first-element.js

@@ -68,6 +68,7 @@ export function useFocusFirstElement( { clientId, initialPosition } ) {
 			textInputs[ isReverse ? textInputs.length - 1 : 0 ] || ref.current;
 
 		if ( ! isInsideRootBlock( ref.current, target ) ) {
+			ownerDocument.defaultView.getSelection().removeAllRanges();
 			ref.current.focus();
 			return;
 		}

packages/block-editor/src/components/rich-text/event-listeners/paste-handler.js

@@ -26,10 +26,15 @@ export default ( props ) => ( element ) => {
 			preserveWhiteSpace,
 			pastePlainText,
 		} = props.current;
+		const { ownerDocument } = element;
+		const { defaultView } = ownerDocument;
+		const { anchorNode, focusNode } = defaultView.getSelection();
+		const containsSelection =
+			element.contains( anchorNode ) && element.contains( focusNode );
 
 		// The event listener is attached to the window, so we need to check if
 		// the target is the element.
-		if ( event.target !== element ) {
+		if ( ! containsSelection ) {
 			return;
 		}
 

packages/block-editor/src/components/rich-text/index.js

@@ -357,7 +357,19 @@ export function RichTextWrapper(
 	const inputEvents = useRef( new Set() );
 
 	function onFocus() {
-		anchorRef.current?.focus();
+		let element = anchorRef.current;
+
+		if ( ! element ) {
+			return;
+		}
+
+		// Writing flow might be editable, so we should make sure focus goes to
+		// the root editable element.
+		while ( element.parentElement?.isContentEditable ) {
+			element = element.parentElement;
+		}
+
+		element.focus();
 	}
 
 	const registry = useRegistry();

packages/block-editor/src/components/writing-flow/index.js

@@ -23,6 +23,7 @@ import useSelectionObserver from './use-selection-observer';
 import useClickSelection from './use-click-selection';
 import useInput from './use-input';
 import useClipboardHandler from './use-clipboard-handler';
+import useEventRedirect from './use-event-redirect';
 import { store as blockEditorStore } from '../../store';
 
 export function useWritingFlow() {
@@ -65,6 +66,7 @@ export function useWritingFlow() {
 				},
 				[ hasMultiSelection ]
 			),
+			useEventRedirect(),
 		] ),
 		after,
 	];

packages/block-editor/src/components/writing-flow/use-arrow-nav.js

@@ -19,6 +19,7 @@ import { useRefEffect } from '@wordpress/compose';
  */
 import { getBlockClientId, isInSameBlock } from '../../utils/dom';
 import { store as blockEditorStore } from '../../store';
+import { getSelectionRoot } from './utils';
 
 /**
  * Returns true if the element should consider edge navigation upon a keyboard
@@ -190,8 +191,7 @@ export default function useArrowNav() {
 				return;
 			}
 
-			const { keyCode, target, shiftKey, ctrlKey, altKey, metaKey } =
-				event;
+			const { keyCode, shiftKey, ctrlKey, altKey, metaKey } = event;
 			const isUp = keyCode === UP;
 			const isDown = keyCode === DOWN;
 			const isLeft = keyCode === LEFT;
@@ -233,6 +233,11 @@ export default function useArrowNav() {
 				return;
 			}
 
+			const target =
+				ownerDocument.activeElement === node
+					? getSelectionRoot( ownerDocument )
+					: event.target;
+
 			// Abort if our current target is not a candidate for navigation
 			// (e.g. preserve native input behaviors).
 			if ( ! isNavigationCandidate( target, keyCode, hasModifier ) ) {
@@ -274,6 +279,7 @@ export default function useArrowNav() {
 				( altKey ? isHorizontalEdge( target, isReverseDir ) : true ) &&
 				! keepCaretInsideBlock
 			) {
+				node.contentEditable = false;
 				const closestTabbable = getClosestTabbable(
 					target,
 					isReverse,
@@ -297,6 +303,7 @@ export default function useArrowNav() {
 				isHorizontalEdge( target, isReverseDir ) &&
 				! keepCaretInsideBlock
 			) {
+				node.contentEditable = false;
 				const closestTabbable = getClosestTabbable(
 					target,
 					isReverseDir,

packages/block-editor/src/components/writing-flow/use-event-redirect.js

@@ -0,0 +1,72 @@
+/**
+ * WordPress dependencies
+ */
+import { useRefEffect } from '@wordpress/compose';
+
+/**
+ * Internal dependencies
+ */
+import { getSelectionRoot } from './utils';
+
+/**
+ * Whenever content editable is enabled on writing flow, it will have focus, so
+ * we need to dispatch some events to the root of the selection to ensure
+ * compatibility with rich text. In the future, perhaps the rich text event
+ * handlers should be attached to the window instead.
+ *
+ * Alternatively, we could try to find a way to always maintain rich text focus.
+ */
+export default function useEventRedirect() {
+	return useRefEffect( ( node ) => {
+		function onInput( event ) {
+			if ( event.target !== node ) {
+				return;
+			}
+
+			const { ownerDocument } = node;
+			const { defaultView } = ownerDocument;
+			const prototype = Object.getPrototypeOf( event );
+			const constructorName = prototype.constructor.name;
+			const Constructor = defaultView[ constructorName ];
+			const root = getSelectionRoot( ownerDocument );
+
+			if ( ! root || root === node ) {
+				return;
+			}
+
+			const init = {};
+
+			for ( const key in event ) {
+				init[ key ] = event[ key ];
+			}
+
+			init.bubbles = false;
+
+			const newEvent = new Constructor( event.type, init );
+			const cancelled = ! root.dispatchEvent( newEvent );
+
+			if ( cancelled ) {
+				event.preventDefault();
+			}
+		}
+
+		const events = [
+			'beforeinput',
+			'input',
+			'compositionstart',
+			'compositionend',
+			'compositionupdate',
+			'keydown',
+		];
+
+		events.forEach( ( eventType ) => {
+			node.addEventListener( eventType, onInput );
+		} );
+
+		return () => {
+			events.forEach( ( eventType ) => {
+				node.removeEventListener( eventType, onInput );
+			} );
+		};
+	}, [] );
+}

packages/block-editor/src/components/writing-flow/use-input.js

@@ -16,6 +16,7 @@ import {
  * Internal dependencies
  */
 import { store as blockEditorStore } from '../../store';
+import { getSelectionRoot } from './utils';
 
 /**
  * Handles input for selections across blocks.
@@ -49,7 +50,24 @@ export default function useInput() {
 			// DOM. This will cause React errors (and the DOM should only be
 			// altered in a controlled fashion).
 			if ( node.contentEditable === 'true' ) {
-				event.preventDefault();
+				const selection = node.ownerDocument.defaultView.getSelection();
+				const range = selection.rangeCount
+					? selection.getRangeAt( 0 )
+					: null;
+				const root = getSelectionRoot( node.ownerDocument );
+
+				// If selection is contained within a nested editable, allow
+				// input. We need to ensure that selection is maintained.
+				if ( root ) {
+					node.contentEditable = false;
+					root.focus();
+					selection.removeAllRanges();
+					if ( range ) {
+						selection.addRange( range );
+					}
+				} else {
+					event.preventDefault();
+				}
 			}
 		}
 
@@ -59,6 +77,23 @@ export default function useInput() {
 			}
 
 			if ( ! hasMultiSelection() ) {
+				const { ownerDocument } = node;
+				if ( node === ownerDocument.activeElement ) {
+					if ( event.key === 'End' || event.key === 'Home' ) {
+						const selectionRoot = getSelectionRoot( ownerDocument );
+						const selection =
+							ownerDocument.defaultView.getSelection();
+						selection.selectAllChildren( selectionRoot );
+						const method =
+							event.key === 'End'
+								? 'collapseToEnd'
+								: 'collapseToStart';
+						selection[ method ]();
+						event.preventDefault();
+						return;
+					}
+				}
+
 				if ( event.keyCode === ENTER ) {
 					if ( event.shiftKey || __unstableIsFullySelected() ) {
 						return;

packages/block-editor/src/components/writing-flow/use-select-all.js

@@ -10,6 +10,7 @@ import { useRefEffect } from '@wordpress/compose';
  * Internal dependencies
  */
 import { store as blockEditorStore } from '../../store';
+import { getSelectionRoot } from './utils';
 
 export default function useSelectAll() {
 	const { getBlockOrder, getSelectedBlockClientIds, getBlockRootClientId } =
@@ -23,12 +24,27 @@ export default function useSelectAll() {
 				return;
 			}
 
+			const selectionRoot = getSelectionRoot( node.ownerDocument );
 			const selectedClientIds = getSelectedBlockClientIds();
 
+			// Abort if there is selection, but it is not within a block.
+			if ( selectionRoot && ! selectedClientIds.length ) {
+				return;
+			}
+
 			if (
+				selectionRoot &&
 				selectedClientIds.length < 2 &&
-				! isEntirelySelected( event.target )
+				! isEntirelySelected( selectionRoot )
 			) {
+				if ( node === node.ownerDocument.activeElement ) {
+					event.preventDefault();
+					node.ownerDocument.defaultView
+						.getSelection()
+						.selectAllChildren( selectionRoot );
+					return;
+				}
+
 				return;
 			}
 
@@ -45,6 +61,7 @@ export default function useSelectAll() {
 					node.ownerDocument.defaultView
 						.getSelection()
 						.removeAllRanges();
+					node.contentEditable = 'false';
 					selectBlock( rootClientId );
 				}
 				return;

packages/block-editor/src/components/writing-flow/use-selection-observer.js

@@ -98,8 +98,12 @@ function getRichTextElement( node ) {
 export default function useSelectionObserver() {
 	const { multiSelect, selectBlock, selectionChange } =
 		useDispatch( blockEditorStore );
-	const { getBlockParents, getBlockSelectionStart, isMultiSelecting } =
-		useSelect( blockEditorStore );
+	const {
+		getBlockParents,
+		getBlockSelectionStart,
+		isMultiSelecting,
+		getSelectedBlockClientId,
+	} = useSelect( blockEditorStore );
 	return useRefEffect(
 		( node ) => {
 			const { ownerDocument } = node;
@@ -182,10 +186,17 @@ export default function useSelectionObserver() {
 					return;
 				}
 
+				setContentEditableWrapper(
+					node,
+					!! ( startClientId && endClientId )
+				);
+
 				const isSingularSelection = startClientId === endClientId;
 				if ( isSingularSelection ) {
 					if ( ! isMultiSelecting() ) {
-						selectBlock( startClientId );
+						if ( getSelectedBlockClientId() !== startClientId ) {
+							selectBlock( startClientId );
+						}
 					} else {
 						multiSelect( startClientId, startClientId );
 					}

packages/block-editor/src/components/writing-flow/utils.js

@@ -116,3 +116,33 @@ function toPlainText( html ) {
 	// Merge any consecutive line breaks
 	return plainText.replace( /\n\n+/g, '\n\n' );
 }
+
+/**
+ * Gets the current content editable root element based on the selection.
+ * @param {Document} ownerDocument
+ * @return {Element|undefined} The content editable root element.
+ */
+export function getSelectionRoot( ownerDocument ) {
+	const { defaultView } = ownerDocument;
+	const { anchorNode, focusNode } = defaultView.getSelection();
+
+	if ( ! anchorNode || ! focusNode ) {
+		return;
+	}
+
+	const anchorElement = (
+		anchorNode.nodeType === anchorNode.ELEMENT_NODE
+			? anchorNode
+			: anchorNode.parentElement
+	).closest( '[contenteditable]' );
+
+	if ( ! anchorElement ) {
+		return;
+	}
+
+	if ( ! anchorElement.contains( focusNode ) ) {
+		return;
+	}
+
+	return anchorElement;
+}

packages/dom/src/dom/place-caret-at-edge.js

@@ -67,7 +67,14 @@ export default function placeCaretAtEdge( container, isReverse, x ) {
 		return;
 	}
 
+	const { ownerDocument } = container;
+	const { defaultView } = ownerDocument;
+	assertIsDefined( defaultView, 'defaultView' );
+	const selection = defaultView.getSelection();
+	assertIsDefined( selection, 'selection' );
+
 	if ( ! container.isContentEditable ) {
+		selection.removeAllRanges();
 		return;
 	}
 
@@ -79,11 +86,6 @@ export default function placeCaretAtEdge( container, isReverse, x ) {
 		return;
 	}
 
-	const { ownerDocument } = container;
-	const { defaultView } = ownerDocument;
-	assertIsDefined( defaultView, 'defaultView' );
-	const selection = defaultView.getSelection();
-	assertIsDefined( selection, 'selection' );
 	selection.removeAllRanges();
 	selection.addRange( range );
 }