[Multi-selection]: Copy/cut partial selected blocks (#40098)

* [Multi-selection]: Copy/cut partial selected blocks

* handle `copy` button in block actions

* merge blocks on cut

* partial copy from block actions only when is mergeable

* update selector

* revert partial selection copy in block actions menu item

* add jsdoc for mapRichTextSettings util

* update tests

* add new e2e tests + pressKeyTimes playwright util

packages/block-editor/src/components/copy-handler/index.js

@@ -78,10 +78,17 @@ export function useClipboardHandler() {
 		getSelectedBlockClientIds,
 		hasMultiSelection,
 		getSettings,
+		__unstableIsFullySelected,
+		__unstableIsSelectionMergeable,
+		__unstableGetSelectedBlocksWithPartialSelection,
 	} = useSelect( blockEditorStore );
-	const { flashBlock, removeBlocks, replaceBlocks } = useDispatch(
-		blockEditorStore
-	);
+	const {
+		flashBlock,
+		removeBlocks,
+		replaceBlocks,
+		__unstableDeleteSelection,
+		__unstableExpandSelection,
+	} = useDispatch( blockEditorStore );
 	const notifyCopy = useNotifyCopy();
 
 	return useRefEffect( ( node ) => {
@@ -116,20 +123,53 @@ export function useClipboardHandler() {
 			const eventDefaultPrevented = event.defaultPrevented;
 			event.preventDefault();
 
+			const isFullySelected = __unstableIsFullySelected();
+			const isSelectionMergeable = __unstableIsSelectionMergeable();
+			const expandSelectionIsNeeded =
+				! isFullySelected && ! isSelectionMergeable;
 			if ( event.type === 'copy' || event.type === 'cut' ) {
 				if ( selectedBlockClientIds.length === 1 ) {
 					flashBlock( selectedBlockClientIds[ 0 ] );
 				}
-				notifyCopy( event.type, selectedBlockClientIds );
-				const blocks = getBlocksByClientId( selectedBlockClientIds );
-				const serialized = serialize( blocks );
-
-				event.clipboardData.setData( 'text/plain', serialized );
-				event.clipboardData.setData( 'text/html', serialized );
+				// If we have a partial selection that is not mergeable, just
+				// expand the selection to the whole blocks.
+				if ( expandSelectionIsNeeded ) {
+					__unstableExpandSelection();
+				} else {
+					notifyCopy( event.type, selectedBlockClientIds );
+					let blocks;
+					// Check if we have partial selection.
+					if ( isFullySelected ) {
+						blocks = getBlocksByClientId( selectedBlockClientIds );
+					} else {
+						const [
+							head,
+							tail,
+						] = __unstableGetSelectedBlocksWithPartialSelection();
+						const inBetweenBlocks = getBlocksByClientId(
+							selectedBlockClientIds.slice(
+								1,
+								selectedBlockClientIds.length - 1
+							)
+						);
+						blocks = [ head, ...inBetweenBlocks, tail ];
+					}
+					const serialized = serialize( blocks );
+
+					event.clipboardData.setData( 'text/plain', serialized );
+					event.clipboardData.setData( 'text/html', serialized );
+				}
 			}
 
 			if ( event.type === 'cut' ) {
-				removeBlocks( selectedBlockClientIds );
+				// We need to also check if at the start we needed to
+				// expand the selection, as in this point we might have
+				// programmatically fully selected the blocks above.
+				if ( isFullySelected && ! expandSelectionIsNeeded ) {
+					removeBlocks( selectedBlockClientIds );
+				} else {
+					__unstableDeleteSelection();
+				}
 			} else if ( event.type === 'paste' ) {
 				if ( eventDefaultPrevented ) {
 					// This was likely already handled in rich-text/use-paste-handler.js.

packages/block-editor/src/store/actions.js

@@ -22,6 +22,11 @@ import { __, _n, sprintf } from '@wordpress/i18n';
 import { create, insert, remove, toHTMLString } from '@wordpress/rich-text';
 import deprecated from '@wordpress/deprecated';
 
+/**
+ * Internal dependencies
+ */
+import { mapRichTextSettings } from './utils';
+
 /**
  * Action which will insert a default block insert action if there
  * are no other blocks at the root of the editor. This action should be used
@@ -667,19 +672,6 @@ export const synchronizeTemplate = () => ( { select, dispatch } ) => {
 	dispatch.resetBlocks( updatedBlockList );
 };
 
-function mapRichTextSettings( attributeDefinition ) {
-	const {
-		multiline: multilineTag,
-		__unstableMultilineWrapperTags: multilineWrapperTags,
-		__unstablePreserveWhiteSpace: preserveWhiteSpace,
-	} = attributeDefinition;
-	return {
-		multilineTag,
-		multilineWrapperTags,
-		preserveWhiteSpace,
-	};
-}
-
 /**
  * Delete the current selection.
  *

packages/block-editor/src/store/selectors.js

@@ -33,6 +33,12 @@ import { Platform } from '@wordpress/element';
 import { applyFilters } from '@wordpress/hooks';
 import { symbol } from '@wordpress/icons';
 import { __ } from '@wordpress/i18n';
+import { create, remove, toHTMLString } from '@wordpress/rich-text';
+
+/**
+ * Internal dependencies
+ */
+import { mapRichTextSettings } from './utils';
 
 /**
  * A block selection object.
@@ -1004,6 +1010,107 @@ export function __unstableIsSelectionMergeable( state, isForward ) {
 	return blocksToMerge && blocksToMerge.length;
 }
 
+/**
+ * Get partial selected blocks with their content updated
+ * based on the selection.
+ *
+ * @param {Object} state Editor state.
+ *
+ * @return {Object[]} Updated partial selected blocks.
+ */
+export const __unstableGetSelectedBlocksWithPartialSelection = ( state ) => {
+	const selectionAnchor = getSelectionStart( state );
+	const selectionFocus = getSelectionEnd( state );
+
+	if ( selectionAnchor.clientId === selectionFocus.clientId ) {
+		return EMPTY_ARRAY;
+	}
+
+	// Can't split if the selection is not set.
+	if (
+		! selectionAnchor.attributeKey ||
+		! selectionFocus.attributeKey ||
+		typeof selectionAnchor.offset === 'undefined' ||
+		typeof selectionFocus.offset === 'undefined'
+	) {
+		return EMPTY_ARRAY;
+	}
+
+	const anchorRootClientId = getBlockRootClientId(
+		state,
+		selectionAnchor.clientId
+	);
+	const focusRootClientId = getBlockRootClientId(
+		state,
+		selectionFocus.clientId
+	);
+
+	// It's not splittable if the selection doesn't start and end in the same
+	// block list. Maybe in the future it should be allowed.
+	if ( anchorRootClientId !== focusRootClientId ) {
+		return EMPTY_ARRAY;
+	}
+
+	const blockOrder = getBlockOrder( state, anchorRootClientId );
+	const anchorIndex = blockOrder.indexOf( selectionAnchor.clientId );
+	const focusIndex = blockOrder.indexOf( selectionFocus.clientId );
+
+	// Reassign selection start and end based on order.
+	const [ selectionStart, selectionEnd ] =
+		anchorIndex > focusIndex
+			? [ selectionFocus, selectionAnchor ]
+			: [ selectionAnchor, selectionFocus ];
+
+	const blockA = getBlock( state, selectionStart.clientId );
+	const blockAType = getBlockType( blockA.name );
+
+	const blockB = getBlock( state, selectionEnd.clientId );
+	const blockBType = getBlockType( blockB.name );
+
+	const htmlA = blockA.attributes[ selectionStart.attributeKey ];
+	const htmlB = blockB.attributes[ selectionEnd.attributeKey ];
+
+	const attributeDefinitionA =
+		blockAType.attributes[ selectionStart.attributeKey ];
+	const attributeDefinitionB =
+		blockBType.attributes[ selectionEnd.attributeKey ];
+
+	let valueA = create( {
+		html: htmlA,
+		...mapRichTextSettings( attributeDefinitionA ),
+	} );
+	let valueB = create( {
+		html: htmlB,
+		...mapRichTextSettings( attributeDefinitionB ),
+	} );
+
+	valueA = remove( valueA, 0, selectionStart.offset );
+	valueB = remove( valueB, selectionEnd.offset, valueB.text.length );
+
+	return [
+		{
+			...blockA,
+			attributes: {
+				...blockA.attributes,
+				[ selectionStart.attributeKey ]: toHTMLString( {
+					value: valueA,
+					...mapRichTextSettings( attributeDefinitionA ),
+				} ),
+			},
+		},
+		{
+			...blockB,
+			attributes: {
+				...blockB.attributes,
+				[ selectionEnd.attributeKey ]: toHTMLString( {
+					value: valueB,
+					...mapRichTextSettings( attributeDefinitionB ),
+				} ),
+			},
+		},
+	];
+};
+
 /**
  * Returns an array containing all block client IDs in the editor in the order
  * they appear. Optionally accepts a root client ID of the block list for which

packages/block-editor/src/store/utils.js

@@ -0,0 +1,19 @@
+/**
+ * Helper function that maps attribute definition properties to the
+ * ones used by RichText utils like `create, toHTMLString, etc..`.
+ *
+ * @param {Object} attributeDefinition A block's attribute definition object.
+ * @return {Object} The mapped object.
+ */
+export function mapRichTextSettings( attributeDefinition ) {
+	const {
+		multiline: multilineTag,
+		__unstableMultilineWrapperTags: multilineWrapperTags,
+		__unstablePreserveWhiteSpace: preserveWhiteSpace,
+	} = attributeDefinition;
+	return {
+		multilineTag,
+		multilineWrapperTags,
+		preserveWhiteSpace,
+	};
+}

packages/e2e-test-utils-playwright/src/page/index.ts

@@ -17,6 +17,7 @@ import {
 	setClipboardData,
 	pressKeyWithModifier,
 } from './press-key-with-modifier';
+import { pressKeyTimes } from './press-key-times';
 import { openPreviewPage } from './preview';
 import { setBrowserViewport } from './set-browser-viewport';
 import { showBlockToolbar } from './show-block-toolbar';
@@ -48,6 +49,7 @@ class PageUtils {
 	openDocumentSettingsSidebar = openDocumentSettingsSidebar;
 	openPreviewPage = openPreviewPage;
 	setBrowserViewport = setBrowserViewport;
+	pressKeyTimes = pressKeyTimes;
 }
 
 export { PageUtils };

packages/e2e-test-utils-playwright/src/page/press-key-times.js

@@ -0,0 +1,11 @@
+/**
+ * Presses the given keyboard key a number of times in sequence.
+ *
+ * @param {string} key   Key to press.
+ * @param {number} count Number of times to press.
+ */
+export async function pressKeyTimes( key, count ) {
+	while ( count-- ) {
+		await this.page.keyboard.press( key );
+	}
+}