Allow to disable new line padding on paste for specific elements

packages/ckeditor5-clipboard/src/clipboardpipeline.ts

@@ -323,7 +323,7 @@ export default class ClipboardPipeline extends Plugin {
 		this.listenTo<ViewDocumentClipboardOutputEvent>( viewDocument, 'clipboardOutput', ( evt, data ) => {
 			if ( !data.content.isEmpty ) {
 				data.dataTransfer.setData( 'text/html', this.editor.data.htmlProcessor.toData( data.content ) );
-				data.dataTransfer.setData( 'text/plain', viewToPlainText( data.content ) );
+				data.dataTransfer.setData( 'text/plain', viewToPlainText( editor.data.htmlProcessor.domConverter, data.content ) );
 			}
 
 			if ( data.method == 'cut' ) {

packages/ckeditor5-clipboard/src/utils/viewtoplaintext.ts

@@ -7,7 +7,7 @@
  * @module clipboard/utils/viewtoplaintext
  */
 
-import type { ViewDocumentFragment, ViewElement, ViewItem } from '@ckeditor/ckeditor5-engine';
+import type { DomConverter, ViewDocumentFragment, ViewElement, ViewItem } from '@ckeditor/ckeditor5-engine';
 
 // Elements which should not have empty-line padding.
 // Most `view.ContainerElement` want to be separate by new-line, but some are creating one structure
@@ -19,10 +19,14 @@ const listElements = [ 'ol', 'ul' ];
 /**
  * Converts {@link module:engine/view/item~Item view item} and all of its children to plain text.
  *
+ * @param converter The converter instance.
  * @param viewItem View item to convert.
  * @returns Plain text representation of `viewItem`.
  */
-export default function viewToPlainText( viewItem: ViewItem | ViewDocumentFragment ): string {
+export default function viewToPlainText(
+	converter: DomConverter,
+	viewItem: ViewItem | ViewDocumentFragment
+): string {
 	if ( viewItem.is( '$text' ) || viewItem.is( '$textProxy' ) ) {
 		return viewItem.data;
 	}
@@ -44,7 +48,7 @@ export default function viewToPlainText( viewItem: ViewItem | ViewDocumentFragme
 	let prev: ViewElement | null = null;
 
 	for ( const child of ( viewItem as ViewElement | ViewDocumentFragment ).getChildren() ) {
-		text += newLinePadding( child as ViewElement, prev ) + viewToPlainText( child );
+		text += newLinePadding( converter, child as ViewElement, prev ) + viewToPlainText( converter, child );
 		prev = child as ViewElement;
 	}
 
@@ -55,6 +59,7 @@ export default function viewToPlainText( viewItem: ViewItem | ViewDocumentFragme
  * Returns new line padding to prefix the given elements with.
  */
 function newLinePadding(
+	converter: DomConverter,
 	element: ViewElement,
 	previous: ViewElement | null
 ): string {
@@ -94,6 +99,11 @@ function newLinePadding(
 		return '';
 	}
 
+	if ( !converter.isBlockViewElement( previous ) && !converter.isBlockViewElement( element ) ) {
+		// Don't add padding between non-block elements.
+		return '';
+	}
+
 	// Add empty lines between container elements.
 	return '\n\n';
 }

packages/ckeditor5-clipboard/tests/utils/viewtoplaintext.js

@@ -3,14 +3,26 @@
  * For licensing, see LICENSE.md or https://ckeditor.com/legal/ckeditor-oss-license
  */
 
+import { DomConverter, StylesProcessor, ViewDocument } from '@ckeditor/ckeditor5-engine';
 import viewToPlainText from '../../src/utils/viewtoplaintext.js';
 
 import { parse as parseView } from '@ckeditor/ckeditor5-engine/src/dev-utils/view.js';
 
 describe( 'viewToPlainText()', () => {
+	let converter, viewDocument;
+
+	beforeEach( () => {
+		viewDocument = new ViewDocument( new StylesProcessor() );
+		converter = new DomConverter( viewDocument );
+	} );
+
+	afterEach( () => {
+		viewDocument.destroy();
+	} );
+
 	function testViewToPlainText( viewString, expectedText ) {
 		const view = parseView( viewString );
-		const text = viewToPlainText( view );
+		const text = viewToPlainText( converter, view );
 
 		expect( text ).to.equal( expectedText );
 	}
@@ -34,14 +46,21 @@ describe( 'viewToPlainText()', () => {
 		);
 	} );
 
+	it( 'should not put empty line between inline container elements', () => {
+		testViewToPlainText(
+			'<container:strong>Foo</container:strong><container:strong>Bar</container:strong>',
+			'FooBar'
+		);
+	} );
+
 	it( 'should not put empty line before or after the element with `dataPipeline:transparentRendering` property', () => {
 		const viewString = 'Abc <container:h1>Header</container:h1> xyz';
 		const expectedText = 'Abc Header xyz';
 
 		const view = parseView( viewString );
 		view.getChild( 1 )._setCustomProperty( 'dataPipeline:transparentRendering', true );
 
-		const text = viewToPlainText( view );
+		const text = viewToPlainText( converter, view );
 
 		expect( text ).to.equal( expectedText );
 	} );

packages/ckeditor5-engine/src/view/domconverter.ts

@@ -766,7 +766,7 @@ export default class DomConverter {
 
 			if ( viewChild !== null ) {
 				// Whitespace cleaning before entering a block element (between block elements).
-				if ( this._isBlockViewElement( viewChild ) ) {
+				if ( this.isBlockViewElement( viewChild ) ) {
 					this._processDomInlineNodes( domElement, inlineNodes, options );
 				}
 
@@ -1162,6 +1162,13 @@ export default class DomConverter {
 		return node && node.nodeType == Node.DOCUMENT_FRAGMENT_NODE;
 	}
 
+	/**
+	 * Returns `true` if a view node belongs to {@link #blockElements}. `false` otherwise.
+	 */
+	public isBlockViewElement( node: ViewNode ): boolean {
+		return node.is( 'element' ) && this.blockElements.includes( node.name );
+	}
+
 	/**
 	 * Checks if the node is an instance of the block filler for this DOM converter.
 	 *
@@ -1443,7 +1450,7 @@ export default class DomConverter {
 				if ( this._isViewElementWithRawContent( viewElement, options ) ) {
 					viewElement._setCustomProperty( '$rawContent', ( domNode as DomElement ).innerHTML );
 
-					if ( !this._isBlockViewElement( viewElement ) ) {
+					if ( !this.isBlockViewElement( viewElement ) ) {
 						inlineNodes.push( viewElement );
 					}
 
@@ -1743,13 +1750,6 @@ export default class DomConverter {
 		return this.isElement( node ) && this.blockElements.includes( node.tagName.toLowerCase() );
 	}
 
-	/**
-	 * Returns `true` if a view node belongs to {@link #blockElements}. `false` otherwise.
-	 */
-	private _isBlockViewElement( node: ViewNode ): boolean {
-		return node.is( 'element' ) && this.blockElements.includes( node.name );
-	}
-
 	/**
 	 * Returns `true` if a DOM node belongs to {@link #inlineObjectElements}. `false` otherwise.
 	 */

packages/ckeditor5-engine/tests/view/domconverter/domconverter.js

@@ -18,6 +18,7 @@ import { StylesProcessor } from '../../../src/view/stylesmap.js';
 import ViewPosition from '../../../src/view/position.js';
 import ViewRange from '../../../src/view/range.js';
 import { ViewText } from '@ckeditor/ckeditor5-engine';
+import { parse as parseView } from '@ckeditor/ckeditor5-engine/src/dev-utils/view.js';
 
 describe( 'DomConverter', () => {
 	let converter, viewDocument;
@@ -425,6 +426,33 @@ describe( 'DomConverter', () => {
 		} );
 	} );
 
+	describe( 'isBlockViewElement()', () => {
+		const blockElements = [
+			'address', 'article', 'aside', 'blockquote', 'caption', 'center', 'dd', 'details', 'dir', 'div',
+			'dl', 'dt', 'fieldset', 'figcaption', 'figure', 'footer', 'form', 'h1', 'h2', 'h3', 'h4', 'h5', 'h6', 'header',
+			'hgroup', 'legend', 'li', 'main', 'menu', 'nav', 'ol', 'p', 'pre', 'section', 'summary', 'table', 'tbody',
+			'td', 'tfoot', 'th', 'thead', 'tr', 'ul'
+		];
+
+		const inlineElements = [ 'span', 'i', 'b', 'strong', 'a' ];
+
+		for ( const elementName of blockElements ) {
+			it( `should return true for <${ elementName }>`, () => {
+				const view = parseView( `<${ elementName }></${ elementName }>` );
+
+				expect( converter.isBlockViewElement( view ) ).to.be.true;
+			} );
+		}
+
+		for ( const elementName of inlineElements ) {
+			it( `should return false for <${ elementName }>`, () => {
+				const view = parseView( `<${ elementName }></${ elementName }>` );
+
+				expect( converter.isBlockViewElement( view ) ).to.be.false;
+			} );
+		}
+	} );
+
 	describe( 'shouldRenderAttribute()', () => {
 		it( 'should allow all in data pipeline', () => {
 			expect( converter.shouldRenderAttribute( 'onclick', 'anything' ) ).to.be.false;