T/404: Better handling of   block filler.

src/dataprocessor/htmldataprocessor.js

@@ -11,7 +11,6 @@
 
 import BasicHtmlWriter from './basichtmlwriter';
 import DomConverter from '../view/domconverter';
-import { NBSP_FILLER } from '../view/filler';
 
 /**
  * The HTML data processor class.
@@ -38,7 +37,7 @@ export default class HtmlDataProcessor {
 		 * @private
 		 * @member {module:engine/view/domconverter~DomConverter}
 		 */
-		this._domConverter = new DomConverter( { blockFiller: NBSP_FILLER } );
+		this._domConverter = new DomConverter( { blockFillerMode: 'nbsp' } );
 
 		/**
 		 * A basic HTML writer instance used to convert DOM elements to an HTML string.

src/dataprocessor/xmldataprocessor.js

@@ -11,7 +11,6 @@
 
 import BasicHtmlWriter from './basichtmlwriter';
 import DomConverter from '../view/domconverter';
-import { NBSP_FILLER } from '../view/filler';
 
 /**
  * The XML data processor class.
@@ -54,7 +53,7 @@ export default class XmlDataProcessor {
 		 * @private
 		 * @member {module:engine/view/domconverter~DomConverter}
 		 */
-		this._domConverter = new DomConverter( { blockFiller: NBSP_FILLER } );
+		this._domConverter = new DomConverter( { blockFillerMode: 'nbsp' } );
 
 		/**
 		 * A basic HTML writer instance used to convert DOM elements to an XML string.

src/view/domconverter.js

@@ -16,7 +16,15 @@ import ViewRange from './range';
 import ViewSelection from './selection';
 import ViewDocumentFragment from './documentfragment';
 import ViewTreeWalker from './treewalker';
-import { BR_FILLER, INLINE_FILLER_LENGTH, isBlockFiller, isInlineFiller, startsWithFiller, getDataWithoutFiller } from './filler';
+import {
+	BR_FILLER,
+	NBSP_FILLER,
+	INLINE_FILLER_LENGTH,
+	isBlockFiller,
+	isInlineFiller,
+	startsWithFiller,
+	getDataWithoutFiller
+} from './filler';
 
 import global from '@ckeditor/ckeditor5-utils/src/dom/global';
 import indexOf from '@ckeditor/ckeditor5-utils/src/dom/indexof';
@@ -42,7 +50,7 @@ export default class DomConverter {
 	 * Creates DOM converter.
 	 *
 	 * @param {Object} options Object with configuration options.
-	 * @param {Function} [options.blockFiller=module:engine/view/filler~BR_FILLER] Block filler creator.
+	 * @param {module:engine/view/filler~BlockFillerMode} [options.blockFillerMode='br'] Type of a block filler w
 	 */
 	constructor( options = {} ) {
 		// Using WeakMap prevent memory leaks: when the converter will be destroyed all referenced between View and DOM
@@ -56,13 +64,12 @@ export default class DomConverter {
 		// I've been here. Seen stuff. Afraid of code now.
 
 		/**
-		 * Block {@link module:engine/view/filler filler} creator, which is used to create all block fillers during the
-		 * view to DOM conversion and to recognize block fillers during the DOM to view conversion.
+		 * The mode of a block filler used by DOM converter.
 		 *
 		 * @readonly
-		 * @member {Function} module:engine/view/domconverter~DomConverter#blockFiller
+		 * @member {String} module:engine/view/domconverter~DomConverter#blockFillerMode
 		 */
-		this.blockFiller = options.blockFiller || BR_FILLER;
+		this.blockFillerMode = options.blockFillerMode || 'br';
 
 		/**
 		 * Tag names of DOM `Element`s which are considered pre-formatted elements.
@@ -80,6 +87,16 @@ export default class DomConverter {
 		 */
 		this.blockElements = [ 'p', 'div', 'h1', 'h2', 'h3', 'h4', 'h5', 'h6' ];
 
+		/**
+		 * Block {@link module:engine/view/filler filler} creator, which is used to create all block fillers during the
+		 * view to DOM conversion and to recognize block fillers during the DOM to view conversion.
+		 *
+		 * @readonly
+		 * @private
+		 * @member {Function} module:engine/view/domconverter~DomConverter#_blockFiller
+		 */
+		this._blockFiller = this.blockFillerMode == 'br' ? BR_FILLER : NBSP_FILLER;
+
 		/**
 		 * DOM to View mapping.
 		 *
@@ -254,7 +271,7 @@ export default class DomConverter {
 
 		for ( const childView of viewElement.getChildren() ) {
 			if ( fillerPositionOffset === offset ) {
-				yield this.blockFiller( domDocument );
+				yield this._blockFiller( domDocument );
 			}
 
 			yield this.viewToDom( childView, domDocument, options );
@@ -263,7 +280,7 @@ export default class DomConverter {
 		}
 
 		if ( fillerPositionOffset === offset ) {
-			yield this.blockFiller( domDocument );
+			yield this._blockFiller( domDocument );
 		}
 	}
 
@@ -370,7 +387,7 @@ export default class DomConverter {
 	 * or `null` if DOM node is a {@link module:engine/view/filler filler} or the given node is an empty text node.
 	 */
 	domToView( domNode, options = {} ) {
-		if ( isBlockFiller( domNode, this.blockFiller ) ) {
+		if ( isBlockFiller( domNode, this.blockFillerMode ) ) {
 			return null;
 		}
 
@@ -528,7 +545,7 @@ export default class DomConverter {
 	 * @returns {module:engine/view/position~Position} viewPosition View position.
 	 */
 	domPositionToView( domParent, domOffset ) {
-		if ( isBlockFiller( domParent, this.blockFiller ) ) {
+		if ( isBlockFiller( domParent, this.blockFillerMode ) ) {
 			return this.domPositionToView( domParent.parentNode, indexOf( domParent ) );
 		}
 

src/view/filler.js

@@ -50,6 +50,9 @@ export const BR_FILLER = domDocument => {
 	return fillerBr;
 };
 
+// eslint-disable-next-line new-cap
+const BR_FILLER_REF = BR_FILLER( window.document );
+
 /**
  * Non-breaking space filler creator. This is a function which creates ` ` text node.
  * It defines how the filler is created.
@@ -65,13 +68,17 @@ export const NBSP_FILLER = domDocument => domDocument.createTextNode( '\u00A0' )
 export const INLINE_FILLER_LENGTH = 7;
 
 /**
- * Inline filler which is sequence of the zero width spaces.
+ * Inline filler which is a sequence of the zero width spaces.
  */
-export let INLINE_FILLER = '';
+export const INLINE_FILLER = ( () => {
+	let inlineFiller = '';
 
-for ( let i = 0; i < INLINE_FILLER_LENGTH; i++ ) {
-	INLINE_FILLER += '\u200b';
-}
+	for ( let i = 0; i < INLINE_FILLER_LENGTH; i++ ) {
+		inlineFiller += '\u200b';
+	}
+
+	return inlineFiller;
+} )(); // Usu IIF so the INLINE_FILLER appears as a constant in the docs.
 
 /**
  * Checks if the node is a text node which starts with the {@link module:engine/view/filler~INLINE_FILLER inline filler}.
@@ -119,28 +126,21 @@ export function getDataWithoutFiller( domText ) {
 	}
 }
 
-// Cache block fillers templates to improve performance.
-const templateBlockFillers = new WeakMap();
-
 /**
  * Checks if the node is an instance of the block filler of the given type.
  *
  *		const brFillerInstance = BR_FILLER( document );
- *		isBlockFiller( brFillerInstance, BR_FILLER ); // true
+ *		isBlockFiller( brFillerInstance, 'br' ); // true
+ *		isBlockFiller( brFillerInstance, 'nbsp' ); // false
+ *
+ * **Note:**: For the `'nbsp'` mode the method also checks context of a node so it cannot be a detached node.
  *
  * @param {Node} domNode DOM node to check.
- * @param {Function} blockFiller Block filler creator.
- * @returns {Boolean} True if text node contains only {@link module:engine/view/filler~INLINE_FILLER inline filler}.
+ * @param {module:engine/view/filler~BlockFillerMode} mode Mode of a block filler.
+ * @returns {Boolean} True if a node is considered a block filler for given mode.
  */
-export function isBlockFiller( domNode, blockFiller ) {
-	let templateBlockFiller = templateBlockFillers.get( blockFiller );
-
-	if ( !templateBlockFiller ) {
-		templateBlockFiller = blockFiller( window.document );
-		templateBlockFillers.set( blockFiller, templateBlockFiller );
-	}
-
-	return domNode.isEqualNode( templateBlockFiller );
+export function isBlockFiller( domNode, mode ) {
+	return mode == 'br' ? domNode.isEqualNode( BR_FILLER_REF ) : isNbspBlockFiller( domNode );
 }
 
 /**
@@ -168,3 +168,39 @@ function jumpOverInlineFiller( evt, data ) {
 		}
 	}
 }
+
+// Checks if given node is a nbsp block filler.
+//
+// A &nbsp; is a block filler only if it is a single child of a block element.
+//
+// @param {Node} domNode DOM node.
+// @returns {Boolean}
+function isNbspBlockFiller( domNode ) {
+	const isNBSP = isText( domNode ) && domNode.data == '\u00A0';
+
+	return isNBSP && hasBlockParent( domNode ) && domNode.parentNode.childNodes.length === 1;
+}
+
+// Name of DOM nodes that are considered a block.
+const blockElements = [ 'p', 'div', 'h1', 'h2', 'h3', 'h4', 'h5', 'h6' ];
+
+// Checks if domNode has block parent.
+//
+// @param {Node} domNode DOM node.
+// @returns {Boolean}
+function hasBlockParent( domNode ) {
+	const parent = domNode.parentNode;
+
+	return parent && parent.tagName && blockElements.includes( parent.tagName.toLowerCase() );
+}
+
+/**
+ * Enum representing type of the block filler.
+ *
+ * Possible values:
+ *
+ * * `br` - for `<br>` block filler used in editing view,
+ * * `nbsp` - for `&nbsp;` block fillers used in the data.
+ *
+ * @typedef {String} module:engine/view/filler~BlockFillerMode
+ */

src/view/renderer.js

@@ -590,7 +590,7 @@ export default class Renderer {
 	_diffNodeLists( actualDomChildren, expectedDomChildren ) {
 		actualDomChildren = filterOutFakeSelectionContainer( actualDomChildren, this._fakeSelectionContainer );
 
-		return diff( actualDomChildren, expectedDomChildren, sameNodes.bind( null, this.domConverter.blockFiller ) );
+		return diff( actualDomChildren, expectedDomChildren, sameNodes.bind( null, this.domConverter.blockFillerMode ) );
 	}
 
 	/**
@@ -922,11 +922,11 @@ function areSimilar( node1, node2 ) {
 //		* Two block filler elements.
 //
 // @private
-// @param {Function} blockFiller Block filler creator function, see {@link module:engine/view/domconverter~DomConverter#blockFiller}.
+// @param {String} blockFillerMode Block filler mode, see {@link module:engine/view/domconverter~DomConverter#blockFillerMode}.
 // @param {Node} node1
 // @param {Node} node2
 // @returns {Boolean}
-function sameNodes( blockFiller, actualDomChild, expectedDomChild ) {
+function sameNodes( blockFillerMode, actualDomChild, expectedDomChild ) {
 	// Elements.
 	if ( actualDomChild === expectedDomChild ) {
 		return true;
@@ -936,8 +936,8 @@ function sameNodes( blockFiller, actualDomChild, expectedDomChild ) {
 		return actualDomChild.data === expectedDomChild.data;
 	}
 	// Block fillers.
-	else if ( isBlockFiller( actualDomChild, blockFiller ) &&
-		isBlockFiller( expectedDomChild, blockFiller ) ) {
+	else if ( isBlockFiller( actualDomChild, blockFillerMode ) &&
+		isBlockFiller( expectedDomChild, blockFillerMode ) ) {
 		return true;
 	}
 

tests/dataprocessor/htmldataprocessor.js

@@ -59,33 +59,32 @@ describe( 'HtmlDataProcessor', () => {
 			} );
 		}
 
-		// Uncomment this test after fixing #404.
-		// describe( 'https://github.com/ckeditor/ckeditor5-clipboard/issues/2#issuecomment-310417731 + #404', () => {
-		// 	it( 'does not lose whitespaces in Chrome\'s paste-like content', () => {
-		// 		const fragment = dataProcessor.toView(
-		// 			'<meta charset=\'utf-8\'>' +
-		// 			'<span>This is the<span>\u00a0</span></span>' +
-		// 			'<a href="url">third developer preview</a>' +
-		// 			'<span><span>\u00a0</span>of<span>\u00a0</span></span>' +
-		// 			'<strong>CKEditor\u00a05</strong>' +
-		// 			'<span>.</span>'
-		// 		);
-
-		// 		expect( stringify( fragment ) ).to.equal(
-		// 			'<span>This is the<span>\u00a0</span></span>' +
-		// 			'<a href="url">third developer preview</a>' +
-		// 			'<span><span>\u00a0</span>of<span>\u00a0</span></span>' +
-		// 			'<strong>CKEditor\u00a05</strong>' +
-		// 			'<span>.</span>'
-		// 		);
-
-		// 		// Just to be sure... stringify() uses conversion and the browser extensively,
-		// 		// so it's not entirely safe.
-		// 		expect( fragment.getChild( 0 ).getChild( 1 ).getChild( 0 ).data ).to.equal( '\u00a0' );
-		// 		expect( fragment.getChild( 2 ).getChild( 0 ).getChild( 0 ).data ).to.equal( '\u00a0' );
-		// 		expect( fragment.getChild( 2 ).getChild( 2 ).getChild( 0 ).data ).to.equal( '\u00a0' );
-		// 	} );
-		// } );
+		describe( 'https://github.com/ckeditor/ckeditor5-clipboard/issues/2#issuecomment-310417731 + #404', () => {
+			it( 'does not lose whitespaces in Chrome\'s paste-like content', () => {
+				const fragment = dataProcessor.toView(
+					'<meta charset=\'utf-8\'>' +
+					'<span>This is the<span>\u00a0</span></span>' +
+					'<a href="url">third developer preview</a>' +
+					'<span><span>\u00a0</span>of<span>\u00a0</span></span>' +
+					'<strong>CKEditor\u00a05</strong>' +
+					'<span>.</span>'
+				);
+
+				expect( stringify( fragment ) ).to.equal(
+					'<span>This is the<span>\u00a0</span></span>' +
+					'<a href="url">third developer preview</a>' +
+					'<span><span>\u00a0</span>of<span>\u00a0</span></span>' +
+					'<strong>CKEditor\u00a05</strong>' +
+					'<span>.</span>'
+				);
+
+				// Just to be sure... stringify() uses conversion and the browser extensively,
+				// so it's not entirely safe.
+				expect( fragment.getChild( 0 ).getChild( 1 ).getChild( 0 ).data ).to.equal( '\u00a0' );
+				expect( fragment.getChild( 2 ).getChild( 0 ).getChild( 0 ).data ).to.equal( '\u00a0' );
+				expect( fragment.getChild( 2 ).getChild( 2 ).getChild( 0 ).data ).to.equal( '\u00a0' );
+			} );
+		} );
 	} );
 
 	describe( 'toData()', () => {

tests/view/domconverter/dom-to-view.js

@@ -9,7 +9,7 @@ import ViewElement from '../../../src/view/element';
 import ViewDocumentSelection from '../../../src/view/documentselection';
 import DomConverter from '../../../src/view/domconverter';
 import ViewDocumentFragment from '../../../src/view/documentfragment';
-import { INLINE_FILLER, INLINE_FILLER_LENGTH, NBSP_FILLER } from '../../../src/view/filler';
+import { INLINE_FILLER, INLINE_FILLER_LENGTH, NBSP_FILLER, BR_FILLER } from '../../../src/view/filler';
 
 import { parse, stringify } from '../../../src/dev-utils/view';
 
@@ -157,7 +157,8 @@ describe( 'DomConverter', () => {
 		} );
 
 		it( 'should return null for block filler', () => {
-			const domFiller = converter.blockFiller( document );
+			// eslint-disable-next-line new-cap
+			const domFiller = BR_FILLER( document );
 
 			expect( converter.domToView( domFiller ) ).to.be.null;
 		} );
@@ -682,7 +683,8 @@ describe( 'DomConverter', () => {
 		} );
 
 		it( 'should skip filler', () => {
-			const domFiller = converter.blockFiller( document );
+			// eslint-disable-next-line new-cap
+			const domFiller = BR_FILLER( document );
 			const domP = createElement( document, 'p', null, domFiller );
 
 			const viewChildren = Array.from( converter.domChildrenToView( domP ) );
@@ -761,7 +763,7 @@ describe( 'DomConverter', () => {
 		} );
 
 		it( 'should converter position inside block filler', () => {
-			const converter = new DomConverter( { blockFiller: NBSP_FILLER } );
+			const converter = new DomConverter( { blockFillerMode: 'nbsp' } );
 			const domFiller = NBSP_FILLER( document ); // eslint-disable-line new-cap
 			const domP = createElement( document, 'p', null, domFiller );
 

tests/view/domconverter/domconverter.js

@@ -10,7 +10,7 @@ import ViewEditable from '../../../src/view/editableelement';
 import ViewDocument from '../../../src/view/document';
 import ViewUIElement from '../../../src/view/uielement';
 import ViewContainerElement from '../../../src/view/containerelement';
-import { BR_FILLER, NBSP_FILLER, INLINE_FILLER, INLINE_FILLER_LENGTH } from '../../../src/view/filler';
+import { INLINE_FILLER, INLINE_FILLER_LENGTH } from '../../../src/view/filler';
 import testUtils from '@ckeditor/ckeditor5-core/tests/_utils/utils';
 import global from '@ckeditor/ckeditor5-utils/src/dom/global';
 
@@ -24,13 +24,13 @@ describe( 'DomConverter', () => {
 	} );
 
 	describe( 'constructor()', () => {
-		it( 'should create converter with BR block filler by default', () => {
-			expect( converter.blockFiller ).to.equal( BR_FILLER );
+		it( 'should create converter with BR block filler mode by default', () => {
+			expect( converter.blockFillerMode ).to.equal( 'br' );
 		} );
 
-		it( 'should create converter with defined block filler', () => {
-			converter = new DomConverter( { blockFiller: NBSP_FILLER } );
-			expect( converter.blockFiller ).to.equal( NBSP_FILLER );
+		it( 'should create converter with defined block mode filler', () => {
+			converter = new DomConverter( { blockFillerMode: 'nbsp' } );
+			expect( converter.blockFillerMode ).to.equal( 'nbsp' );
 		} );
 	} );