Merge pull request #8466 from ckeditor/i/7892

Fix (engine): Editor should not crash while selecting an Image from bottom to top. Closes #7892.

packages/ckeditor5-engine/src/model/utils/selection-post-fixer.js

@@ -268,7 +268,10 @@ function mergeIntersectingRanges( ranges ) {
 	for ( const range of ranges ) {
 		const previousRange = nonIntersectingRanges.pop();
 
-		if ( range.isIntersecting( previousRange ) ) {
+		if ( range.isEqual( previousRange ) ) {
+			// Use only one of two identical ranges.
+			nonIntersectingRanges.push( previousRange );
+		} else if ( range.isIntersecting( previousRange ) ) {
 			// Get the sum of two ranges.
 			const start = previousRange.start.isAfter( range.start ) ? range.start : previousRange.start;
 			const end = previousRange.end.isAfter( range.end ) ? previousRange.end : range.end;

packages/ckeditor5-engine/tests/manual/tickets/7892/1.html

@@ -0,0 +1,7 @@
+<div id="editor">
+	<p>Finish the selection HERE.</p>
+	<figure class="image">
+		<img src="sample.jpg" alt="sample image" />
+	</figure>
+	<p>Start the selection HERE.</p>
+</div>

packages/ckeditor5-engine/tests/manual/tickets/7892/1.js

@@ -0,0 +1,25 @@
+/**
+ * @license Copyright (c) 2003-2020, CKSource - Frederico Knabben. All rights reserved.
+ * For licensing, see LICENSE.md or https://ckeditor.com/legal/ckeditor-oss-license
+ */
+
+/* globals window, document, console */
+
+import ClassicEditor from '@ckeditor/ckeditor5-editor-classic/src/classiceditor';
+import ArticlePluginSet from '@ckeditor/ckeditor5-core/tests/_utils/articlepluginset';
+
+const config = {
+	plugins: [ ArticlePluginSet ],
+	toolbar: [
+		'heading', '|', 'bold', 'italic', 'link', 'bulletedList', 'numberedList', 'blockQuote', 'undo', 'redo'
+	]
+};
+
+ClassicEditor
+	.create( document.querySelector( '#editor' ), config )
+	.then( editor => {
+		window.editor = editor;
+	} )
+	.catch( error => {
+		console.error( error.stack );
+	} );

packages/ckeditor5-engine/tests/manual/tickets/7892/1.md

@@ -0,0 +1,9 @@
+### Selecting an Image from bottom to top throws exceptions [#7892](https://github.com/ckeditor/ckeditor5/issues/7892)
+
+1. Open Firefox.
+2. Start the selection below the image using mouse.
+3. Finish the selection above the image.
+
+**Expected result**: there is no error in the console.
+
+**Unexpected result**: there is an `Uncaught CKEditorError: model-selection-range-intersects: Trying to add a range that intersects with another range in the selection` error in the console.

packages/ckeditor5-engine/tests/model/utils/selection-post-fixer.js

@@ -1038,6 +1038,35 @@ describe( 'Selection post-fixer', () => {
 					'[<figure></figure>]'
 				);
 			} );
+
+			it( 'should fix multi-range selection with equal ranges', () => {
+				// It may happen that multi-range selection contains equal ranges.
+				// Duplicated ranges should be ommited from the final (merged) selection.
+				// https://github.com/ckeditor/ckeditor5/issues/7892
+				model.change( writer => {
+					const firstRange = writer.createRange(
+						writer.createPositionAt( modelRoot.getChild( 1 ).getChild( 0 ), 3 )
+					);
+
+					const duplicatedRange = firstRange.clone();
+
+					const otherRange = writer.createRange(
+						writer.createPositionAt( modelRoot.getChild( 1 ).getChild( 0 ), 3 ),
+						writer.createPositionAt( modelRoot.getChild( 2 ), 0 )
+					);
+
+					// <paragraph>foo</paragraph><image><caption>xxx[][][</caption></image><paragraph>]bar</paragraph>
+					writer.setSelection( [ firstRange, duplicatedRange, otherRange ] );
+				} );
+
+				expect( getModelData( model ) ).to.equal(
+					'<paragraph>foo</paragraph>' +
+					'[<image>' +
+						'<caption>xxx</caption>' +
+					'</image>' +
+					'<paragraph>]bar</paragraph>'
+				);
+			} );
 		} );
 
 		describe( 'non-collapsed selection - other scenarios', () => {