HtmlEditor: Fix type error when parsing list with non-string Delta insert (T1292587) (#30105)

Co-authored-by: Ruslan Farkhutdinov <[email protected]>

Author: r-farkhutdinov

packages/devextreme/js/__internal/ui/html_editor/matchers/m_wordLists.ts

@@ -1,3 +1,5 @@
+import { isString } from '@js/core/utils/type';
+
 function getListType(matches) {
   const prefix = matches[1];
   return prefix.match(/\S+\./) ? 'ordered' : 'bullet';
@@ -29,6 +31,11 @@ const getMatcher = (quill) => {
     const ops = delta.ops.slice();
 
     const insertOperation = ops[0];
+
+    if (!isString(insertOperation.insert)) {
+      return delta;
+    }
+
     insertOperation.insert = insertOperation.insert.replace(/^\s+/, '');
     const listDecoratorMatches = insertOperation.insert.match(/^(\S+)\s+/);
     const indent = listDecoratorMatches && getIndent(node, msStyleAttributeName);

packages/devextreme/testing/tests/DevExpress.ui.widgets.htmlEditor/htmlEditorParts/multilineIntegration.tests.js

@@ -65,6 +65,33 @@ export default function() {
                 assert.strictEqual(instance.option('value'), prepareTableValue(value));
                 assert.strictEqual(markup, value);
             });
+
+            ['MsoListParagraphCxSpFirst', 'MsoListParagraphCxSpMiddle', 'MsoListParagraphCxSpLast'].forEach(className => {
+                test(`editor should not throw error for ${className} class with allowSoftLineBreak (T1292587)`, function(assert) {
+                    const spy = sinon.spy(console, 'error');
+                    const value = `<p class="${className}"><br><br></p>`;
+
+                    try {
+                        $('#htmlEditor').dxHtmlEditor({ value }).dxHtmlEditor('instance');
+
+                        assert.strictEqual(spy.called, false, 'No console error was thrown');
+                    } finally {
+                        spy.restore();
+                    }
+                });
+
+                test(`editor should preserve double <br> in list paragraph for ${className} class (T1292587)`, function(assert) {
+                    const value = `<p class="${className}"><br><br></p>`;
+                    const htmlEditor = $('#htmlEditor').dxHtmlEditor({
+                        value
+                    }).dxHtmlEditor('instance');
+
+                    const markup = htmlEditor.option('value');
+                    const $markup = $('<div>').html(markup);
+
+                    assert.strictEqual($markup.find('br').length, 2, 'Two soft breaks preserved');
+                });
+            });
         });
 
         testModule('runtime editing', moduleConfig, function() {