fix(super-editor): guard against style definition nodes without elements (#2379)

Author: luccas-harbour

packages/super-editor/src/core/super-converter/docx-helpers/get-default-style-definition.js

@@ -24,6 +24,8 @@ export const getDefaultStyleDefinition = (defaultStyleId, docx) => {
   const firstMatch = elementsWithId[0];
   if (!firstMatch) return result;
 
+  if (!firstMatch.elements) return result;
+
   const qFormat = elementsWithId.find((el) => {
     const qFormat = el.elements.find((innerEl) => innerEl.name === 'w:qFormat');
     return qFormat;

packages/super-editor/src/core/super-converter/docx-helpers/get-default-style-definition.test.js

@@ -38,6 +38,28 @@ describe('getDefaultStyleDefinition', () => {
     expect(res).toEqual({ lineSpaceBefore: null, lineSpaceAfter: null });
   });
 
+  it('returns minimal object when matching style has no elements', () => {
+    const docx = {
+      'word/styles.xml': {
+        elements: [
+          {
+            elements: [
+              {
+                name: 'w:style',
+                attributes: { 'w:styleId': 'Heading1' },
+              },
+            ],
+          },
+        ],
+      },
+    };
+
+    const res = getDefaultStyleDefinition('Heading1', docx);
+
+    expect(res).toEqual({ lineSpaceBefore: null, lineSpaceAfter: null });
+    expect(parseMarks).not.toHaveBeenCalled();
+  });
+
   it('parses style definition with spacing, indent, flags, and marks', () => {
     const docx = {
       'word/styles.xml': {