fix: markdown inconsistency with bold and italics (#33157)

.changeset/sweet-nails-grin.md

+---
+"@rocket.chat/meteor": patch
+---
+
+Fixed inconsistency between the markdown parser from the composer and the rest of the application when using bold and italics in a text.

apps/meteor/client/components/MarkdownText.spec.tsx

+import { mockAppRoot } from '@rocket.chat/mock-providers';
+import { render } from '@testing-library/react';
+import React from 'react';
+
+import MarkdownText from './MarkdownText';
+
+import '@testing-library/jest-dom';
+
+const normalizeHtml = (html: any) => {
+	return html.replace(/\s+/g, ' ').trim();
+};
+
+const markdownText = `
+  # Heading 1
+  **Paragraph text**: *Bold with one asterisk* **Bold with two asterisks** Lorem ipsum dolor sit amet, consectetur adipiscing elit.
+  ## Heading 2
+  _Italic Text_: _Italic with one underscore_ __Italic with two underscores__ Lorem ipsum dolor sit amet, consectetur adipiscing elit.
+  ### Heading 3 
+  Lists, Links and elements
+  **Unordered List** 
+  - List Item 1 
+  - List Item 2 
+  - List Item 3 
+  - List Item 4
+  **Ordered List** 
+  1. List Item 1
+  2. List Item 2
+  3. List Item 3
+  4. List Item 4
+  **Links:** 
+  [Rocket.Chat](rocket.chat)
+  gabriel.engel@rocket.chat 
+  +55991999999 
+  \`Inline code\`
+  \`\`\`typescript 
+  const test = 'this is code'
+  \`\`\`
+`;
+
+it('should render html elements as expected using default parser', async () => {
+	const { container } = render(<MarkdownText content={markdownText} variant='document' />, {
+		wrapper: mockAppRoot().build(),
+		legacyRoot: true,
+	});
+
+	const normalizedHtml = normalizeHtml(container.innerHTML);
+
+	expect(normalizedHtml).toContain('<h1>Heading 1</h1>');
+	expect(normalizedHtml).toContain(
+		'<strong>Paragraph text</strong>: <strong>Bold with one asterisk</strong> <strong>Bold with two asterisks</strong> Lorem ipsum dolor sit amet',
+	);
+	expect(normalizedHtml).toContain('<h2>Heading 2</h2>');
+	expect(normalizedHtml).toContain(
+		'<em>Italic Text</em>: <em>Italic with one underscore</em> <em>Italic with two underscores</em> Lorem ipsum dolor sit amet',
+	);
+	expect(normalizedHtml).toContain('<h3>Heading 3</h3>');
+	expect(normalizedHtml).toContain('<ul> <li>List Item 1 </li><li>List Item 2 </li><li>List Item 3 </li><li>List Item 4');
+	expect(normalizedHtml).toContain('<ol> <li>List Item 1</li><li>List Item 2</li><li>List Item 3</li><li>List Item 4');
+	expect(normalizedHtml).toContain('<a title="" rel="nofollow noopener noreferrer" target="_blank">Rocket.Chat</a>');
+	expect(normalizedHtml).toContain('gabriel.engel@rocket.chat');
+	expect(normalizedHtml).toContain('+55991999999');
+	expect(normalizedHtml).toContain('<code>Inline code</code>');
+	expect(normalizedHtml).toContain('<pre><code class="language-typescript">const test = \'this is code\' </code></pre>');
+});
+
+it('should render html elements as expected using inline parser', async () => {
+	const { container } = render(<MarkdownText content={markdownText} variant='inline' />, {
+		wrapper: mockAppRoot().build(),
+		legacyRoot: true,
+	});
+
+	const normalizedHtml = normalizeHtml(container.innerHTML);
+
+	expect(normalizedHtml).toContain('# Heading 1');
+	expect(normalizedHtml).toContain(
+		'<strong>Bold with one asterisk</strong> <strong>Bold with two asterisks</strong> Lorem ipsum dolor sit amet, consectetur adipiscing elit.',
+	);
+	expect(normalizedHtml).toContain('## Heading 2');
+	expect(normalizedHtml).toContain(
+		'<em>Italic Text</em>: <em>Italic with one underscore</em> <em>Italic with two underscores</em> Lorem ipsum dolor sit amet',
+	);
+	expect(normalizedHtml).toContain('### Heading 3');
+	expect(normalizedHtml).toContain('<strong>Unordered List</strong> - List Item 1 - List Item 2 - List Item 3 - List Item 4');
+	expect(normalizedHtml).toContain('<strong>Ordered List</strong> 1. List Item 1 2. List Item 2 3. List Item 3 4. List Item 4');
+	expect(normalizedHtml).toContain(`<a title=\"\" rel=\"nofollow noopener noreferrer\" target=\"_blank\">Rocket.Chat</a>`);
+	expect(normalizedHtml).toContain(
+		`<a href=\"mailto:gabriel.engel@rocket.chat\" title=\"mailto:gabriel.engel@rocket.chat\" rel=\"nofollow noopener noreferrer\" target=\"_blank\">gabriel.engel@rocket.chat</a>`,
+	);
+	expect(normalizedHtml).toContain('+55991999999');
+	expect(normalizedHtml).toContain('Inline code');
+	expect(normalizedHtml).toContain(`typescript const test = 'this is code'`);
+});

apps/meteor/client/components/MarkdownText.tsx

@@ -20,12 +20,18 @@ const documentRenderer = new marked.Renderer();
 const inlineRenderer = new marked.Renderer();
 const inlineWithoutBreaks = new marked.Renderer();
 
-marked.Lexer.rules.gfm = {
-	...marked.Lexer.rules.gfm,
-	strong: /^\*\*(?=\S)([\s\S]*?\S)\*\*(?!\*)|^\*(?=\S)([\s\S]*?\S)\*(?!\*)/,
-	em: /^__(?=\S)([\s\S]*?\S)__(?!_)|^_(?=\S)([\s\S]*?\S)_(?!_)/,
+const walkTokens = (token: marked.Token) => {
+	const boldPattern = /^\*[^*]+\*$|^\*\*[^*]+\*\*$/;
+	const italicPattern = /^__(?=\S)([\s\S]*?\S)__(?!_)|^_(?=\S)([\s\S]*?\S)_(?!_)/;
+	if (boldPattern.test(token.raw)) {
+		token.type = 'strong';
+	} else if (italicPattern.test(token.raw)) {
+		token.type = 'em';
+	}
 };
 
+marked.use({ walkTokens });
+
 const linkMarked = (href: string | null, _title: string | null, text: string): string =>
 	`<a href="${href}" rel="nofollow noopener noreferrer">${text}</a> `;
 const paragraphMarked = (text: string): string => text;