Fix a double dash in the previewer if an @param jsdoc tag has a hyphen after the param name (#53365)

* Fix a double dash if the @param has a hyphen

* Moved into the other regex

* Add test for ignoring hypen after @param

* Fixed test and moved to previewer.test.ts

extensions/typescript-language-features/src/test/previewer.test.ts

@@ -0,0 +1,22 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+import * as assert from 'assert';
+import 'mocha';
+import { tagsMarkdownPreview } from '../utils/previewer';
+
+suite('typescript.previewer', () => {
+	test('Should ignore hyphens after a param tag', async () => {
+		assert.strictEqual(
+			tagsMarkdownPreview([
+				{
+					name: 'param',
+					text: 'a - b'
+				}
+			]),
+			'*@param* `a` — b');
+	});
+});
+

extensions/typescript-language-features/src/utils/previewer.ts

@@ -27,7 +27,7 @@ function getTagBodyText(tag: Proto.JSDocTagInfo): string | undefined {
 function getTagDocumentation(tag: Proto.JSDocTagInfo): string | undefined {
 	switch (tag.name) {
 		case 'param':
-			const body = (tag.text || '').split(/^([\w\.]+)\s*/);
+			const body = (tag.text || '').split(/^([\w\.]+)\s*-?\s*/);
 			if (body && body.length === 3) {
 				const param = body[1];
 				const doc = body[2];