fix #58494

src/vs/editor/contrib/snippet/snippetParser.ts

@@ -796,9 +796,10 @@ export class SnippetParser {
 			}
 			let value: string;
 			if (value = this._accept(TokenType.Backslash, true)) {
-				// \, or \|
+				// \, \|, or \\
 				value = this._accept(TokenType.Comma, true)
 					|| this._accept(TokenType.Pipe, true)
+					|| this._accept(TokenType.Backslash, true)
 					|| value;
 			} else {
 				value = this._accept(undefined, true);

src/vs/editor/contrib/snippet/test/snippetParser.test.ts

@@ -353,6 +353,12 @@ suite('SnippetParser', () => {
 		assertText('${1||}', '${1||}');
 	});
 
+	test('Backslash character escape in choice tabstop doesn\'t work #58494', function () {
+
+		const { placeholders } = new SnippetParser().parse('${1|\\,,},$,\\|,\\\\|}');
+		assert.equal(placeholders.length, 1);
+		assert.ok(placeholders[0].choice instanceof Choice);
+	});
 
 	test('Parser, only textmate', () => {
 		const p = new SnippetParser();