diff --git a/extensions/typescript/src/typescriptMain.ts b/extensions/typescript/src/typescriptMain.ts
index 122da74dacb..3474eb29b85 100644
--- a/extensions/typescript/src/typescriptMain.ts
+++ b/extensions/typescript/src/typescriptMain.ts
@@ -300,7 +300,7 @@ class LanguageProvider {
 						// ^(.*\*/)?\s*\}.*$
 						decreaseIndentPattern: /^((?!.*?\/\*).*\*\/)?\s*[\}\]\)].*$/,
 						// ^.*\{[^}"']*$
-						increaseIndentPattern: /^.*(\{[^}"'`]*|\([^)"'`]*|\[[^\]"'`]*)$/,
+						increaseIndentPattern: /^((?!\/\/).)*(\{[^}"'`]*|\([^)"'`]*|\[[^\]"'`]*)$/,
 						indentNextLinePattern: /^\s*(for|while|if|else)\b(?!.*[;{}]\s*(\/\/.*|\/[*].*[*]\/\s*)?$)/
 					},
 					wordPattern: /(-?\d*\.\d\w*)|([^\`\~\!\@\#\%\^\&\*\(\)\-\=\+\[\{\]\}\\\|\;\:\'\"\,\.\<\>\/\?\s]+)/g,
diff --git a/src/vs/editor/test/common/controller/cursor.test.ts b/src/vs/editor/test/common/controller/cursor.test.ts
index 6fe0f627808..7c62a32907c 100644
--- a/src/vs/editor/test/common/controller/cursor.test.ts
+++ b/src/vs/editor/test/common/controller/cursor.test.ts
@@ -2282,7 +2282,7 @@ suite('Editor Controller - Cursor Configuration', () => {
 suite('Editor Controller - Indentation Rules', () => {
 	let mode = new IndentRulesMode({
 		decreaseIndentPattern: /^\s*((?!\S.*\/[*]).*[*]\/\s*)?[})\]]|^\s*(case\b.*|default):\s*(\/\/.*|\/[*].*[*]\/\s*)?$/,
-		increaseIndentPattern: /(\{[^}"'`]*|\([^)"']*|\[[^\]"']*|^\s*(\{\}|\(\)|\[\]|(case\b.*|default):))\s*(\/\/.*|\/[*].*[*]\/\s*)?$/,
+		increaseIndentPattern: /^((?!\/\/).)*(\{[^}"'`]*|\([^)"']*|\[[^\]"']*|^\s*(\{\}|\(\)|\[\]|(case\b.*|default):))\s*(\/\/.*|\/[*].*[*]\/\s*)?$/,
 		indentNextLinePattern: /^\s*(for|while|if|else)\b(?!.*[;{}]\s*(\/\/.*|\/[*].*[*]\/\s*)?$)/,
 		unIndentedLinePattern: /^(?!.*([;{}]|\S:)\s*(\/\/.*|\/[*].*[*]\/\s*)?$)(?!.*(\{[^}"']*|\([^)"']*|\[[^\]"']*|^\s*(\{\}|\(\)|\[\]|(case\b.*|default):))\s*(\/\/.*|\/[*].*[*]\/\s*)?$)(?!^\s*((?!\S.*\/[*]).*[*]\/\s*)?[})\]]|^\s*(case\b.*|default):\s*(\/\/.*|\/[*].*[*]\/\s*)?$)(?!^\s*(for|while|if|else)\b(?!.*[;{}]\s*(\/\/.*|\/[*].*[*]\/\s*)?$))/
 	});
@@ -3080,6 +3080,26 @@ suite('Editor Controller - Indentation Rules', () => {
 			assert.equal(model.getLineContent(2), '\t  ) {', 'This line should not decrease indent');
 		});
 	});
+
+	test('bug 29972: if a line is line comment, open bracket should not indent next line', () => {
+		usingCursor({
+			text: [
+				'if (true) {',
+				'\t// {',
+				'\t\t'
+			],
+			languageIdentifier: mode.getLanguageIdentifier(),
+			modelOpts: { insertSpaces: false, tabSize: 4, detectIndentation: false, defaultEOL: DefaultEndOfLine.LF, trimAutoWhitespace: true },
+			editorOpts: { autoIndent: true }
+		}, (model, cursor) => {
+			moveTo(cursor, 3, 3, false);
+			assertCursor(cursor, new Selection(3, 3, 3, 3));
+
+			cursorCommand(cursor, H.Type, { text: '}' }, 'keyboard');
+			assertCursor(cursor, new Selection(3, 2, 3, 2));
+			assert.equal(model.getLineContent(3), '}');
+		});
+	});
 });
 
 interface ICursorOpts {