From 30b4dbc19bea6b5415f4826250483af38381fb94 Mon Sep 17 00:00:00 2001
From: Shelley Vohr <shelley.vohr@gmail.com>
Date: Thu, 27 Feb 2020 14:34:50 -0800
Subject: [PATCH] repl: allow recovery for wrapped eval

---
 lib/repl.js | 30 +++++++++++++++++++++++++++---
 1 file changed, 27 insertions(+), 3 deletions(-)

diff --git a/lib/repl.js b/lib/repl.js
index 00820953b553cf..0b172a748169e1 100644
--- a/lib/repl.js
+++ b/lib/repl.js
@@ -69,8 +69,17 @@ const {
 } = require('internal/modules/cjs/helpers');
 const {
   isIdentifierStart,
-  isIdentifierChar
+  isIdentifierChar,
+  Parser
 } = require('internal/deps/acorn/acorn/dist/acorn');
+const privateMethods =
+  require('internal/deps/acorn-plugins/acorn-private-methods/index');
+const classFields =
+  require('internal/deps/acorn-plugins/acorn-class-fields/index');
+const numericSeparator =
+  require('internal/deps/acorn-plugins/acorn-numeric-separator/index');
+const staticClassFeatures =
+  require('internal/deps/acorn-plugins/acorn-static-class-features/index');
 const {
   decorateErrorStack,
   isError,
@@ -332,8 +341,23 @@ function REPLServer(prompt,
     // an expression.  Note that if the above condition changes,
     // lib/internal/repl/utils.js needs to be changed to match.
     if (/^\s*{/.test(code) && !/;\s*$/.test(code)) {
-      code = `(${code.trim()})\n`;
-      wrappedCmd = true;
+      const parser = Parser.extend(
+        privateMethods,
+        classFields,
+        numericSeparator,
+        staticClassFeatures
+      );
+
+      // Ensure that the wrapped expression is valid,
+      // otherwise proceed unwrapped.
+      try {
+        parser.parse(`(${code.trim()})\n`, {
+          ecmaVersion: 11,
+          allowAwaitOutsideFunction: true
+        });
+        code = `(${code.trim()})\n`;
+        wrappedCmd = true;
+      } catch {}
     }
 
     if (experimentalREPLAwait && code.includes('await')) {