repl: support mult-line string-keyed objects

isRecoverableError is completely reimplemented using acorn and an
acorn plugin that examines the state of the parser at the time of the
error to determine if the code could be completed on a subsequent line.

PR-URL: https://github.com/nodejs/node/pull/21805
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Tiancheng "Timothy" Gu <timothygu99@gmail.com>
Reviewed-By: John-David Dalton <john.david.dalton@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

1 files changed, 3 insertions, 71 deletions

diff --git a/lib/repl.js b/lib/repl.js
index 92c90de7bb..4a01595ce1 100644
--- a/lib/repl.js
+++ b/lib/repl.js
@@ -73,6 +73,7 @@ const {
 } = require('internal/errors').codes;
 const { sendInspectorCommand } = require('internal/util/inspector');
 const { experimentalREPLAwait } = process.binding('config');
+const { isRecoverableError } = require('internal/repl/recoverable');
 
 // Lazy-loaded.
 let processTopLevelAwait;
@@ -227,7 +228,8 @@ function REPLServer(prompt,
       // It's confusing for `{ a : 1 }` to be interpreted as a block
       // statement rather than an object literal.  So, we first try
       // to wrap it in parentheses, so that it will be interpreted as
-      // an expression.
+      // an expression.  Note that if the above condition changes,
+      // lib/internal/repl/recoverable.js needs to be changed to match.
       code = `(${code.trim()})\n`;
       wrappedCmd = true;
     }
@@ -1505,76 +1507,6 @@ function regexpEscape(s) {
   return s.replace(/[-[\]{}()*+?.,\\^$|#\s]/g, '\\$&');
 }
 
-// If the error is that we've unexpectedly ended the input,
-// then let the user try to recover by adding more input.
-function isRecoverableError(e, code) {
-  if (e && e.name === 'SyntaxError') {
-    var message = e.message;
-    if (message === 'Unterminated template literal' ||
-        message === 'Unexpected end of input') {
-      return true;
-    }
-
-    if (message === 'missing ) after argument list') {
-      const frames = e.stack.split(/\r?\n/);
-      const pos = frames.findIndex((f) => f.match(/^\s*\^+$/));
-      return pos > 0 && frames[pos - 1].length === frames[pos].length;
-    }
-
-    if (message === 'Invalid or unexpected token')
-      return isCodeRecoverable(code);
-  }
-  return false;
-}
-
-// Check whether a code snippet should be forced to fail in the REPL.
-function isCodeRecoverable(code) {
-  var current, previous, stringLiteral;
-  var isBlockComment = false;
-  var isSingleComment = false;
-  var isRegExpLiteral = false;
-  var lastChar = code.charAt(code.length - 2);
-  var prevTokenChar = null;
-
-  for (var i = 0; i < code.length; i++) {
-    previous = current;
-    current = code[i];
-
-    if (previous === '\\' && (stringLiteral || isRegExpLiteral)) {
-      current = null;
-    } else if (stringLiteral) {
-      if (stringLiteral === current) {
-        stringLiteral = null;
-      }
-    } else if (isRegExpLiteral && current === '/') {
-      isRegExpLiteral = false;
-    } else if (isBlockComment && previous === '*' && current === '/') {
-      isBlockComment = false;
-    } else if (isSingleComment && current === '\n') {
-      isSingleComment = false;
-    } else if (!isBlockComment && !isRegExpLiteral && !isSingleComment) {
-      if (current === '/' && previous === '/') {
-        isSingleComment = true;
-      } else if (previous === '/') {
-        if (current === '*') {
-          isBlockComment = true;
-          // Distinguish between a division operator and the start of a regex
-          // by examining the non-whitespace character that precedes the /
-        } else if ([null, '(', '[', '{', '}', ';'].includes(prevTokenChar)) {
-          isRegExpLiteral = true;
-        }
-      } else {
-        if (current.trim()) prevTokenChar = current;
-        if (current === '\'' || current === '"') {
-          stringLiteral = current;
-        }
-      }
-    }
-  }
-
-  return stringLiteral ? lastChar === '\\' : isBlockComment;
-}
-
 function Recoverable(err) {
   this.err = err;
 }