fix(lexer): improved identifier scanning

meriyah · Jun 22, 2019 · bb65cd7 · bb65cd7
1 parent 1e9d1b1
commit bb65cd7
Showing 1 changed file with 2 additions and 7 deletions.
diff --git a/src/lexer/identifier.ts b/src/lexer/identifier.ts
@@ -15,29 +15,24 @@ import { unicodeLookup } from '../unicode';
 export function scanIdentifier(parser: ParserState, context: Context): Token {
   let hasEscape: 0 | 1 = 0;
   let canBeKeyword: number = CharTypes[parser.nextCP] & CharFlags.KeywordCandidate;
-  parser.tokenValue = '';
   while ((CharTypes[nextCodePoint(parser)] & CharFlags.IdentifierPart) !== 0) {}
   parser.tokenValue = parser.source.slice(parser.tokenIndex, parser.index);
-  if (parser.nextCP > 0x7e) return scanIdentifierSlowCase(parser, context, hasEscape, canBeKeyword);
-
-  if ((CharTypes[parser.nextCP] & CharFlags.BackSlash) === 0) {
+  if ((CharTypes[parser.nextCP] & CharFlags.BackSlash) === 0 && parser.nextCP < 0x7e) {
     return descKeywordTable[parser.tokenValue] || Token.Identifier;
   }
 
   return scanIdentifierSlowCase(parser, context, hasEscape, canBeKeyword);
 }
-
 /**
  * Scans unicode identifier
  *
  * @param parser  Parser object
  * @param context Context masks
  */
 export function scanUnicodeIdentifier(parser: ParserState, context: Context): Token {
-  parser.tokenValue = '';
   const cookedChar = scanIdentifierUnicodeEscape(parser) as number;
   if (!isIdentifierPart(cookedChar)) report(parser, Errors.InvalidUnicodeEscapeSequence);
-  parser.tokenValue += fromCodePoint(cookedChar);
+  parser.tokenValue = fromCodePoint(cookedChar);
   return scanIdentifierSlowCase(parser, context, 1, CharTypes[cookedChar] & CharFlags.KeywordCandidate);
 }