fix(lexer): tweaked ident scanning

meriyah · May 26, 2019 · a205210 · a205210
1 parent 3708214
commit a205210
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Showing 2 changed files with 21 additions and 35 deletions.
diff --git a/src/lexer/identifier.ts b/src/lexer/identifier.ts
@@ -7,8 +7,8 @@ import { report, Errors } from '../errors';
 import { unicodeLookup } from '../unicode';
 
 export function scanIdentifier(parser: ParserState, context: Context): Token {
-  let hasEscape = false;
-  let canBeKeyword = (CharTypes[parser.currentCodePoint] & CharFlags.KeywordCandidate) !== 0;
+  let hasEscape: 0 | 1 = 0;
+  let canBeKeyword: number = CharTypes[parser.currentCodePoint] & CharFlags.KeywordCandidate;
   parser.tokenValue = '';
   if (parser.currentCodePoint <= 0x7e) {
     if ((CharTypes[parser.currentCodePoint] & CharFlags.BackSlash) === 0) {
@@ -20,10 +20,10 @@ export function scanIdentifier(parser: ParserState, context: Context): Token {
         return descKeywordTable[parser.tokenValue] || Token.Identifier;
       }
     } else {
-      hasEscape = true;
+      hasEscape = 1;
       const code = scanIdentifierUnicodeEscape(parser);
       if (!isIdentifierPart(code)) report(parser, Errors.InvalidUnicodeEscapeSequence);
-      canBeKeyword = (CharTypes[code] & CharFlags.KeywordCandidate) !== 0;
+      canBeKeyword = CharTypes[code] & CharFlags.KeywordCandidate;
       parser.tokenValue += fromCodePoint(code);
     }
   }
@@ -34,17 +34,17 @@ export function scanIdentifier(parser: ParserState, context: Context): Token {
 export function scanIdentifierSlowCase(
   parser: ParserState,
   context: Context,
-  hasEscape: boolean,
-  canBeKeyword: boolean
+  hasEscape: 0 | 1,
+  canBeKeyword: number
 ): Token {
   let start = parser.index;
   while (parser.index < parser.length) {
-    if ((parser.currentCodePoint & 8) === 8 && parser.currentCodePoint === Chars.Backslash) {
+    if (CharTypes[parser.currentCodePoint] & CharFlags.BackSlash) {
       parser.tokenValue += parser.source.slice(start, parser.index);
-      hasEscape = true;
+      hasEscape = 1;
       const code = scanIdentifierUnicodeEscape(parser);
       if (!isIdentifierPart(code)) report(parser, Errors.InvalidUnicodeEscapeSequence);
-      canBeKeyword = canBeKeyword && (CharTypes[code] & CharFlags.KeywordCandidate) !== 0;
+      canBeKeyword = canBeKeyword && CharTypes[code] & CharFlags.KeywordCandidate;
       parser.tokenValue += fromCodePoint(code);
       start = parser.index;
     } else if (
@@ -65,15 +65,16 @@ export function scanIdentifierSlowCase(
 
   if (canBeKeyword && (length >= 2 && length <= 11)) {
     const keyword: Token | undefined = descKeywordTable[parser.tokenValue as string];
-    if (keyword === undefined) return Token.Identifier;
 
-    if (keyword === Token.YieldKeyword) return keyword;
-
-    if ((keyword & Token.FutureReserved) === Token.FutureReserved) {
-      return context & Context.Strict && hasEscape ? Token.EscapedFutureReserved : keyword;
-    }
-
-    return context & Context.Strict && (keyword === Token.LetKeyword || keyword === Token.StaticKeyword)
+    return keyword === void 0
+      ? Token.Identifier
+      : keyword === Token.YieldKeyword
+      ? keyword
+      : (keyword & Token.FutureReserved) === Token.FutureReserved
+      ? context & Context.Strict && hasEscape
+        ? Token.EscapedFutureReserved
+        : keyword
+      : context & Context.Strict && (keyword === Token.LetKeyword || keyword === Token.StaticKeyword)
       ? Token.EscapedFutureReserved
       : Token.EscapedReserved;
   }

diff --git a/test/test262-parser-tests/parser-tests.ts b/test/test262-parser-tests/parser-tests.ts
@@ -6,17 +6,12 @@ const Test262Dir = 'node_modules/test262-parser-tests';
 
 const expectations = {
   pass: [
-    'ba00173ff473e7da.js', //
-    '946bee37652a31fa.js', //
+    'ba00173ff473e7da.js',
+    '946bee37652a31fa.js',
     '8b8edcb36909900b.js',
-    '6a220df693ce521c.js', //
     '5d5b9de6d9b95f3e.js',
-    '5a2a8e992fa4fe37.js', //
+    '5a2a8e992fa4fe37.js',
     '4f5419fe648c691b.js',
-    '44f31660bd715f05.js', //
-    '08a39e4289b0c3f3.js',
-    '046a0bb70d03d0cc.js',
-    '300a638d978d0f2c.js',
     '110fa1efdd0868b8.js',
     '1a1c717109ab67e1.js',
     '206ebb4e67a6daa9.js',
@@ -33,11 +28,6 @@ const expectations = {
   ],
   explicit: [
     '3b36d546985cd9cb.js',
-    '44f31660bd715f05.js',
-    '300a638d978d0f2c.js',
-    '0e3ca454ddfb4729.js',
-    '08a39e4289b0c3f3.js',
-    '046a0bb70d03d0cc.js',
     '110fa1efdd0868b8.js',
     '1a1c717109ab67e1.js',
     '206ebb4e67a6daa9.js',
@@ -49,19 +39,14 @@ const expectations = {
     'e4a43066905a597b.js',
     'f872cf801765a723.js',
     'bf49ec8d96884562.js',
-    'b7b057684207633b.js',
-    '9f5a6dae7645976a.js',
     '8af69d8f15295ed2.js',
     '84633c379e4010bf.js',
     '7fc173197c3cc75d.js',
     '78c215fabdf13bae.js',
     '66e383bfd18e66ab.js',
     '647e21f8f157c338.js',
-    '3dbb6e166b14a6c0.js',
     '324ab48c6d89125d.js',
     '2687d6d9043bd5cb.js',
-    '1395e3a9d2acf65c.js',
-    'fd2a45941e114896.js',
     '7b876ca5139f1ca8.js',
     '3bc2b27a7430f818.js',
     'e3fbcf63d7e43ead.js',