[numeric separator] Ban implicit octal support

Bug: v8:7317
Change-Id: I20fb706c05852668a5a6ae8b69c150ae2e6b2f65
Reviewed-on: https://chromium-review.googlesource.com/960901Reviewed-by: Mathias Bynens <mathias@chromium.org>
Commit-Queue: Sathya Gunasekaran <gsathya@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51943}

src/messages.h

@@ -555,6 +555,8 @@ class ErrorUtils : public AllStatic {
   T(LetInLexicalBinding, "let is disallowed as a lexically bound name")        \
   T(LocaleMatcher, "Illegal value for localeMatcher:%")                        \
   T(NormalizationForm, "The normalization form should be one of %.")           \
+  T(ZeroDigitNumericSeparator,                                                 \
+    "Numeric separator can not be used after leading 0.")                      \
   T(NumberFormatRange, "% argument must be between 0 and 100")                 \
   T(TrailingNumericSeparator,                                                  \
     "Numeric separators are not allowed at the end of numeric literals")       \

src/parsing/scanner.cc

@@ -1342,49 +1342,10 @@ bool Scanner::ScanOctalDigits(int start_pos) {
   return true;
 }
 
-bool Scanner::ScanImplicitOctalDigitsWithNumericSeparators(
-    int start_pos, Scanner::NumberKind* kind) {
-  bool separator_seen = false;
-  while (true) {
-    if (c0_ == '_') {
-      Advance<false, false>();
-      if (c0_ == '_') {
-        ReportScannerError(Location(start_pos, source_pos()),
-                           MessageTemplate::kContinuousNumericSeparator);
-        return false;
-      }
-      separator_seen = true;
-      continue;
-    }
-
-    if (c0_ == '8' || c0_ == '9') {
-      *kind = DECIMAL_WITH_LEADING_ZERO;
-      return true;
-    }
-    if (c0_ < '0' || '7' < c0_) {
-      // Octal literal finished.
-      octal_pos_ = Location(start_pos, source_pos());
-      octal_message_ = MessageTemplate::kStrictOctalLiteral;
-      if (separator_seen) {
-        ReportScannerError(Location(start_pos, source_pos()),
-                           MessageTemplate::kTrailingNumericSeparator);
-        return false;
-      }
-      return true;
-    }
-    separator_seen = false;
-    AddLiteralCharAdvance();
-  }
-}
-
 bool Scanner::ScanImplicitOctalDigits(int start_pos,
                                       Scanner::NumberKind* kind) {
   *kind = IMPLICIT_OCTAL;
 
-  if (allow_harmony_numeric_separator()) {
-    return ScanImplicitOctalDigitsWithNumericSeparators(start_pos, kind);
-  }
-
   while (true) {
     // (possible) octal number
     if (c0_ == '8' || c0_ == '9') {
@@ -1469,6 +1430,10 @@ Token::Value Scanner::ScanNumber(bool seen_period) {
         }
       } else if (c0_ == '8' || c0_ == '9') {
         kind = DECIMAL_WITH_LEADING_ZERO;
+      } else if (allow_harmony_numeric_separator() && c0_ == '_') {
+        ReportScannerError(Location(source_pos(), source_pos() + 1),
+                           MessageTemplate::kZeroDigitNumericSeparator);
+        return Token::ILLEGAL;
       }
     }
 

src/parsing/scanner.h

@@ -747,8 +747,6 @@ class Scanner {
   bool ScanSignedInteger(int start_pos);
   bool ScanOctalDigits(int start_pos);
   bool ScanImplicitOctalDigits(int start_pos, NumberKind* kind);
-  bool ScanImplicitOctalDigitsWithNumericSeparators(int start_pos,
-                                                    NumberKind* kind);
 
   Token::Value ScanNumber(bool seen_period);
   Token::Value ScanIdentifierOrKeyword();

test/cctest/test-parsing.cc

@@ -1523,30 +1523,16 @@ TEST(NumericSeparatorErrors) {
   RunParserSyncTest(context_data, statement_data, kError);
 }
 
-TEST(NumericSeparatorImplicitOctals) {
-  v8::HandleScope handles(CcTest::isolate());
-  v8::Local<v8::Context> context = v8::Context::New(CcTest::isolate());
-  v8::Context::Scope context_scope(context);
-
-  const char* context_data[][2] = {
-      {"", ""}, {nullptr, nullptr}, {nullptr, nullptr}};
-  const char* statement_data[] = {"07_7_7", "0_7_7_7", "0_777", nullptr};
-
-  static const ParserFlag flags[] = {kAllowHarmonyNumericSeparator};
-  RunParserSyncTest(context_data, statement_data, kSuccess, nullptr, 0, flags,
-                    1);
-
-  RunParserSyncTest(context_data, statement_data, kError);
-}
-
 TEST(NumericSeparatorImplicitOctalsErrors) {
   v8::HandleScope handles(CcTest::isolate());
   v8::Local<v8::Context> context = v8::Context::New(CcTest::isolate());
   v8::Context::Scope context_scope(context);
 
   const char* context_data[][2] = {
-      {"", ""}, {nullptr, nullptr}, {nullptr, nullptr}};
-  const char* statement_data[] = {"07_7_7_", "07__77", "0__777", nullptr};
+      {"", ""}, {"\"use strict\";", ""}, {nullptr, nullptr}};
+  const char* statement_data[] = {"00_122",  "0_012",  "07_7_7",
+                                  "0_7_7_7", "0_777",  "07_7_7_",
+                                  "07__77",  "0__777", nullptr};
 
   static const ParserFlag flags[] = {kAllowHarmonyNumericSeparator};
   RunParserSyncTest(context_data, statement_data, kError, nullptr, 0, flags, 1,

test/mjsunit/harmony/numeric-separator.js

@@ -24,11 +24,6 @@
   const octal = 0o7_7_7;
   assertEquals(octal, 0o777);
 }
-{
-  const implicitOctal = 07_7_7;
-  assertEquals(implicitOctal, 0o777);
-}
-
 {
   let exception = false;
   try {
@@ -66,3 +61,4 @@ assertThrows('0o_777', SyntaxError);
 assertThrows('0o7__77', SyntaxError);
 assertThrows('0777_', SyntaxError);
 assertThrows('07__77', SyntaxError);
+assertThrows('07_7_7', SyntaxError);