[regexp] Updates for unicode escapes in capture names

src/regexp/regexp-parser.cc

 // Copyright 2016 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/regexp/regexp-parser.h"
 
 #include "src/char-predicates-inl.h"
 #include "src/factory.h"
 #include "src/isolate.h"
 #include "src/objects-inl.h"
@@ skipping 682 matching lines @@
           // * a lookbehind assertion '(?<=' '(?<!'
           // * or a named capture '(?<'.
           //
           // Of these, only named captures are capturing groups.
           if (!FLAG_harmony_regexp_named_captures) break;
 
           Advance();
           if (current() != '<') break;
 
           if (FLAG_harmony_regexp_lookbehind) {
-            // TODO(jgruber): To be more future-proof we could test for
-            // IdentifierStart here once it becomes clear whether group names
-            // allow unicode escapes.
-            // https://github.com/tc39/proposal-regexp-named-groups/issues/23
             Advance();
             if (current() == '=' || current() == '!') break;
           }
 
           // Found a possible named capture. It could turn out to be a syntax
           // error (e.g. an unterminated or invalid name), but that distinction
           // does not matter for our purposes.
           has_named_captures_ = true;
         }
         capture_count++;
@@ skipping 59 matching lines @@
   const ScanMode scan_mode = ScanMode::FORCE_COMBINE_SURROGATE_PAIRS;
   Advance(scan_mode);
 
   bool at_start = true;
   while (true) {
     uc32 c = current();
     Advance(scan_mode);
 
     // Convert unicode escapes.
     if (c == '\\' && current() == 'u') {
-      // TODO(jgruber): Reconsider this once the spec has settled.
-      // https://github.com/tc39/proposal-regexp-named-groups/issues/23
       Advance(scan_mode);
       if (!ParseUnicodeEscape(&c)) {
         ReportError(CStrVector("Invalid Unicode escape sequence"));
         return nullptr;
       }
     }
 
     // The backslash char is misclassified as both ID_Start and ID_Continue.
     if (c == '\\') {
       ReportError(CStrVector("Invalid capture group name"));
@@ skipping 1074 matching lines @@
     return false;
   }
   terms_.Add(new (zone()) RegExpQuantifier(min, max, quantifier_type, atom),
              zone());
   LAST(ADD_TERM);
   return true;
 }
 
 }  // namespace internal
 }  // namespace v8