Use ICU for ID_START and ID_CONTINUE for Unicode 9 data

src/char-predicates.h

 // Copyright 2011 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.
 
 #ifndef V8_CHAR_PREDICATES_H_
 #define V8_CHAR_PREDICATES_H_
 
 #include "src/globals.h"
 #include "src/unicode.h"
 
 namespace v8 {
 namespace internal {
 
 // Unicode character predicates as defined by ECMA-262, 3rd,
 // used for lexical analysis.
 
 inline int AsciiAlphaToLower(uc32 c);
 inline bool IsCarriageReturn(uc32 c);
 inline bool IsLineFeed(uc32 c);
 inline bool IsAsciiIdentifier(uc32 c);
 inline bool IsAlphaNumeric(uc32 c);
 inline bool IsDecimalDigit(uc32 c);
 inline bool IsHexDigit(uc32 c);
 inline bool IsOctalDigit(uc32 c);
 inline bool IsBinaryDigit(uc32 c);
 inline bool IsRegExpWord(uc32 c);
 inline bool IsRegExpNewline(uc32 c);
 
-struct V8_EXPORT_PRIVATE SupplementaryPlanes {
-  static bool IsIDStart(uc32 c);
-  static bool IsIDPart(uc32 c);
-};
-
-
-// ES6 draft section 11.6
+// ES#sec-names-and-keywords
 // This includes '_', '$' and '\', and ID_Start according to
 // http://www.unicode.org/reports/tr31/, which consists of categories
 // 'Lu', 'Ll', 'Lt', 'Lm', 'Lo', 'Nl', but excluding properties
 // 'Pattern_Syntax' or 'Pattern_White_Space'.
-// For code points in the SMPs, we can resort to ICU (if available).
+#ifdef V8_INTL_SUPPORT
+struct V8_EXPORT_PRIVATE IdentifierStart {
+  static bool Is(uc32 c);
+#else
 struct IdentifierStart {
+  // Non-BMP characters are not supported without I18N.
   static inline bool Is(uc32 c) {
-    if (c > 0xFFFF) return SupplementaryPlanes::IsIDStart(c);
-    return unibrow::ID_Start::Is(c);
+    return (c <= 0xFFFF) ? unibrow::ID_Start::Is(c) : false;
   }
+#endif
 };
 
-
-// ES6 draft section 11.6
+// ES#sec-names-and-keywords
 // This includes \u200c and \u200d, and ID_Continue according to
 // http://www.unicode.org/reports/tr31/, which consists of ID_Start,
 // the categories 'Mn', 'Mc', 'Nd', 'Pc', but excluding properties
 // 'Pattern_Syntax' or 'Pattern_White_Space'.
-// For code points in the SMPs, we can resort to ICU (if available).
+#ifdef V8_INTL_SUPPORT
+struct V8_EXPORT_PRIVATE IdentifierPart {
+  static bool Is(uc32 c);
+#else
 struct IdentifierPart {
   static inline bool Is(uc32 c) {
-    if (c > 0xFFFF) return SupplementaryPlanes::IsIDPart(c);
-    return unibrow::ID_Start::Is(c) || unibrow::ID_Continue::Is(c);
+    // Non-BMP charaacters are not supported without I18N.
+    if (c <= 0xFFFF) {
+      return unibrow::ID_Start::Is(c) || unibrow::ID_Continue::Is(c);
+    }
+    return false;
   }
+#endif
 };
 
-
 // ES6 draft section 11.2
 // This includes all code points of Unicode category 'Zs'.
-// \u180e stops being one as of Unicode 6.3.0, but ES6 adheres to Unicode 5.1,
-// so it is also included.
-// Further included are \u0009, \u000b, \u0020, \u00a0, \u000c, and \ufeff.
-// There are no category 'Zs' code points in the SMPs.
+// Further included are \u0009, \u000b, \u000c, and \ufeff.
+#ifdef V8_INTL_SUPPORT
+struct V8_EXPORT_PRIVATE WhiteSpace {
+  static bool Is(uc32 c);
+#else
 struct WhiteSpace {
   static inline bool Is(uc32 c) { return unibrow::WhiteSpace::Is(c); }
+#endif
 };
 
-
 // WhiteSpace and LineTerminator according to ES6 draft section 11.2 and 11.3
-// This consists of \000a, \000d, \u2028, and \u2029.
+// This includes all the characters with Unicode category 'Z' (= Zs+Zl+Zp)
+// as well as \u0009 - \u000d and \ufeff.
 struct WhiteSpaceOrLineTerminator {
   static inline bool Is(uc32 c) {
     return WhiteSpace::Is(c) || unibrow::LineTerminator::Is(c);
   }
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_CHAR_PREDICATES_H_