[Intl] move isWellFormedCurrencyCode to C++

Bug: v8:7979
Cq-Include-Trybots: luci.v8.try:v8_linux_noi18n_rel_ng
Change-Id: Ib02a634dd82b6cef647e23464401af4acccc21f1
Reviewed-on: https://chromium-review.googlesource.com/1151049
Commit-Queue: Frank Tang <ftang@chromium.org>
Reviewed-by: Sathya Gunasekaran <gsathya@chromium.org>
Cr-Commit-Position: refs/heads/master@{#54735}

src/js/intl.js

@@ -1228,17 +1228,6 @@ DEFINE_METHOD(
   }
 );
 
-/**
- * Verifies that the input is a well-formed ISO 4217 currency code.
- * Don't uppercase to test. It could convert invalid code into a valid one.
- * For example \u00DFP (Eszett+P) becomes SSP.
- */
-function isWellFormedCurrencyCode(currency) {
-  return typeof currency === "string" && currency.length === 3 &&
-      IS_NULL(%regexp_internal_match(/[^A-Za-z]/, currency));
-}
-
-
 function defaultNumberOption(value, min, max, fallback, property) {
   if (!IS_UNDEFINED(value)) {
     value = TO_NUMBER(value);
@@ -1308,7 +1297,7 @@ function CreateNumberFormat(locales, options) {
     'style', 'string', ['decimal', 'percent', 'currency'], 'decimal'));
 
   var currency = getOption('currency', 'string');
-  if (!IS_UNDEFINED(currency) && !isWellFormedCurrencyCode(currency)) {
+  if (!IS_UNDEFINED(currency) && !%IsWellFormedCurrencyCode(currency)) {
     throw %make_range_error(kInvalidCurrencyCode, currency);
   }
 

src/objects/intl-objects.cc

@@ -1761,5 +1761,33 @@ MaybeHandle<JSObject> Intl::CreateNumberFormat(Isolate* isolate,
   return local_object;
 }
 
+namespace {
+
+bool IsAToZ(char ch) {
+  return (('A' <= ch) && (ch <= 'Z')) || (('a' <= ch) && (ch <= 'z'));
+}
+
+}  // namespace
+
+// Verifies that the input is a well-formed ISO 4217 currency code.
+// ecma402/#sec-currency-codes
+bool Intl::IsWellFormedCurrencyCode(Isolate* isolate, Handle<String> currency) {
+  // 2. If the number of elements in normalized is not 3, return false.
+  if (currency->length() != 3) return false;
+
+  currency = String::Flatten(isolate, currency);
+  {
+    DisallowHeapAllocation no_gc;
+    String::FlatContent flat = currency->GetFlatContent();
+
+    // 1. Let normalized be the result of mapping currency to upper case as
+    // described in 6.1. 3. If normalized contains any character that is not in
+    // the range "A" to "Z" (U+0041 to U+005A), return false. 4. Return true.
+    // Don't uppercase to test. It could convert invalid code into a valid one.
+    // For example \u00DFP (Eszett+P) becomes SSP.
+    return (IsAToZ(flat.Get(0)) && IsAToZ(flat.Get(1)) && IsAToZ(flat.Get(2)));
+  }
+}
+
 }  // namespace internal
 }  // namespace v8

src/objects/intl-objects.h

@@ -310,6 +310,10 @@ class Intl {
   V8_WARN_UNUSED_RESULT static MaybeHandle<JSObject> CreateNumberFormat(
       Isolate* isolate, Handle<String> locale, Handle<JSObject> options,
       Handle<JSObject> resolved);
+
+  // ecma402/#sec-iswellformedcurrencycode
+  static bool IsWellFormedCurrencyCode(Isolate* isolate,
+                                       Handle<String> currency);
 };
 
 }  // namespace internal

src/runtime/runtime-intl.cc

@@ -116,6 +116,14 @@ RUNTIME_FUNCTION(Runtime_GetDefaultICULocale) {
   return *Intl::DefaultLocale(isolate);
 }
 
+RUNTIME_FUNCTION(Runtime_IsWellFormedCurrencyCode) {
+  HandleScope scope(isolate);
+  DCHECK_EQ(1, args.length());
+  CONVERT_ARG_HANDLE_CHECKED(String, currency, 0);
+  return *(isolate->factory()->ToBoolean(
+      Intl::IsWellFormedCurrencyCode(isolate, currency)));
+}
+
 RUNTIME_FUNCTION(Runtime_IsInitializedIntlObjectOfType) {
   HandleScope scope(isolate);
 

src/runtime/runtime.h

@@ -222,6 +222,7 @@ namespace internal {
   F(InternalNumberFormat, 2, 1)              \
   F(IntlUnwrapReceiver, 5, 1)                \
   F(IsInitializedIntlObjectOfType, 2, 1)     \
+  F(IsWellFormedCurrencyCode, 1, 1)          \
   F(MarkAsInitializedIntlObjectOfType, 2, 1) \
   F(PluralRulesSelect, 2, 1)                 \
   F(StringLocaleConvertCase, 3, 1)           \