1 files changed, 155 insertions, 0 deletions
diff --git a/js/src/util/Identifier.cpp b/js/src/util/Identifier.cpp
new file mode 100644
index 0000000000..0de987180a
--- /dev/null
+++ b/js/src/util/Identifier.cpp
@@ -0,0 +1,155 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: set ts=8 sts=2 et sw=2 tw=80:
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "util/Identifier.h"
+
+#include "mozilla/Assertions.h"  // MOZ_ASSERT
+
+#include <stddef.h>  // size_t
+
+#include "js/GCAPI.h"      // JS::AutoCheckCannotGC
+#include "js/TypeDecls.h"  // JS::Latin1Char
+#include "util/Unicode.h"  // unicode::{IsIdentifierStart, IsIdentifierPart, IsIdentifierStartASCII, IsIdentifierPartASCII, IsLeadSurrogate, IsTrailSurrogate, UTF16Decode}
+#include "vm/StringType.h"  // JSLinearString
+
+using namespace js;
+
+bool js::IsIdentifier(JSLinearString* str) {
+  JS::AutoCheckCannotGC nogc;
+  MOZ_ASSERT(str);
+  if (str->hasLatin1Chars()) {
+    return IsIdentifier(str->latin1Chars(nogc), str->length());
+  }
+  return IsIdentifier(str->twoByteChars(nogc), str->length());
+}
+
+bool js::IsIdentifierNameOrPrivateName(JSLinearString* str) {
+  JS::AutoCheckCannotGC nogc;
+  MOZ_ASSERT(str);
+  if (str->hasLatin1Chars()) {
+    return IsIdentifierNameOrPrivateName(str->latin1Chars(nogc), str->length());
+  }
+  return IsIdentifierNameOrPrivateName(str->twoByteChars(nogc), str->length());
+}
+
+bool js::IsIdentifier(const JS::Latin1Char* chars, size_t length) {
+  if (length == 0) {
+    return false;
+  }
+
+  if (!unicode::IsIdentifierStart(char16_t(*chars))) {
+    return false;
+  }
+
+  const JS::Latin1Char* end = chars + length;
+  while (++chars != end) {
+    if (!unicode::IsIdentifierPart(char16_t(*chars))) {
+      return false;
+    }
+  }
+
+  return true;
+}
+
+bool js::IsIdentifierASCII(char c) {
+  return unicode::IsIdentifierStartASCII(c);
+}
+
+bool js::IsIdentifierASCII(char c1, char c2) {
+  return unicode::IsIdentifierStartASCII(c1) &&
+         unicode::IsIdentifierPartASCII(c2);
+}
+
+bool js::IsIdentifierNameOrPrivateName(const JS::Latin1Char* chars,
+                                       size_t length) {
+  if (length == 0) {
+    return false;
+  }
+
+  // Skip over any private name marker.
+  if (*chars == '#') {
+    ++chars;
+    --length;
+  }
+
+  return IsIdentifier(chars, length);
+}
+
+static char32_t GetSingleCodePoint(const char16_t** p, const char16_t* end) {
+  using namespace js;
+
+  if (MOZ_UNLIKELY(unicode::IsLeadSurrogate(**p)) && *p + 1 < end) {
+    char16_t lead = **p;
+    char16_t maybeTrail = *(*p + 1);
+    if (unicode::IsTrailSurrogate(maybeTrail)) {
+      *p += 2;
+      return unicode::UTF16Decode(lead, maybeTrail);
+    }
+  }
+
+  char32_t codePoint = **p;
+  (*p)++;
+  return codePoint;
+}
+
+bool js::IsIdentifier(const char16_t* chars, size_t length) {
+  if (length == 0) {
+    return false;
+  }
+
+  const char16_t* p = chars;
+  const char16_t* end = chars + length;
+  char32_t codePoint;
+
+  codePoint = GetSingleCodePoint(&p, end);
+  if (!unicode::IsIdentifierStart(codePoint)) {
+    return false;
+  }
+
+  while (p < end) {
+    codePoint = GetSingleCodePoint(&p, end);
+    if (!unicode::IsIdentifierPart(codePoint)) {
+      return false;
+    }
+  }
+
+  return true;
+}
+
+bool js::IsIdentifierNameOrPrivateName(const char16_t* chars, size_t length) {
+  if (length == 0) {
+    return false;
+  }
+
+  const char16_t* p = chars;
+  const char16_t* end = chars + length;
+  char32_t codePoint;
+
+  codePoint = GetSingleCodePoint(&p, end);
+
+  // Skip over any private name marker.
+  if (codePoint == '#') {
+    // The identifier part of a private name mustn't be empty.
+    if (length == 1) {
+      return false;
+    }
+
+    codePoint = GetSingleCodePoint(&p, end);
+  }
+
+  if (!unicode::IsIdentifierStart(codePoint)) {
+    return false;
+  }
+
+  while (p < end) {
+    codePoint = GetSingleCodePoint(&p, end);
+    if (!unicode::IsIdentifierPart(codePoint)) {
+      return false;
+    }
+  }
+
+  return true;
+}