Use the code point iterator in equality comparisons to C strings.

runtime/vm/object.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/object.h"
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "vm/assembler.h"
 #include "vm/bigint_operations.h"
@@ skipping 10017 matching lines @@
 
   const String& other_string = String::Cast(other);
   if (this->HasHash() && other_string.HasHash() &&
       (this->Hash() != other_string.Hash())) {
     return false;  // Both sides have a hash code and it does not match.
   }
   return Equals(other_string, 0, other_string.Length());
 }
 
 
-bool String::Equals(const char* utf8_array) const {
-  ASSERT(utf8_array != NULL);
-  intptr_t len = strlen(utf8_array);
-  for (intptr_t i = 0; i < this->Length(); ++i) {
-    if (*utf8_array == '\0') {
+bool String::Equals(const char* str) const {

[siva, 2012/11/20 19:47:32]

yes cstr would be a better name.
Also please change the header file too.
(maybe the comment should state that the input is a c style
null terminated string with utf8 characters).

[cshapiro, 2012/11/20 23:41:12]

Done.

All of the C-strings in the dart VM are assumed to be UTF-8 encoded so there
should be no confusion about the encoding.

+  ASSERT(str != NULL);
+  CodePointIterator it(*this);
+  intptr_t len = strlen(str);
+  while (it.Next()) {
+    if (*str == '\0') {
       // Lengths don't match.
       return false;
     }
     int32_t ch;
-    intptr_t consumed = Utf8::Decode(
-        reinterpret_cast<const uint8_t*>(utf8_array),
-        len,
-        &ch);
-    if (consumed == 0 || this->CharAt(i) != ch) {
+    intptr_t consumed = Utf8::Decode(reinterpret_cast<const uint8_t*>(str),
+                                     len,
+                                     &ch);
+    if (consumed == 0 || it.Current() != ch) {
       return false;
     }
-    utf8_array += consumed;
+    str += consumed;
     len -= consumed;
   }
-  return *utf8_array == '\0';
+  return *str == '\0';
 }

[siva, 2012/11/20 19:47:32]

We should add a test case for this in order to ensure that
we regress it.

[cshapiro, 2012/11/20 23:41:12]

Done.

 
 
 bool String::Equals(const uint8_t* latin1_array, intptr_t len) const {
   if (len != this->Length()) {
     // Lengths don't match.
     return false;
   }
 
   for (intptr_t i = 0; i < len; i++) {
     if (this->CharAt(i) != latin1_array[i]) {
@@ skipping 2092 matching lines @@
   }
   return result.raw();
 }
 
 
 const char* WeakProperty::ToCString() const {
   return "_WeakProperty";
 }
 
 }  // namespace dart