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

runtime/vm/object.cc

Index: runtime/vm/object.cc
diff --git a/runtime/vm/object.cc b/runtime/vm/object.cc
index cb15a98b12cae59a0536892b14372ca4be284815..cf65b01cc5bceea73b1ab0c3245a9536e12685fa 100644
--- a/runtime/vm/object.cc
+++ b/runtime/vm/object.cc
@@ -10035,26 +10035,26 @@ bool String::Equals(const Instance& other) const {
 }
 
 
-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.