Allow String.fromCharCodes to work directly on a GrowableObjectArray.

runtime/lib/string.cc

 // Copyright (c) 2011, 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/bootstrap_natives.h"
 
 #include "vm/exceptions.h"
 #include "vm/native_entry.h"
 #include "vm/object.h"
 #include "vm/symbols.h"
 #include "vm/unicode.h"
 
 namespace dart {
 
 DEFINE_NATIVE_ENTRY(StringBase_createFromCodePoints, 1) {
-  GET_NON_NULL_NATIVE_ARGUMENT(Array, a, arguments->NativeArgAt(0));
+  GET_NON_NULL_NATIVE_ARGUMENT(Instance, list, arguments->NativeArgAt(0));
+  bool is_growable = list.IsGrowableObjectArray();
+  if (!is_growable && !list.IsArray()) {
+    const Array& args = Array::Handle(Array::New(1));
+    args.SetAt(0, list);
+    Exceptions::ThrowByType(Exceptions::kArgument, args);
+  }
   // TODO(srdjan): Check that parameterized type is an int.
+  Array& a = Array::Handle(
+      is_growable ? GrowableObjectArray::Cast(list).data()
+                 : Array::Cast(list).raw());
+  intptr_t array_len = is_growable ? GrowableObjectArray::Cast(list).Length()
+                                   : a.Length();

[siva, 2013/03/14 15:56:02]

I would structure this code as:
if (!list.IsGrowableObjectArray() && ! list.IsArray()) {
  ...
  ...
}
Array& a = Array::Handle();
intptr_t array_len = 0;
if (list.IsGrowableObjectArray()) {
  const GrowableObjectArray& ga = GrowableObjectArray::Cast(list);
  a ^= ga.data();
  array_len = ga.Length();
} else {
  a ^= Array::Cast(list).raw();
  array_length = a.Length();
}
....
....

[Lasse Reichstein Nielsen, 2013/03/15 06:58:40]

Much better. Done!

+
   Zone* zone = isolate->current_zone();
-  intptr_t array_len = a.Length();
 
   // Unbox the array and determine the maximum element width.
   bool is_one_byte_string = true;
   intptr_t utf16_len = array_len;
   int32_t* utf32_array = zone->Alloc<int32_t>(array_len);
   Object& index_object = Object::Handle(isolate);
   for (intptr_t i = 0; i < array_len; i++) {
     index_object = a.At(i);
     if (!index_object.IsSmi()) {
       const Array& args = Array::Handle(Array::New(1));
@@ skipping 11 matching lines @@
         }
       }
     }
     utf32_array[i] = value;
   }
   if (is_one_byte_string) {
     return OneByteString::New(utf32_array, array_len, Heap::kNew);
   }
   return TwoByteString::New(utf16_len, utf32_array, array_len, Heap::kNew);
 }
 

[siva, 2013/03/14 15:56:02]

Why remove the blank line here, we normally have 2 blank lines after a function.

[Lasse Reichstein Nielsen, 2013/03/15 06:58:40]

No reason. I moved the body of the method into a helper function at some point,
and then back again. Must have lost a line along the way.

-
 DEFINE_NATIVE_ENTRY(StringBase_substringUnchecked, 3) {
   const String& receiver = String::CheckedHandle(arguments->NativeArgAt(0));
   GET_NON_NULL_NATIVE_ARGUMENT(Smi, start_obj, arguments->NativeArgAt(1));
   GET_NON_NULL_NATIVE_ARGUMENT(Smi, end_obj, arguments->NativeArgAt(2));
 
   intptr_t start = start_obj.Value();
   intptr_t end = end_obj.Value();
   return String::SubString(receiver, start, (end - start));
 }
 
@@ skipping 151 matching lines @@
       ? String::Handle(OneByteString::New(length_value, Heap::kNew))
       : String::Handle(TwoByteString::New(length_value, Heap::kNew));
   NoGCScope no_gc;
 
   uint16_t* data_position = reinterpret_cast<uint16_t*>(codeUnits.ByteAddr(0));
   String::Copy(result, 0, data_position, length_value);
   return result.raw();
 }
 
 }  // namespace dart