Delay Class parsing until the class is actually used.

runtime/vm/dart_api_impl.cc

 // Copyright (c) 2013, 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 "include/dart_api.h"
 
 #include "platform/assert.h"
 #include "vm/bigint_operations.h"
 #include "vm/class_finalizer.h"
 #include "vm/compiler.h"
@@ skipping 3033 matching lines @@
     return target;
   }
 
   const GrowableObjectArray& names =
       GrowableObjectArray::Handle(isolate, GrowableObjectArray::New());
   Function& func = Function::Handle();
   String& name = String::Handle();
 
   if (obj.IsClass()) {
     const Class& cls = Class::Cast(obj);
+    const Error& error = Error::Handle(isolate, cls.EnsureIsFinalized(isolate));
+    if (!error.IsNull()) {
+      return Api::NewHandle(isolate, error.raw());
+    }
     const Array& func_array = Array::Handle(cls.functions());
 
     // Some special types like 'dynamic' have a null functions list.
     if (!func_array.IsNull()) {
       for (intptr_t i = 0; i < func_array.Length(); ++i) {
         func ^= func_array.At(i);
 
         // Skip implicit getters and setters.
         if (func.kind() == RawFunction::kImplicitGetter ||
             func.kind() == RawFunction::kImplicitSetter ||
@@ skipping 320 matching lines @@
     return target;
   }
 
   const GrowableObjectArray& names =
       GrowableObjectArray::Handle(isolate, GrowableObjectArray::New());
   Field& field = Field::Handle(isolate);
   String& name = String::Handle(isolate);
 
   if (obj.IsClass()) {
     const Class& cls = Class::Cast(obj);
+    const Error& error = Error::Handle(isolate, cls.EnsureIsFinalized(isolate));
+    if (!error.IsNull()) {
+      return Api::NewHandle(isolate, error.raw());
+    }
     const Array& field_array = Array::Handle(cls.fields());
 
     // Some special types like 'dynamic' have a null fields list.
     //
     // TODO(turnidge): Fix 'dynamic' so that it does not have a null
     // fields list.  This will have to wait until the empty array is
     // allocated in the vm isolate.
     if (!field_array.IsNull()) {
       for (intptr_t i = 0; i < field_array.Length(); ++i) {
         field ^= field_array.At(i);
@@ skipping 1468 matching lines @@
   }
   {
     NoGCScope no_gc;
     RawObject* raw_obj = obj.raw();
     isolate->heap()->SetPeer(raw_obj, peer);
   }
   return Api::Success(isolate);
 }
 
 }  // namespace dart