Prevent mutation of final variables

runtime/vm/ast.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/ast.h"
 #include "vm/compiler.h"
 #include "vm/dart_entry.h"
 #include "vm/isolate.h"
 #include "vm/object_store.h"
 #include "vm/resolver.h"
@@ skipping 297 matching lines @@
     return NULL;
   }
   if (HasPseudo()) {
     return NULL;
   }
   return new StoreLocalNode(token_pos(), &local(), rhs);
 }
 
 
 AstNode* LoadStaticFieldNode::MakeAssignmentNode(AstNode* rhs) {
+  if (field().is_final()) {
+    return NULL;
+  }
   return new StoreStaticFieldNode(token_pos(), field(), rhs);
 }
 
 
 AstNode* InstanceGetterNode::MakeAssignmentNode(AstNode* rhs) {
   return new InstanceSetterNode(token_pos(), receiver(), field_name(), rhs);
 }
 
 
 AstNode* LoadIndexedNode::MakeAssignmentNode(AstNode* rhs) {
@@ skipping 27 matching lines @@
     if (!setter.IsNull()) {
       return new StaticSetterNode(token_pos(), NULL, cls(), field_name(), rhs);
     }
     // Could not find a static setter. Look for a field.
     // Access to a lazily initialized static field that has not yet been
     // initialized is compiled to a static implicit getter.
     // A setter may not exist for such a field.
     const Field& field =
         Field::ZoneHandle(cls().LookupStaticField(field_name()));
     if (!field.IsNull()) {
+      if (field.is_final()) {
+        return NULL;
+      }
 #if defined(DEBUG)
       const String& getter_name =
           String::Handle(Field::GetterName(field_name()));
       const Function& getter =
           Function::ZoneHandle(cls().LookupStaticFunction(getter_name));
       ASSERT(!getter.IsNull() &&
              (getter.kind() == RawFunction::kConstImplicitGetter));
 #endif
       return new StoreStaticFieldNode(token_pos(), field, rhs);
     }
@@ skipping 46 matching lines @@
   if (result.IsError() || result.IsNull()) {
     // TODO(turnidge): We could get better error messages by returning
     // the Error object directly to the parser.  This will involve
     // replumbing all of the EvalConstExpr methods.
     return NULL;
   }
   return &Instance::ZoneHandle(Instance::Cast(result).raw());
 }
 
 }  // namespace dart