vm-service: Add optional 'scope' parameter to 'evaluate' and 'evaluateInFrame'.

runtime/vm/debugger.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/debugger.h"
 
 #include "include/dart_api.h"
 
 #include "platform/address_sanitizer.h"
 
@@ skipping 1272 matching lines @@
 static bool IsSyntheticVariableName(const String& var_name) {
   return (var_name.Length() >= 1) && (var_name.CharAt(0) == ':');
 }
 
 
 static bool IsPrivateVariableName(const String& var_name) {
   return (var_name.Length() >= 1) && (var_name.CharAt(0) == '_');
 }
 
 
-RawObject* ActivationFrame::Evaluate(const String& expr) {
+RawObject* ActivationFrame::Evaluate(const String& expr,
+                                     const GrowableObjectArray& param_names,
+                                     const GrowableObjectArray& param_values) {
   GetDescIndices();
-  const GrowableObjectArray& param_names =
-      GrowableObjectArray::Handle(GrowableObjectArray::New());
-  const GrowableObjectArray& param_values =
-      GrowableObjectArray::Handle(GrowableObjectArray::New());
   String& name = String::Handle();
+  String& existing_name = String::Handle();
   Object& value = Instance::Handle();
   intptr_t num_variables = desc_indices_.length();
   for (intptr_t i = 0; i < num_variables; i++) {
     TokenPosition ignore;
     VariableAt(i, &name, &ignore, &ignore, &ignore, &value);
     if (!name.Equals(Symbols::This()) && !IsSyntheticVariableName(name)) {
       if (IsPrivateVariableName(name)) {
         name = String::ScrubName(name);
       }
-      param_names.Add(name);
-      param_values.Add(value);
+      bool conflict = false;
+      for (intptr_t j = 0; j < param_names.Length(); j++) {
+        existing_name ^= param_names.At(j);
+        if (name.Equals(existing_name)) {
+          conflict = true;
+          break;
+        }
+      }
+      // If local has the same name as a binding in the incoming scope, prefer
+      // the one from the incoming scope, since it is logically a child scope
+      // of the activation's current scope.
+      if (!conflict) {
+        param_names.Add(name);
+        param_values.Add(value);
+      }
     }
   }
 
   if (function().is_static()) {
     const Class& cls = Class::Handle(function().Owner());
     return cls.Evaluate(expr, Array::Handle(Array::MakeArray(param_names)),
                         Array::Handle(Array::MakeArray(param_values)));
   } else {
     const Object& receiver = Object::Handle(GetReceiver());
     const Class& method_cls = Class::Handle(function().origin());
@@ skipping 3095 matching lines @@
 
 void Debugger::RegisterCodeBreakpoint(CodeBreakpoint* bpt) {
   ASSERT(bpt->next() == NULL);
   bpt->set_next(code_breakpoints_);
   code_breakpoints_ = bpt;
 }
 
 #endif  // !PRODUCT
 
 }  // namespace dart