Await it!

runtime/vm/scopes.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/scopes.h"
 
 #include "vm/object.h"
 #include "vm/stack_frame.h"
 #include "vm/symbols.h"
 
@@ skipping 584 matching lines @@
     LocalScope* owner_scope = new LocalScope(NULL, 0, 0);
     owner_scope->set_context_level(context_scope.ContextLevelAt(i));
     owner_scope->AddVariable(variable);
     outer_scope->AddVariable(variable);  // As alias.
     ASSERT(variable->owner() == owner_scope);
   }
   return outer_scope;
 }
 
 
+void LocalScope::RecursivelyCaptureAllVariables() {
+  bool found = false;
+  for (intptr_t i = 0; i < num_variables(); i++) {
+    if ((VariableAt(i)->name().raw() == Symbols::StackTraceVar().raw()) ||
+        (VariableAt(i)->name().raw() == Symbols::ExceptionVar().raw())) {
+      // Don't capture those variables as their scope of use can not be
+      // interrupted by await. In other words: There is no way to reach an await
+      // in between assigning them a value and reading the value, as these are
+      // just internals to pass along exception states.
+      continue;
+    }
+    found = CaptureVariable(VariableAt(i)->name());
+    VariableAt(i)->set_is_captured();
+    ASSERT(found);
+  }
+  if (sibling() != NULL) { sibling()->RecursivelyCaptureAllVariables(); }
+  if (child() != NULL) { child()->RecursivelyCaptureAllVariables(); }
+}
+
+
+
 RawContextScope* LocalScope::CreateImplicitClosureScope(const Function& func) {
   static const intptr_t kNumCapturedVars = 1;
 
   // Create a ContextScope with space for kNumCapturedVars descriptors.
   const ContextScope& context_scope =
       ContextScope::Handle(ContextScope::New(kNumCapturedVars));
 
   // Create a descriptor for 'this' variable.
   context_scope.SetTokenIndexAt(0, func.token_pos());
   context_scope.SetNameAt(0, Symbols::This());
@@ skipping 33 matching lines @@
     return fixed_parameter_count - (index() - kParamEndSlotFromFp);
   } else {
     // Shift negative indexes so that the lowest one is 0 (they are still
     // non-positive).
     return fixed_parameter_count - (index() - kFirstLocalSlotFromFp);
   }
 }
 
 
 }  // namespace dart