Fix capturing of for-loop variables

runtime/vm/parser.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/parser.h"
 
 #include "vm/bigint_operations.h"
 #include "vm/class_finalizer.h"
 #include "vm/compiler.h"
 #include "vm/compiler_stats.h"
@@ skipping 4699 matching lines @@
   LocalScope* incr_scope = current_block_->scope;
   if (CurrentToken() != Token::kRPAREN) {
     increment = ParseExprList();
   }
   ExpectToken(Token::kRPAREN);
   const bool parsing_loop_body =  true;
   SequenceNode* body = ParseNestedStatement(parsing_loop_body, NULL);
 
   // Check whether any of the variables in the initializer part of
   // the for statement are captured by a closure. If so, we insert a
-  // node that creates a new Context at the end of the loop body (but
-  // before the increment expression is evaluated).
+  // node that creates a new Context for the loop variable before
+  // the increment expression is evaluated.
   for (int i = 0; i < init_scope->num_variables(); i++) {
     if (init_scope->VariableAt(i)->is_captured() &&
         (init_scope->VariableAt(i)->owner() == init_scope)) {
-      body->Add(new CloneContextNode(for_pos));
+      SequenceNode* incr_sequence = new SequenceNode(incr_pos, incr_scope);
+      incr_sequence->Add(new CloneContextNode(for_pos));
+      if (increment != NULL) {
+        incr_sequence->Add(increment);
+      }
+      increment = incr_sequence;
       break;
     }
   }
   CloseBlock();
   return new ForNode(for_pos,
                      label,
                      NodeAsSequenceNode(init_pos, initializer, init_scope),
                      condition,
                      NodeAsSequenceNode(incr_pos, increment, incr_scope),
                      body);
@@ skipping 3511 matching lines @@
 void Parser::SkipQualIdent() {
   ASSERT(IsIdentifier());
   ConsumeToken();
   if (CurrentToken() == Token::kPERIOD) {
     ConsumeToken();  // Consume the kPERIOD token.
     ExpectIdentifier("identifier expected after '.'");
   }
 }
 
 }  // namespace dart