Fix scoping of catch clause 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 "lib/invocation_mirror.h"
 #include "platform/utils.h"
 #include "vm/ast.h"
 #include "vm/bootstrap.h"
@@ skipping 6857 matching lines @@
         // TODO(hausner): Make implicit type be StackTrace, not dynamic.
         stack_trace_param.type = Type::DynamicType();
         stack_trace_param.token_pos = TokenPos();
         stack_trace_param.name = ExpectIdentifier("identifier expected");
       }
       ExpectToken(Token::kRPAREN);
     }
 
     // Parse the individual catch handler code and add an unconditional JUMP
     // to the end of the try block.
-    ExpectToken(Token::kLBRACE);
-    OpenBlock();
+    OpenBlock();  // Block for the exception and stack trace variables.
     AddCatchParametersToScope(&exception_param, &stack_trace_param,
                               current_block_->scope);
 
     if (exception_param.var != NULL) {
       // Generate code to load the exception object (:exception_var) into
       // the exception variable specified in this block.
       ASSERT(exception_var != NULL);
       current_block_->statements->Add(
           new StoreLocalNode(catch_pos, exception_param.var,
                              new LoadLocalNode(catch_pos, exception_var)));
     }
     if (stack_trace_param.var != NULL) {
       // A stack trace variable is specified in this block, so generate code
       // to load the stack trace object (:stack_trace_var) into the stack
       // trace variable specified in this block.
       needs_stack_trace = true;
       ArgumentListNode* no_args = new ArgumentListNode(catch_pos);
       ASSERT(stack_trace_var != NULL);
       current_block_->statements->Add(
           new StoreLocalNode(catch_pos, stack_trace_param.var,
                              new LoadLocalNode(catch_pos, stack_trace_var)));
       current_block_->statements->Add(
           new InstanceCallNode(
               catch_pos,
               new LoadLocalNode(catch_pos, stack_trace_param.var),
               Library::PrivateCoreLibName(Symbols::_setupFullStackTrace()),
               no_args));
     }
 
-    ParseStatementSequence();  // Parse the catch handler code.
-    current_block_->statements->Add(
+    // Parse the catch handler code.
+    if (CurrentToken() != Token::kLBRACE) {
+      ErrorMsg("'{' expected");
+    }
+    SequenceNode* catch_block = ParseNestedStatement(false, NULL);
+    catch_block->Add(
         new JumpNode(catch_pos, Token::kCONTINUE, end_catch_label));
-    SequenceNode* catch_handler = CloseBlock();
-    ExpectToken(Token::kRBRACE);
 
     const bool is_bad_type = exception_param.type.IsMalformed() ||
                              exception_param.type.IsMalbounded();
     if (!is_bad_type && !exception_param.type.IsDynamicType()) {
       // Has a type specification that is not malformed or malbounded.
       // Now form an 'if type check' as an exception type exists in the
       // catch specifier.
       if (!exception_param.type.IsInstantiated() &&
           (current_block_->scope->function_level() > 0)) {
         // Make sure that the instantiator is captured.
         CaptureInstantiator();
       }
       TypeNode* exception_type = new TypeNode(catch_pos, exception_param.type);
       AstNode* exception_value = new LoadLocalNode(catch_pos, exception_var);
       if (!exception_type->type().IsInstantiated()) {
         EnsureExpressionTemp();
       }
       AstNode* type_cond_expr = new ComparisonNode(
           catch_pos, Token::kIS, exception_value, exception_type);
       current_block_->statements->Add(
-          new IfNode(catch_pos, type_cond_expr, catch_handler, NULL));
+          new IfNode(catch_pos, type_cond_expr, catch_block, NULL));
 
       // Do not add uninstantiated types (e.g. type parameter T or generic
       // type List<T>), since the debugger won't be able to instantiate it
       // when walking the stack.  This means that the debugger is not able
       // to determine whether an exception is caught if the catch clause
       // uses generic types.  It will report the exception as uncaught when
       // in fact it might be caught and handled when we unwind the stack.
       if (exception_param.type.IsInstantiated()) {
         handler_types.Add(exception_param.type);
       }
     } else {
       if (is_bad_type) {
         current_block_->statements->Add(ThrowTypeError(catch_pos,
                                                        exception_param.type));
         // We still add the dead code below to satisfy the code generator.
       }
       // No exception type exists in the catch specifier so execute the
       // catch handler code unconditionally.
-      current_block_->statements->Add(catch_handler);
+      current_block_->statements->Add(catch_block);
       generic_catch_seen = true;
       // This catch clause will handle all exceptions. We can safely forget
       // all previous catch clause types.
       handler_types.SetLength(0);
       handler_types.Add(exception_param.type);
     }
+    // Add this individual catch handler to the catch handlers list.
+    SequenceNode* catch_clause = CloseBlock();
+    current_block_->statements->Add(catch_clause);
   }
   SequenceNode* catch_handler_list = CloseBlock();
   TryBlocks* inner_try_block = PopTryBlock();
   const intptr_t try_index = inner_try_block->try_index();
   TryBlocks* outer_try_block = try_blocks_list_;
   const intptr_t outer_try_index = (outer_try_block != NULL)
       ? outer_try_block->try_index()
       : CatchClauseNode::kInvalidTryIndex;
 
   // Finally parse the 'finally' block.
@@ skipping 3768 matching lines @@
 void Parser::SkipQualIdent() {
   ASSERT(IsIdentifier());
   ConsumeToken();
   if (CurrentToken() == Token::kPERIOD) {
     ConsumeToken();  // Consume the kPERIOD token.
     ExpectIdentifier("identifier expected after '.'");
   }
 }
 
 }  // namespace dart