Fix Function.end_token_pos() and implement MethodMirror.source getter

runtime/vm/parser.cc

Index: runtime/vm/parser.cc
diff --git a/runtime/vm/parser.cc b/runtime/vm/parser.cc
index 247fbc7f70c8acc5bb4ed2b4059c983d954c397c..3aef333809cd50808c0413c0289c75a881294a2a 100644
--- a/runtime/vm/parser.cc
+++ b/runtime/vm/parser.cc
@@ -2698,14 +2698,17 @@ SequenceNode* Parser::ParseFunc(const Function& func,
     ConsumeToken();
     ParseStatementSequence();
     ExpectToken(Token::kRBRACE);
+    func.set_end_token_pos(TokenPos() - 1);

[hausner, 2013/08/20 17:49:44]

Read the closing brace after setting the end token pos, so you can avoid the - 1
(which is only accidentally correct as we discussed offline).

[Michael Lippautz (Google), 2013/08/21 16:50:03]

Done.

   } else if (CurrentToken() == Token::kARROW) {
     ConsumeToken();
     const intptr_t expr_pos = TokenPos();
     AstNode* expr = ParseExpr(kAllowConst, kConsumeCascades);
     ASSERT(expr != NULL);
     current_block_->statements->Add(new ReturnNode(expr_pos, expr));
+    func.set_end_token_pos(TokenPos());
   } else if (IsLiteral("native")) {
     ParseNativeFunctionBlock(&params, func);

[hausner, 2013/08/20 17:49:44]

Can you refactor the code so that ParseNativeFunctionBlock does not consume the
semicolon? Then, set the end token pos to TokenPos() and read the semicolon
afterwards.

[Michael Lippautz (Google), 2013/08/21 16:50:03]

Done.

+    func.set_end_token_pos(TokenPos() - 1);
   } else if (func.is_external()) {
     // Body of an external method contains a single throw.
     const String& function_name = String::ZoneHandle(func.name());
@@ -5308,8 +5311,6 @@ AstNode* Parser::ParseFunctionStatement(bool is_literal) {
   Array& default_parameter_values = Array::Handle();
   SequenceNode* statements = Parser::ParseFunc(function,
                                                default_parameter_values);
-  ASSERT(is_new_closure || (function.end_token_pos() == (TokenPos() - 1)));
-  function.set_end_token_pos(TokenPos() - 1);
 
   // Now that the local function has formal parameters, lookup the signature
   // class in the current library (but not in its imports) and only create a new