forward empty error messages (#312)

Author: kevinushey

ChangeLog

@@ -1,3 +1,8 @@
+2015-06-25  Kevin Ushey  <[email protected]>
+
+        * inst/include/Rcpp/Function.h: catch empty error messages
+        * inst/include/Rcpp/api/meat/Rcpp_eval.h: protect call
+
 2015-06-18  Dirk Eddelbuettel  <[email protected]>
 
         * R/Attributes.R (evalCpp): Add support for plugings argument

inst/include/Rcpp/Function.h

@@ -75,7 +75,8 @@ namespace Rcpp{
         }
 
         SEXP operator()() const {
-            return Rcpp_eval( Rf_lang1( Storage::get__()  ) ) ;
+            Shield<SEXP> call(Rf_lang1(Storage::get__()));
+            return Rcpp_eval(call);
         }
 
         #include <Rcpp/generated/Function__operator.h>

inst/include/Rcpp/api/meat/Rcpp_eval.h

@@ -27,6 +27,7 @@ namespace Rcpp{
         SEXP env;
         SEXP result;
         std::vector<std::string> warnings;
+        bool error_occurred;
         std::string error_message;
     };
 
@@ -80,8 +81,10 @@ namespace Rcpp{
             Shield<SEXP> current_error        ( rcpp_get_current_error() ) ;
             Shield<SEXP> conditionMessageCall (::Rf_lang2(conditionMessageSym, current_error)) ;
             Shield<SEXP> condition_message    (::Rf_eval(conditionMessageCall, R_GlobalEnv)) ;
+            evalCall->error_occurred = true;
             evalCall->error_message = std::string(CHAR(::Rf_asChar(condition_message)));
         } else {
+            evalCall->error_occurred = false;
             evalCall->result = res;
         }
     }
@@ -102,7 +105,7 @@ namespace Rcpp{
 
         // handle error or result if it completed, else throw interrupt
         if (completed) {
-            if (!call.error_message.empty())
+            if (call.error_occurred)
                 throw eval_error(call.error_message);
             else
                 return call.result;