Add Shield around parameters in Rcpp::interfaces (fixes #712)

ChangeLog

@@ -1,3 +1,7 @@
+2017-06-14  JJ Allaire  <jj@rstudio.com>
+
+        * src/attributes.cpp: Add Shield around parameters in Rcpp::interfaces
+
 2017-06-07  Dirk Eddelbuettel  <edd@debian.org>
 
 	* README.md: Use alternates for img.shields.io GPL-2+ badges

inst/NEWS.Rd

@@ -24,6 +24,7 @@
       addressing \ghit{702}).
       \item Automatically register init functions for Rcpp Modules (\ghpr{705}
       addressing \ghit{704}).
+      \item Add Shield around parameters in Rcpp::interfaces (\ghit{712}).
     }
   }
 }

src/attributes.cpp

@@ -2172,7 +2172,7 @@ namespace attributes {
 
                 const std::vector<Argument>& args = function.arguments();
                 for (std::size_t i = 0; i<args.size(); i++) {
-                    ostr() << "Rcpp::wrap(" << args[i].name() << ")";
+                    ostr() << "Shield<SEXP>(Rcpp::wrap(" << args[i].name() << "))";
                     if (i != (args.size()-1))
                         ostr() << ", ";
                 }