Modify approach to copying attributes.

Make use of the fact set__() already does a conversion, and just use
that. This has the benefit that it works with push_back(DataFrame), as
well as push_back(Vector), and also handles adding vectors of different
lengths properly.

Author: waltersom

inst/include/Rcpp/DataFrame.h

@@ -85,38 +85,26 @@ namespace Rcpp{
 
 	template <typename T>
         void push_back( const T& object){
-            R_xlen_t NewSize = std::max(object.size(), static_cast<R_xlen_t>(nrow()));
             Parent::push_back(object);
-            IntegerVector RowNames = Range(1, NewSize);
-            Rf_setAttrib(Parent::get__(), R_RowNamesSymbol, RowNames);
-            Rf_setAttrib(Parent::get__(), R_ClassSymbol, Rf_mkString("data.frame"));
+            set__(Parent::get__());
         }
 
         template <typename T>
         void push_back( const T& object, const std::string& name ){
-            R_xlen_t NewSize = std::max(object.size(), static_cast<R_xlen_t>(nrow()));
             Parent::push_back(object, name);
-            IntegerVector RowNames = Range(1, NewSize);
-            Rf_setAttrib(Parent::get__(), R_RowNamesSymbol, RowNames);
-            Rf_setAttrib(Parent::get__(), R_ClassSymbol, Rf_mkString("data.frame"));
+            set__(Parent::get__());
         }
 
         template <typename T>
         void push_front( const T& object){
-            R_xlen_t NewSize = std::max(object.size(), static_cast<R_xlen_t>(nrow()));
             Parent::push_front(object);
-            IntegerVector RowNames = Range(1, NewSize);
-            Rf_setAttrib(Parent::get__(), R_RowNamesSymbol, RowNames);
-            Rf_setAttrib(Parent::get__(), R_ClassSymbol, Rf_mkString("data.frame"));
+            set__(Parent::get__());
         }
 
         template <typename T>
         void push_front( const T& object, const std::string& name){
-            R_xlen_t NewSize = std::max(object.size(), static_cast<R_xlen_t>(nrow()));
             Parent::push_front(object, name);
-            IntegerVector RowNames = Range(1, NewSize);
-            Rf_setAttrib(Parent::get__(), R_RowNamesSymbol, RowNames);
-            Rf_setAttrib(Parent::get__(), R_ClassSymbol, Rf_mkString("data.frame"));
+            set__(Parent::get__());
         }
 
         // Offer multiple variants to accomodate both old interface here and signatures in other classes

inst/tinytest/cpp/DataFrame.cpp

@@ -130,3 +130,30 @@ DataFrame DataFrame_PushFrontUnnamed(){
     df.push_front(v);
     return df;
 }
+
+// [[Rcpp::export]]
+DataFrame DataFrame_PushFrontDataFrame(){
+  NumericVector u(2);
+  NumericVector v(2);
+  NumericVector w(2);
+  NumericVector x(2);
+
+  DataFrame df1 = DataFrame::create(_["u"] = u, _["v"] = v);
+  DataFrame df2 = DataFrame::create(_["w"] = w, _["x"] = x);
+  df1.push_front(df2);
+  return df1;
+}
+
+// [[Rcpp::export]]
+DataFrame DataFrame_PushBackDataFrame(){
+  NumericVector u(2);
+  NumericVector v(2);
+  NumericVector w(2);
+  NumericVector x(2);
+
+  DataFrame df1 = DataFrame::create(_["u"] = u, _["v"] = v);
+  DataFrame df2 = DataFrame::create(_["w"] = w, _["x"] = x);
+  df1.push_back(df2);
+  return df1;
+}
+

inst/tinytest/test_dataframe.R

@@ -77,7 +77,7 @@ expect_true( is.data.frame( DataFrame_PushBackNamed() ) )
 expect_equal( DataFrame_PushBackNamed(), df )
 
 #    test.DataFrame.PushBackUnamed <- function(){
-df <- data.frame( u = c(0, 0), c(0, 0), fix.empty.names = FALSE )
+df <- data.frame( u = c(0, 0), c(0, 0) )
 expect_true( is.data.frame( DataFrame_PushBackUnnamed() ) )
 expect_equal( DataFrame_PushBackUnnamed(), df )
 
@@ -87,6 +87,17 @@ expect_true( is.data.frame( DataFrame_PushFrontNamed() ) )
 expect_equal( DataFrame_PushFrontNamed(), df )
 
 #    test.DataFrame.PushFrontUnnamed <- function(){
-df <- data.frame( c(0, 0), u = c(0, 0), fix.empty.names = FALSE )
+df <- data.frame( c(0, 0), u = c(0, 0) )
 expect_true( is.data.frame( DataFrame_PushFrontUnnamed() ) )
 expect_equal( DataFrame_PushFrontUnnamed(), df )
+
+
+#    test.DataFrame.PushFrontDataFrame <- function(){
+df <- data.frame( w = c(0, 0), x = c(0, 0), u = c(0, 0), v = c(0, 0) )
+expect_true( is.data.frame( DataFrame_PushFrontDataFrame() ) )
+expect_equal( DataFrame_PushFrontDataFrame(), df )
+
+#    test.DataFrame.PushBackDataFrame <- function(){
+df <- data.frame( u = c(0, 0), v = c(0, 0), w = c(0, 0), x = c(0, 0) )
+expect_true( is.data.frame( DataFrame_PushBackDataFrame() ) )
+expect_equal( DataFrame_PushBackDataFrame(), df )