factor levels

DESCRIPTION

@@ -1,8 +1,8 @@
 Package: geometries
 Type: Package
 Title: Convert Between R Objects and Geometric Structures
-Date: 2023-06-22
-Version: 0.2.3
+Date: 2024-01-03
+Version: 0.2.4
 Authors@R: c(
     person("David", "Cooley", ,"[email protected]", role = c("aut", "cre"))
     )

NEWS.md

@@ -1,4 +1,8 @@
 
+# 0.2.4
+
+* factor levels remain [sfheaders issue 89](https://github.com/dcooley/sfheaders/issues/89)
+
 # 0.2.2
 
 * removed C++ system requirements

inst/include/geometries/utils/unique/unique_sort.hpp

@@ -2,6 +2,7 @@
 #define R_GEOMETRIES_UTILS_UNIQUE_SORT_H
 
 #include <Rcpp.h>
+#include "geometries/utils/attributes/attributes.hpp"
 
 namespace geometries {
 namespace utils {
@@ -35,6 +36,20 @@ namespace utils {
       return sexp_unique< double, REALSXP >( s2 );
     }
     case INTSXP: {
+      // issue 89 (sfheaders - https://github.com/dcooley/sfheaders/issues/89)
+      if( Rf_isFactor(s2) ) {
+        Rcpp::IntegerVector iv = Rcpp::as< Rcpp::IntegerVector >( s2 );
+        Rcpp::List attributes = Rcpp::List::create(
+          Rcpp::_["levels"] = iv.attr("levels"),
+          Rcpp::_["class"] = iv.attr("class")
+        );
+
+        SEXP res = sexp_unique< int, INTSXP >( s2 );
+        geometries::utils::attach_attributes( res, attributes  );
+        return res;
+      }
+
+
       return sexp_unique< int, INTSXP >( s2 );
     }
     case STRSXP: {

inst/tinytest/test_unique.R

@@ -15,3 +15,9 @@ expect_equal( geometries:::.test_unique_sort( c(1L,3L,3L,2L) ), c(1L,3L,2L) )
 expect_equal( geometries:::.test_unique_sort( c(1,3,3,2) ), c(1,3,2) )
 expect_equal( geometries:::.test_unique_sort( c(T,F,F,T) ), c(T,F) )
 
+## Sorting factor - levels remain
+f <- as.factor(c(1,2,3))
+expect_equal(geometries:::.test_unique_sort(f), f)
+
+df <- data.frame(fact = f)
+expect_equal(geometries:::.test_unique_ids(df, 0L), f)