fix functions/sum.h

Author: Enchufa2

inst/include/Rcpp/sugar/functions/sum.h

@@ -2,7 +2,8 @@
 //
 // sum.h: Rcpp R/C++ interface class library -- sum
 //
-// Copyright (C) 2010 - 2011 Dirk Eddelbuettel and Romain Francois
+// Copyright (C) 2010 - 2025 Dirk Eddelbuettel and Romain Francois
+// Copyright (C) 2026        Dirk Eddelbuettel, Romain Francois and Iñaki Ucar
 //
 // This file is part of Rcpp.
 //
@@ -42,7 +43,7 @@ class Sum : public Lazy< typename Rcpp::traits::storage_type<RTYPE>::type , Sum<
 		    current = object[i] ;
 		    if( Rcpp::traits::is_na<RTYPE>(current) )
 		        return Rcpp::traits::get_na<RTYPE>() ;
-		    result += current ;
+		    result = RCPP_SAFE_ADD(result, current);
 		}
 		return result ;
 	}
@@ -84,7 +85,7 @@ class Sum<RTYPE,false,T> : public Lazy< typename Rcpp::traits::storage_type<RTYP
 		STORAGE result = 0 ;
 		R_xlen_t n = object.size() ;
 		for( R_xlen_t i=0; i<n; i++){
-		    result += object[i] ;
+		    result = RCPP_SAFE_ADD(result, object[i]);
 		}
 		return result ;
 	}

inst/tinytest/cpp/sugar.cpp

@@ -604,7 +604,12 @@ List runit_log1p( NumericVector xx){
 }
 
 // [[Rcpp::export]]
-double runit_sum( NumericVector xx){
+double runit_sum_nv( NumericVector xx){
+    return sum( xx ) ;
+}
+
+// [[Rcpp::export]]
+int runit_sum_iv( IntegerVector xx){
     return sum( xx ) ;
 }
 

inst/tinytest/test_sugar.R

@@ -645,14 +645,23 @@ expect_equal(fx(10:6,5:1),
                   VP = psigamma( 10:6, 5 )))
 
 
-#    test.sugar.sum <- function(){
-fx <- runit_sum
+#    test.sugar.sum_nv <- function(){
+fx <- runit_sum_nv
 x <- rnorm( 10 )
 expect_equal( fx(x), sum(x) )
 x[4] <- NA
 expect_equal( fx(x), sum(x) )
 
 
+#    test.sugar.sum_iv <- function() {
+expect_error(runit_sum_iv(c(2, .Machine$integer.max)), "overflow")
+fx <- runit_sum_iv
+x <- as.integer(rpois(10, 5))
+expect_equal(fx(x), sum(x))
+x[4] <- NA
+expect_equal(fx(x), sum(x))
+
+
 #    test.sugar.cumsum_nv <- function(){
 fx <- runit_cumsum_nv
 x <- rnorm(10)