Try to fix issue #991

Author: vrqq

include/cnl/_impl/num_traits/scale.h

@@ -46,18 +46,6 @@ namespace cnl {
             : _impl::default_scale<Digits, Radix, S> {
     };
 
-    template<int Digits, int Radix, template<typename, typename>
-    class TNUM, typename S, typename Tag>
-    struct scale<Digits, Radix, TNUM<S, Tag>, _impl::enable_if_t<(
-        Digits<0 && cnl::_impl::is_integral<S>::value)>>
-    {
-        CNL_NODISCARD constexpr auto operator()(TNUM<S, Tag> const& s) const
-        -> decltype(s/_impl::power_value<S, -Digits, Radix>())
-        {
-            return s/_impl::power_value<S, -Digits, Radix>();
-        }
-    };
-
     namespace _impl {
         // cnl::_impl::scale - convenience wrapper for cnl::scale
         template<int Digits, int Radix=2, class S>

include/cnl/rounding_integer.h

@@ -71,6 +71,16 @@ namespace cnl {
                     scale<Digits, Radix, Rep>{}(_impl::to_rep(s)));
         }
     };
+    
+    template<int Digits, int Radix, class Rep, class RoundingTag>
+    struct scale<Digits, Radix, _impl::number<Rep, RoundingTag>,
+            _impl::enable_if_t<Digits < 0 && _impl::is_rounding_tag<RoundingTag>::value>> {
+        CNL_NODISCARD constexpr auto operator()(_impl::number<Rep, RoundingTag> const& s) const
+        -> decltype(s/_impl::power_value<Rep, -Digits, Radix>())
+        {
+            return s/_impl::power_value<Rep, -Digits, Radix>();
+        }
+    };
 
     ////////////////////////////////////////////////////////////////////////////////
     // cnl::set_rep<rounding_integer, Rep>

test/unit/scaled_integer/rounding/rounding_scaled_integer.cpp

@@ -90,4 +90,49 @@ namespace {
         DecX num2 = 10.545;
         std::cout<<num1<<" "<<num2<<std::endl;
     }
+
+    TEST(rounding_scaled_integer, 991AssignTest)
+    {
+        using DecX_2 = cnl::scaled_integer<cnl::rounding_integer<long long>, cnl::power<-2, 10>>;
+        using DecX_4 = cnl::scaled_integer<cnl::rounding_integer<long long>, cnl::power<-4, 10>>;
+        
+        DecX_2 n1 = 10.0151;
+        DecX_2 n2 = 10.0249;
+        EXPECT_EQ(n1, n2); // 10.02
+
+        int64_t xn = (int64_t)n1;
+        double  xm = (double)n2;
+        EXPECT_EQ(xn, 10);
+        EXPECT_DOUBLE_EQ(xm, 10.02);
+        
+        static_assert(std::is_same_v<decltype(n1*n2), DecX_4>);
+        EXPECT_EQ(n1*n2, DecX_4{100.4004});
+        EXPECT_DOUBLE_EQ((double)(n1*n2), 100.4004);
+
+        n1 += 0.6;
+        EXPECT_EQ((int)n1, 11);
+
+        n1 += 0.38;
+        EXPECT_EQ(n1, 11);
+
+        xn += n1;
+        xm -= n1;
+    }
+
+    TEST(rounding_scaled_integer, 991CmpTest)
+    {
+        using DecX_2 = cnl::scaled_integer<cnl::rounding_integer<long long>, cnl::power<-2, 10>>;
+        
+        DecX_2 n1;
+        DecX_2 n2 = 10.019;
+        DecX_2 n3{20.029};
+        EXPECT_DOUBLE_EQ((double)n2, 10.02);
+        EXPECT_DOUBLE_EQ((double)n3, 20.03);
+
+        n1 = 3.999; //4.00 instead
+        n3 = DecX_2(8);
+        EXPECT_NE(n1, 3.9899999999999999999999999);
+        EXPECT_EQ(n1, 4.0000000000000000000000001);
+        EXPECT_EQ(n3, 8);
+    }
 }