Investigate failing test: Scale/Precision is broken SqlClient (issue 1612 logged)

Dapper NET40/SqlMapper.cs

@@ -4771,10 +4771,7 @@ protected void AddParameters(IDbCommand command, SqlMapper.Identity identity)
                                 p.Size = DbString.DefaultLength;
                             }
                         }
-                        if (param.Size != null)
-                        {
-                            p.Size = param.Size.Value;
-                        }
+                        if (param.Size != null) p.Size = param.Size.Value;
                         if (param.Precision != null) p.Precision = param.Precision.Value;
                         if (param.Scale != null) p.Scale = param.Scale.Value;
                     }
@@ -4782,6 +4779,8 @@ protected void AddParameters(IDbCommand command, SqlMapper.Identity identity)
                     {
                         if (dbType != null) p.DbType = dbType.Value;
                         if (param.Size != null) p.Size = param.Size.Value;
+                        if (param.Precision != null) p.Precision = param.Precision.Value;
+                        if (param.Scale != null) p.Scale = param.Scale.Value;
                         handler.SetValue(p, val ?? DBNull.Value);
                     }
 

Tests/Program.cs

@@ -58,7 +58,11 @@ static void RunPerformanceTests()
 
         static void Main()
         {
-
+#if DNXCORE50
+            Console.WriteLine("CoreCLR");
+#else
+            Console.WriteLine(Environment.Version);
+#endif
 #if DEBUG
             RunTests();
 #else

Tests/Tests.cs

@@ -4337,6 +4337,60 @@ public void Issue261_Decimals()
             c.IsEqualTo(11.884M);
         }
 
+        public void Issue261_Decimals_ADONET_SetViaBaseClass()
+        {
+            Issue261_Decimals_ADONET(true);
+        }
+
+        public void Issue261_Decimals_ADONET_SetViaConcreteClass()
+        {
+            Issue261_Decimals_ADONET(false);
+        }
+        private void Issue261_Decimals_ADONET(bool setPrecisionScaleViaAbstractApi)
+        {
+            try
+            {
+                using (var cmd = connection.CreateCommand())
+                {
+                    cmd.CommandText = "create proc #Issue261Direct @c decimal(10,5) OUTPUT as begin set @c=11.884 end";
+                    cmd.ExecuteNonQuery();
+                }
+            }
+            catch { /* we don't care that it already exists */ }
+
+            using (var cmd = connection.CreateCommand())
+            {
+                cmd.CommandType = CommandType.StoredProcedure;
+                cmd.CommandText = "#Issue261Direct";
+                var c = cmd.CreateParameter();
+                c.ParameterName = "c";
+                c.Direction = ParameterDirection.Output;
+                c.Value = DBNull.Value;
+                c.DbType = DbType.Decimal;
+
+                if (setPrecisionScaleViaAbstractApi)
+                {
+#if DNXCORE50
+                    DbParameter baseParam = c;
+#else
+                    IDbDataParameter baseParam = c;
+#endif
+                    baseParam.Precision = 10;
+                    baseParam.Scale = 5;
+                }
+                else
+                {
+                    c.Precision = 10;
+                    c.Scale = 5;
+                }
+
+                cmd.Parameters.Add(c);
+                cmd.ExecuteNonQuery();
+                decimal value = (decimal)c.Value;
+                value.IsEqualTo(11.884M);
+            }
+        }
+
         public void BasicDecimals()
         {
             var c = connection.Query<decimal>("select @c", new { c = 11.884M }).Single();