support for empty lists

Dapper/SqlMapper.cs

@@ -375,10 +375,17 @@ public static void PackListParameters(IDbCommand command, string namePrefix, obj
                     command.Parameters.Add(listParam);
                 }
 
-                command.CommandText = command.CommandText.Replace(namePrefix,
-                    "(" + string.Join(
-                        ",", Enumerable.Range(1, count).Select(i => namePrefix + i.ToString())
-                    ) + ")");
+                if (count == 0)
+                {
+                    command.CommandText = command.CommandText.Replace(namePrefix, "(SELECT NULL WHERE 1 = 0)");
+                }
+                else
+                {
+                    command.CommandText = command.CommandText.Replace(namePrefix,
+                        "(" + string.Join(
+                            ",", Enumerable.Range(1, count).Select(i => namePrefix + i.ToString())
+                        ) + ")");
+                }
             }
 
         }

Tests/Tests.cs

@@ -154,6 +154,9 @@ public void TestStringList()
         {
             connection.Query<string>("select * from (select 'a' as x union all select 'b' union all select 'c') as T where x in @strings", new {strings = new[] {"a","b","c"}})
                 .IsSequenceEqualTo(new[] {"a","b","c"});
+
+             connection.Query<string>("select * from (select 'a' as x union all select 'b' union all select 'c') as T where x in @strings", new { strings = new string[0] })
+	                .IsSequenceEqualTo(new string[0]);
         }
 
         public void TestExecuteCommand()