From bd385f7377adda2919369040f855286dbedb8dc7 Mon Sep 17 00:00:00 2001
From: rbock <rbock@eudoxos.de>
Date: Sat, 3 Oct 2015 17:00:53 +0200
Subject: [PATCH] Added check if all selected columns are aggregates if
 group_by is present

---
 include/sqlpp11/group_by.h           |  3 ++
 include/sqlpp11/select_column_list.h | 19 +++++++++++-
 include/sqlpp11/statement.h          |  6 ++++
 include/sqlpp11/type_traits.h        | 34 +++++++++++++++++++++
 tests/Aggregates.cpp                 | 45 ++++++++++++++++++++++++++++
 tests/CMakeLists.txt                 |  1 +
 tests/SelectType.cpp                 |  2 +-
 7 files changed, 108 insertions(+), 2 deletions(-)
 create mode 100644 tests/Aggregates.cpp

diff --git a/include/sqlpp11/group_by.h b/include/sqlpp11/group_by.h
index 7bd4c296..df168583 100644
--- a/include/sqlpp11/group_by.h
+++ b/include/sqlpp11/group_by.h
@@ -75,6 +75,9 @@ namespace sqlpp
     using _nodes = detail::type_vector<Expressions...>;
 
     using _is_dynamic = is_database<Database>;
+    using _provided_aggregates = typename std::conditional<_is_dynamic::value,
+                                                           detail::type_set<>,
+                                                           detail::make_type_set_t<Expressions...>>::type;
 
     // Data
     using _data_t = group_by_data_t<Database, Expressions...>;
diff --git a/include/sqlpp11/select_column_list.h b/include/sqlpp11/select_column_list.h
index 5322c103..7a90bdef 100644
--- a/include/sqlpp11/select_column_list.h
+++ b/include/sqlpp11/select_column_list.h
@@ -168,6 +168,17 @@ namespace sqlpp
     }
   };
 
+  struct assert_aggregates_t
+  {
+    using type = std::false_type;
+
+    template <typename T = void>
+    static void _()
+    {
+      static_assert(wrong_t<T>::value, "not all columns are made of aggregates, despite group_by or similar");
+    }
+  };
+
   // SELECTED COLUMNS
   template <typename Database, typename... Columns>
   struct select_column_list_t
@@ -262,10 +273,16 @@ namespace sqlpp
         return t.selected_columns;
       }
 
-      using _consistency_check =
+      using _column_check =
           typename std::conditional<Policies::template _no_unknown_tables<select_column_list_t>::value,
                                     consistent_t,
                                     assert_no_unknown_tables_in_selected_columns_t>::type;
+
+      using _aggregate_check = typename std::conditional<Policies::template _no_unknown_aggregates<Columns...>::value,
+                                                         consistent_t,
+                                                         assert_aggregates_t>::type;
+
+      using _consistency_check = detail::get_first_if<is_inconsistent_t, consistent_t, _column_check, _aggregate_check>;
     };
 
     // Result methods
diff --git a/include/sqlpp11/statement.h b/include/sqlpp11/statement.h
index cf4e5c9d..b8e48769 100644
--- a/include/sqlpp11/statement.h
+++ b/include/sqlpp11/statement.h
@@ -103,12 +103,18 @@ namespace sqlpp
       using _all_provided_tables = detail::make_joined_set_t<provided_tables_of<Policies>...>;
       using _all_provided_outer_tables = detail::make_joined_set_t<provided_outer_tables_of<Policies>...>;
       using _all_extra_tables = detail::make_joined_set_t<extra_tables_of<Policies>...>;
+      using _all_provided_aggregates = detail::make_joined_set_t<provided_aggregates_of<Policies>...>;
 
       using _known_tables = detail::make_joined_set_t<_all_provided_tables, _all_extra_tables>;
 
       template <typename Expression>
       using _no_unknown_tables = detail::is_subset_of<required_tables_of<Expression>, _known_tables>;
 
+      template <typename... Expressions>
+      using _no_unknown_aggregates =
+          logic::any_t<_all_provided_aggregates::size::value == 0,
+                       logic::all_t<is_aggregate_expression_t<_all_provided_aggregates, Expressions>::value...>::value>;
+
       template <template <typename> class Predicate>
       using any_t = logic::any_t<Predicate<Policies>::value...>;
 
diff --git a/include/sqlpp11/type_traits.h b/include/sqlpp11/type_traits.h
index 7ce3e9af..fc4de04a 100644
--- a/include/sqlpp11/type_traits.h
+++ b/include/sqlpp11/type_traits.h
@@ -195,6 +195,7 @@ namespace sqlpp
   SQLPP_RECURSIVE_TRAIT_SET_GENERATOR(provided_tables)
   SQLPP_RECURSIVE_TRAIT_SET_GENERATOR(provided_outer_tables)
   SQLPP_RECURSIVE_TRAIT_SET_GENERATOR(extra_tables)
+  SQLPP_RECURSIVE_TRAIT_SET_GENERATOR(provided_aggregates)
 
 #define SQLPP_RECURSIVE_TRAIT_GENERATOR(trait)                                                        \
   namespace detail                                                                                    \
@@ -221,6 +222,38 @@ namespace sqlpp
   SQLPP_RECURSIVE_TRAIT_GENERATOR(can_be_null)
   SQLPP_RECURSIVE_TRAIT_GENERATOR(contains_aggregate_function)
 
+  namespace detail
+  {
+    template <typename KnownAggregates, typename T, typename Leaf = void>
+    struct is_aggregate_expression_impl
+    {
+      using type = typename is_aggregate_expression_impl<KnownAggregates, typename T::_nodes>::type;
+    };
+    template <typename KnownAggregates, typename T>
+    struct is_aggregate_expression_impl<
+        KnownAggregates,
+        T,
+        typename std::enable_if<std::is_class<typename T::_is_aggregate_expression>::value>::type>
+    {
+      using type = typename T::_is_aggregate_expression;
+    };
+    template <typename KnownAggregates, typename T>
+    struct is_aggregate_expression_impl<KnownAggregates,
+                                        T,
+                                        typename std::enable_if<detail::is_element_of<T, KnownAggregates>::value>::type>
+    {
+      using type = std::true_type;
+    };
+    template <typename KnownAggregates, typename... Nodes>
+    struct is_aggregate_expression_impl<KnownAggregates, type_vector<Nodes...>, void>
+    {
+      using type =
+          logic::all_t<sizeof...(Nodes) != 0, is_aggregate_expression_impl<KnownAggregates, Nodes>::type::value...>;
+    };
+  }
+  template <typename KnownAggregates, typename T>
+  using is_aggregate_expression_t = typename detail::is_aggregate_expression_impl<KnownAggregates, T>::type;
+
   namespace detail
   {
     template <typename T, typename Leaf = void>
@@ -259,6 +292,7 @@ namespace sqlpp
   {
     using _nodes = detail::type_vector<>;
     using _contains_aggregate_function = std::true_type;
+    using _is_aggregate_expression = std::true_type;
   };
 
   template <typename NameProvider, typename Member>
diff --git a/tests/Aggregates.cpp b/tests/Aggregates.cpp
new file mode 100644
index 00000000..2c2b71f3
--- /dev/null
+++ b/tests/Aggregates.cpp
@@ -0,0 +1,45 @@
+/*
+ * Copyright (c) 2013-2015, Roland Bock
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ *  * Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
+ * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <iostream>
+#include "Sample.h"
+#include "MockDb.h"
+#include <sqlpp11/alias_provider.h>
+#include <sqlpp11/select.h>
+#include <sqlpp11/functions.h>
+#include <sqlpp11/connection.h>
+
+int Aggregates(int, char**)
+{
+  MockDb db = {};
+  MockDb::_serializer_context_t printer;
+
+  // test::TabFoo f;
+  test::TabBar t;
+
+  db(select(t.alpha).from(t).where(true).group_by(t.alpha));
+
+  return 0;
+}
diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
index 66ba4a0f..87552173 100644
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -30,6 +30,7 @@ target_compile_options(sqlpp11_testing INTERFACE -Wall -Wextra -pedantic)
 endif ()
 
 set(test_names
+  Aggregates
   BooleanExpression
   CustomQuery
   Interpret
diff --git a/tests/SelectType.cpp b/tests/SelectType.cpp
index c15b0c61..1e0dd7a7 100644
--- a/tests/SelectType.cpp
+++ b/tests/SelectType.cpp
@@ -375,7 +375,7 @@ int SelectType(int, char**)
   static_assert(sqlpp::is_boolean_t<decltype(select(r.a).from(r))>::value, "select(bool) has to be a bool");
   auto s1 = sqlpp::select()
                 .flags(sqlpp::distinct, sqlpp::straight_join)
-                .columns(l.alpha, l.beta, select(r.a).from(r))
+                .columns(l.gamma, r.a)
                 .from(r, t, l)
                 .where(t.beta == "hello world" and select(t.gamma).from(t))  // .as(alias::right))
                 .group_by(l.gamma, r.a)