Add sqlpp::compat::make_unique (#527)

* Add sqlpp::compat::make_unique which calls std::make_unique in C++14 or newer and falls back to a custom implementation in C++11 mode.

* Add tests for sqlpp::compat::make_unique

include/sqlpp11/compat/make_unique.h

@@ -0,0 +1,51 @@
+#pragma once
+
+/*
+ * Copyright (c) 2023, Vesselin Atanasov
+ * 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 <memory>
+
+#ifdef _MSVC_LANG
+#define CXX_STD_VER _MSVC_LANG
+#else
+#define CXX_STD_VER __cplusplus
+#endif
+
+namespace sqlpp
+{
+  namespace compat
+  {
+    template <typename T, typename... Args>
+    std::unique_ptr<T> make_unique(Args&&... args)
+    {
+#if CXX_STD_VER >= 201402L
+      return std::make_unique<T>(std::forward<Args>(args)...);
+#else
+      return std::unique_ptr<T>(new T(std::forward<Args>(args)...));
+#endif
+    }
+  }  // namespace compat
+}  // namespace sqlpp

include/sqlpp11/connection.h

@@ -27,6 +27,8 @@
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+#include <sqlpp11/compat/make_unique.h>
+
 #include <functional>
 #include <memory>
 
@@ -51,7 +53,7 @@ namespace sqlpp
     {
     }
 
-    normal_connection(const _config_ptr_t& config) : ConnectionBase{std::make_unique<_handle_t>(config)}
+    normal_connection(const _config_ptr_t& config) : ConnectionBase{compat::make_unique<_handle_t>(config)}
     {
     }
 
@@ -65,7 +67,7 @@ namespace sqlpp
     // creates a connection handle and connects to database
     void connectUsing(const _config_ptr_t& config) noexcept(false)
     {
-      ConnectionBase::_handle = std::make_unique<_handle_t>(config);
+      ConnectionBase::_handle = compat::make_unique<_handle_t>(config);
     }
 
   private:
@@ -121,7 +123,7 @@ namespace sqlpp
     }
 
     pooled_connection(const _config_ptr_t& config, _pool_core_ptr_t pool_core)
-        : ConnectionBase{std::make_unique<_handle_t>(config)}, _pool_core{pool_core}
+        : ConnectionBase{compat::make_unique<_handle_t>(config)}, _pool_core{pool_core}
     {
     }
 

include/sqlpp11/postgresql/connection.h

@@ -32,6 +32,7 @@
 #include <iostream>
 #include <sstream>
 
+#include <sqlpp11/compat/make_unique.h>
 #include <sqlpp11/connection.h>
 #include <sqlpp11/detail/float_safe_ostringstream.h>
 #include <sqlpp11/postgresql/bind_result.h>
@@ -71,8 +72,7 @@ namespace sqlpp
           std::cerr << "PostgreSQL debug: preparing: " << stmt << std::endl;
         }
 
-        return std::unique_ptr<detail::prepared_statement_handle_t>(new detail::prepared_statement_handle_t
-                                                                    (*handle, stmt, param_count));
+        return sqlpp::compat::make_unique<detail::prepared_statement_handle_t>(*handle, stmt, param_count);
       }
 
       inline void execute_prepared_statement(std::unique_ptr<connection_handle>& handle, std::shared_ptr<detail::prepared_statement_handle_t>& prepared)

tests/core/CMakeLists.txt

@@ -26,3 +26,4 @@ add_subdirectory(serialize)
 add_subdirectory(constraints)
 add_subdirectory(static_asserts)
 add_subdirectory(types)
+add_subdirectory(compat)

tests/core/compat/CMakeLists.txt

@@ -0,0 +1,38 @@
+# Copyright (c) 2013-2015, Roland Bock
+# Copyright (c) 2023, Vesselin Atanasov
+# 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.
+
+function(test_compile name)
+    set(target sqlpp11_compat_${name})
+    add_executable(${target} ${name}.cpp)
+    target_link_libraries(${target} PRIVATE sqlpp11::sqlpp11 sqlpp11_testing)
+    # conditionally bump to a higher C++ standard to test compatibility
+    if (SQLPP11_TESTS_CXX_STD)
+        set_property(TARGET sqlpp11_compat_${name} PROPERTY CXX_STANDARD ${SQLPP11_TESTS_CXX_STD})
+        set_property(TARGET sqlpp11_compat_${name} PROPERTY CXX_STANDARD_REQUIRED yes)
+        set_property(TARGET sqlpp11_compat_${name} PROPERTY CXX_EXTENSIONS no)
+    endif()
+endfunction()
+
+test_compile(make_unique)

tests/core/compat/make_unique.cpp

@@ -0,0 +1,35 @@
+/*
+ * Copyright (c) 2023, Vesselin Atanasov
+ * 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 <sqlpp11/compat/make_unique.h>
+
+int main(int, char* [])
+{
+  auto var_1 = sqlpp::compat::make_unique<int>();
+  static_assert(std::is_same<decltype(var_1), std::unique_ptr<int>>::value, "make_unique<int> returns wrong type");
+
+  auto var_2 = sqlpp::compat::make_unique<std::pair<int, bool>>(1, true);
+  static_assert(std::is_same<decltype(var_2), std::unique_ptr<std::pair<int, bool>>>::value, "make_unique<std::pair<int, bool>> returns wrong type");
+}

tests/include/ConnectionPoolTests.h

@@ -27,6 +27,8 @@ ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
 
+#include <sqlpp11/compat/make_unique.h>
+
 #include <random>
 #include <set>
 #include <thread>
@@ -238,7 +240,7 @@ namespace sqlpp
       void test_destruction_order(typename Pool::_config_ptr_t config)
       {
         // Create a pool, get a connection from it and then destroy the pool before the connection
-        auto pool = std::make_unique<Pool>(config, 5);
+        auto pool = sqlpp::compat::make_unique<Pool>(config, 5);
         auto conn = pool->get();
         pool = nullptr;
       }