Fix C++ module installation

.gitignore

@@ -3,7 +3,7 @@ build*
 /.vs
 /checks.json
 /.vscode
-install_dir/
+install*/
 cmake_build*/
 compile_commands.json
 .cache/

CMakeLists.txt

@@ -7,9 +7,9 @@
 option(BOOST_UT_DISABLE_MODULE "Disable ut module" ON)
 
 if(NOT BOOST_UT_DISABLE_MODULE)
-cmake_minimum_required(VERSION 4.0.0)
+  cmake_minimum_required(VERSION 4.0.0)
 else()
-cmake_minimum_required(VERSION 3.21...3.25)
+  cmake_minimum_required(VERSION 3.21...3.25)
 endif()
 project(
   ut
@@ -33,16 +33,9 @@ option(BOOST_UT_BUILD_BENCHMARKS "Build the benchmarks" OFF)
 option(BOOST_UT_BUILD_EXAMPLES "Build the examples" ${PROJECT_IS_TOP_LEVEL})
 option(BOOST_UT_BUILD_TESTS "Build the tests" ${PROJECT_IS_TOP_LEVEL})
 option(BOOST_UT_ENABLE_INSTALL "Enable install targets" ${PROJECT_IS_TOP_LEVEL})
-option(BOOST_UT_USE_WARNINGS_AS_ERORS "Build the tests" ${PROJECT_IS_TOP_LEVEL})
+option(BOOST_UT_USE_WARNINGS_AS_ERRORS "Treat compile warnings as errors" ${PROJECT_IS_TOP_LEVEL})
 
-add_library(ut INTERFACE)
-if(NOT BOOST_UT_DISABLE_MODULE)
-add_library(ut_module)
-endif()
-target_include_directories(ut INTERFACE $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include>)
-target_compile_features(ut INTERFACE cxx_std_20)
-
-if(BOOST_UT_USE_WARNINGS_AS_ERORS)
+if(BOOST_UT_USE_WARNINGS_AS_ERRORS)
   include(cmake/WarningsAsErrors.cmake)
 endif()
 
@@ -66,52 +59,52 @@ if(BOOST_UT_ENABLE_SANITIZERS)
   )
 endif()
 
-if(BOOST_UT_DISABLE_MODULE)
-  target_compile_definitions(ut INTERFACE BOOST_UT_DISABLE_MODULE)
-endif()
-
-if(NOT BOOST_UT_DISABLE_MODULE)
-target_sources(ut_module PUBLIC FILE_SET CXX_MODULES FILES include/boost/ut.cppm)
-endif()
-
+add_library(ut INTERFACE)
 if(NOT TARGET Boost::ut)
   add_library(Boost::ut ALIAS ut)
 endif()
-
-if(NOT BOOST_UT_DISABLE_MODULE)
-add_library(Boost::ut_module ALIAS ut_module)
-endif()
-
-include(GNUInstallDirs)
-include(CMakePackageConfigHelpers)
-
-install(
-  FILES include/boost/ut.hpp include/boost/ut.cppm
-  DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}/boost
-)
-
+target_compile_features(ut INTERFACE cxx_std_20)
+target_sources(ut INTERFACE FILE_SET HEADERS BASE_DIRS include FILES include/boost/ut.hpp)
 install(
   TARGETS ut
   EXPORT ut_Targets
-  INCLUDES DESTINATION include
+  FILE_SET HEADERS
 )
+
+if(BOOST_UT_DISABLE_MODULE)
+  target_compile_definitions(ut INTERFACE BOOST_UT_DISABLE_MODULE)
+else()
+  include(GNUInstallDirs)
+
+  add_library(ut_module)
+  add_library(Boost::ut_module ALIAS ut_module)
+  target_compile_features(ut_module PUBLIC cxx_std_23)
+  set_target_properties(ut_module PROPERTIES CXX_MODULE_STD ON)
+  target_sources(ut_module PUBLIC FILE_SET CXX_MODULES BASE_DIRS include FILES include/boost/ut.cppm)
+  target_link_libraries(ut_module PUBLIC Boost::ut)
+  install(
+    TARGETS ut_module
+    EXPORT ut_Targets
+    FILE_SET CXX_MODULES
+    DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}"
+  )
+endif()
+
 install(
   EXPORT ut_Targets
   FILE utConfig.cmake
   NAMESPACE Boost::
   DESTINATION lib/cmake/ut
+  CXX_MODULES_DIRECTORY "."
 )
 
+include(CMakePackageConfigHelpers)
 write_basic_package_version_file(
   "utConfigVersion.cmake"
   VERSION ${PROJECT_VERSION}
-  COMPATIBILITY SameMajorVersion
-  ARCH_INDEPENDENT
-)
-install(
-  FILES "${PROJECT_BINARY_DIR}/utConfigVersion.cmake"
-  DESTINATION lib/cmake/ut
+  COMPATIBILITY SameMajorVersion ARCH_INDEPENDENT
 )
+install(FILES "${PROJECT_BINARY_DIR}/utConfigVersion.cmake" DESTINATION lib/cmake/ut)
 
 if(EMSCRIPTEN)
   set(CMAKE_EXECUTABLE_SUFFIX ".js")

include/boost/ut.cppm

@@ -6,10 +6,10 @@ module;
 #endif
 
 export module boost.ut;
-export import std;
+import std;
 
 #define BOOST_UT_CXX_MODULES 1
-#include "ut.hpp"
+#include <boost/ut.hpp>
 
 template class boost::ut::reporter_junit<boost::ut::printer>;
 template void boost::ut::reporter_junit<boost::ut::printer>::on<bool>(boost::ut::events::log<bool>);

test/CMakeLists.txt

@@ -28,3 +28,6 @@ endif()
 
 add_subdirectory(ut)
 add_subdirectory(ft)
+if(TARGET Boost::ut_module)
+  add_subdirectory(ut-module)
+endif()

test/ut-module/CMakeLists.txt

@@ -0,0 +1,16 @@
+# not using ut_add_custom_command_or_test() to explicitly link against Boost:ut_module
+add_executable(from-ut-module main.cpp)
+target_compile_features(from-ut-module PRIVATE cxx_std_20)
+target_link_libraries(from-ut-module PRIVATE Boost::ut_module)
+set_target_properties(from-ut-module PROPERTIES CXX_SCAN_FOR_MODULES ON)
+
+if(BOOST_UT_ENABLE_RUN_AFTER_BUILD)
+  add_custom_command(
+    TARGET from-ut-module
+    POST_BUILD
+    COMMAND from-ut-module
+    COMMENT "Running from-ut-module"
+  )
+else()
+  add_test(NAME from-ut-module COMMAND from-ut-module)
+endif()

test/ut-module/main.cpp

@@ -0,0 +1,18 @@
+//
+// Copyright (c) 2019-2020 Kris Jusiak (kris at jusiak dot net)
+//
+// Distributed under the Boost Software License, Version 1.0.
+// (See accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt)
+//
+import boost.ut;
+
+int main() {
+  using namespace boost::ut;
+
+  "module"_test = [] {
+    // clang-format off
+    expect(42_i == 42 and constant<3 == 3_i>);
+    // clang-format on
+  };
+}