Modules support

.github/workflows/modules.yml

@@ -0,0 +1,55 @@
+name: Build & Test with modules
+
+on: 
+    push:   
+        branches:
+        - main
+    pull_request:
+        branches:
+        - main
+    workflow_dispatch:
+    release:
+        types: [published]
+
+jobs:
+  build:
+    name: ${{ matrix.runs_on }}-${{ matrix.compiler }}-${{ matrix.configure_preset }}
+    runs-on: ${{ matrix.runs_on }}
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - runs_on: windows-2025-vs2026
+            compiler: msvc-14.50
+            configure_preset: "x64-vs"
+            build_preset: "x64-vs-build"
+            test_preset : "x64-vs-test"
+          # To be uncommented  once GitHub Actions add GCC 15 or 16 with Ubuntu 26
+          # - runs_on: ubuntu-latest
+          #  compiler: gcc-15
+          # configure_preset: "linux-debug"
+          # build_preset: "linux-debug-build"
+          # test_preset : "linux-debug-test"
+          # - runs_on: ubuntu-latest
+          # compiler: clang-18
+          # cc: clang
+          # cxx: clang++
+          # configure_preset: "linux-debug"
+          # build_preset: "linux-debug-build"
+          # test_preset : "linux-debug-test"
+    steps:
+
+    - uses: actions/checkout@v6
+
+    - uses: lukka/get-cmake@latest
+
+    - name: "Build & Test"
+      uses: lukka/run-cmake@v10
+      env:
+          CC: ${{ matrix.cc }}
+          CXX: ${{ matrix.cxx }}
+      with:
+        configurePreset: ${{ matrix.configure_preset }}
+        configurePresetAdditionalArgs: "['-DUT_ENABLE_MODULES=ON']"
+        buildPreset: ${{ matrix.build_preset }}
+        testPreset: ${{ matrix.test_preset }}

.gitignore

@@ -1,6 +1,8 @@
 build*
+out/
 compile_commands.json
 
 .vscode
 .cache
 .DS_Store
+.vs

CMakeLists.txt

@@ -1,40 +1,76 @@
-cmake_minimum_required(VERSION 3.24)
+cmake_minimum_required(VERSION 3.31) # Raise to 4.3 on availability global release and availability in CI/CD
+
+set(CMAKE_EXPERIMENTAL_CXX_IMPORT_STD "d0edc3af-4c50-42ea-a356-e2862fe7a444") # Should be removed after 4.3 is released
 
 include(cmake/prelude.cmake)
 
 project(
-    ut
-    VERSION 1.1.0
-    LANGUAGES CXX
+  ut
+  VERSION 1.2.0
+  LANGUAGES CXX
 )
 
 include(cmake/project-is-top-level.cmake)
 include(cmake/variables.cmake)
 
-add_library(${PROJECT_NAME}_${PROJECT_NAME} INTERFACE)
+option(UT_ENABLE_MODULES "Enable modules with import std" OFF)
+option(UT_COMPILE_TIME "Enable compile time features" OFF)
+
+if(UT_ENABLE_MODULES)
+  if(NOT CMAKE_GENERATOR MATCHES "Visual Studio") ## Support should be added with 4.4, todo: check when available
+    set(CMAKE_CXX_MODULE_STD 1)
+  endif()
+endif()
+
+if(UT_ENABLE_MODULES)
+  add_library(${PROJECT_NAME}_${PROJECT_NAME} STATIC)
+  set(UT_LIB_TYPE PUBLIC)
+else()
+  add_library(${PROJECT_NAME}_${PROJECT_NAME} INTERFACE)
+  set(UT_LIB_TYPE INTERFACE)
+endif()
 add_library(${PROJECT_NAME}::${PROJECT_NAME} ALIAS ${PROJECT_NAME}_${PROJECT_NAME})
 
-if (MSVC)
-   string(REGEX MATCH "\/cl(.exe)?$" matched_cl ${CMAKE_CXX_COMPILER})
-   if (matched_cl)
-      # for a C++ standards compliant preprocessor, not needed for clang-cl
-      target_compile_options(${PROJECT_NAME}_${PROJECT_NAME} INTERFACE "/Zc:preprocessor" /GL /permissive- /Zc:lambda)
-      target_link_options(${PROJECT_NAME}_${PROJECT_NAME} INTERFACE /LTCG /INCREMENTAL:NO)
-   endif()
+if(PROJECT_IS_TOP_LEVEL)
+  include(cmake/dev-mode.cmake)
+endif()
+
+target_compile_features(${PROJECT_NAME}_${PROJECT_NAME} ${UT_LIB_TYPE} cxx_std_23)
+
+if(UT_ENABLE_MODULES)
+  target_sources(${PROJECT_NAME}_${PROJECT_NAME}
+    PUBLIC
+      FILE_SET modules TYPE CXX_MODULES
+      BASE_DIRS "${PROJECT_SOURCE_DIR}/modules"
+      FILES
+        "${PROJECT_SOURCE_DIR}/modules/ut.ixx"
+  )
+
+  target_compile_definitions(${PROJECT_NAME}_${PROJECT_NAME} PRIVATE UT_ENABLE_MODULES)
+endif()
+
+if(UT_COMPILE_TIME)
+  target_compile_definitions(${PROJECT_NAME}_${PROJECT_NAME} ${UT_LIB_TYPE} UT_COMPILE_TIME)
+endif()
+
+if(MSVC)
+  string(REGEX MATCH "\/cl(.exe)?$" matched_cl ${CMAKE_CXX_COMPILER})
+  if(matched_cl)
+    # for a C++ standards compliant preprocessor, not needed for clang-cl
+    target_compile_options(${PROJECT_NAME}_${PROJECT_NAME} INTERFACE "/Zc:preprocessor" /GL /permissive- /Zc:lambda)
+    target_link_options(${PROJECT_NAME}_${PROJECT_NAME} INTERFACE /LTCG /INCREMENTAL:NO)
+  endif()
 endif()
 
 set_property(TARGET ${PROJECT_NAME}_${PROJECT_NAME} PROPERTY EXPORT_NAME ${PROJECT_NAME})
 
-target_compile_features(${PROJECT_NAME}_${PROJECT_NAME} INTERFACE cxx_std_23)
 target_include_directories(
-   ${PROJECT_NAME}_${PROJECT_NAME} ${warning_guard}
-    INTERFACE "$<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include>"
+  ${PROJECT_NAME}_${PROJECT_NAME} ${warning_guard}
+  INTERFACE
+    "$<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include>"
+    "$<INSTALL_INTERFACE:include>"
 )
 
 if(NOT CMAKE_SKIP_INSTALL_RULES)
   include(cmake/install-rules.cmake)
 endif()
-
-if (PROJECT_IS_TOP_LEVEL)
-  include(cmake/dev-mode.cmake)
-endif()

CMakePresets.json

@@ -0,0 +1,132 @@
+{
+  "version": 9,
+  "cmakeMinimumRequired": {
+    "major": 3,
+    "minor": 31,
+    "patch": 0
+  },
+  "configurePresets": [
+    {
+      "name": "windows-base",
+      "hidden": true,
+      "generator": "Ninja",
+      "binaryDir": "${sourceDir}/out/build/${presetName}",
+      "installDir": "${sourceDir}/out/install/${presetName}",
+      "condition": {
+        "type": "equals",
+        "lhs": "${hostSystemName}",
+        "rhs": "Windows"
+      }
+    },
+    {
+      "name": "x64",
+      "displayName": "x64",
+      "description": "Target Windows (64-bit) with the Visual Studio development environment.",
+      "inherits": "windows-base",
+      "architecture": {
+        "value": "x64",
+        "strategy": "external"
+      }
+    },
+    {
+      "name": "windows-base-preview",
+      "description": "Base preset for MSVC v14.51",
+      "hidden": true,
+      "generator": "Ninja",
+      "binaryDir": "${sourceDir}/out/build/${presetName}",
+      "installDir": "${sourceDir}/out/install/${presetName}",
+      "condition": {
+        "type": "equals",
+        "lhs": "${hostSystemName}",
+        "rhs": "Windows"
+      },
+      "toolset": {
+        "value": "v145,host=x64,version=14.51"
+      }
+    },
+    {
+      "name": "x64-preview",
+      "displayName": "x64 Debug (MSVC v14.51 Preview)",
+      "inherits": "windows-base-preview",
+      "architecture": {
+        "value": "x64",
+        "strategy": "external"
+      }
+    },
+    {
+      "name": "windows-vs-base",
+      "hidden": true,
+      "generator": "Visual Studio 18 2026",
+      "binaryDir": "${sourceDir}/out/build/${presetName}",
+      "installDir": "${sourceDir}/out/install/${presetName}",
+      "condition": {
+        "type": "equals",
+        "lhs": "${hostSystemName}",
+        "rhs": "Windows"
+      }
+    },
+    {
+      "name": "x64-vs",
+      "displayName": "x64 (VS generator)",
+      "inherits": "windows-vs-base",
+      "architecture": "x64"
+    },
+    {
+      "name": "linux-debug",
+      "displayName": "Linux Debug",
+      "generator": "Ninja",
+      "binaryDir": "${sourceDir}/out/build/${presetName}",
+      "installDir": "${sourceDir}/out/install/${presetName}",
+      "cacheVariables": {
+        "CMAKE_BUILD_TYPE": "Debug"
+      },
+      "condition": {
+        "type": "equals",
+        "lhs": "${hostSystemName}",
+        "rhs": "Linux"
+      }
+    }
+  ],
+  "buildPresets": [
+    {
+      "name": "x64-build",
+      "configurePreset": "x64"
+    },
+    {
+      "name": "x64-vs-build",
+      "configurePreset": "x64-vs",
+      "configuration": "Debug"
+    },
+    {
+      "name": "x64-preview-build",
+      "configurePreset": "x64-preview"
+    },
+    {
+      "name": "linux-debug-build",
+      "configurePreset": "linux-debug"
+    }
+  ],
+  "testPresets": [
+    {
+      "name": "x64-test",
+      "configurePreset": "x64"
+    },
+
+    {
+      "name": "x64-vs-test",
+      "configurePreset": "x64-vs",
+      "configuration": "Debug",
+      "output": {
+        "outputOnFailure": true
+      }
+    },
+    {
+      "name": "x64-preview-test",
+      "configurePreset": "x64-preview"
+    },
+    {
+      "name": "linux-debug-test",
+      "configurePreset": "linux-debug"
+    }
+  ]
+}

README.md

@@ -12,12 +12,28 @@ A simple and fast compiling unit test library.
 
 ### Features
 
-- Single header
+#### Single header
 
-To enable compile time testing you must define the macro: `UT_COMPILE_TIME`
+To enable compile time testing, set the option `UT_COMPILE_TIME` to ON. For example:
+```cmake
+set(UT_COMPILE_TIME ON)
+```
 
 Runtime testing is always enabled.
 
+#### Modules support
+
+The library supports C++ 20/23 modules. To enable, set the option `UT_ENABLE_MODULES` to ON. For example:
+```cmake
+set (UT_ENABLE_MODULES ON)
+```
+You can then import the library:
+```cpp
+import ut;
+```
+
+Please note that modules integration requires compiler and build tools that support `import std`.
+
 ### Running Specific Tests
 
 Use the `UT_RUN` environment variable to run specific tests by name:
@@ -33,6 +49,7 @@ UT_RUN="[test1,test2,test3]" ./my_tests
 ### Requirements
 
 - C++23
+- CMake 3.31
 
 ## Example
 

cmake/dev-mode.cmake

@@ -78,3 +78,9 @@ set_tests_properties(ut_run_no_match PROPERTIES
    ENVIRONMENT "UT_RUN=nonexistent"
    PASS_REGULAR_EXPRESSION "tests: 0 \\(0 passed"
 )
+
+if (UT_ENABLE_MODULES)
+  add_executable(ut_module_consumer_tests "${PROJECT_SOURCE_DIR}/tests/ut_module_consumer_tests.cpp")
+  target_link_libraries(ut_module_consumer_tests PRIVATE ${PROJECT_NAME}::${PROJECT_NAME})
+  add_test(NAME ut_module_consumer_import COMMAND ut_module_consumer_tests)
+endif()

cmake/install-config.cmake

@@ -1 +1 @@
-include("${CMAKE_CURRENT_LIST_DIR}/${PROJECT_NAME}Targets.cmake")
+include("${CMAKE_CURRENT_LIST_DIR}/utTargets.cmake")

cmake/install-rules.cmake

@@ -1,7 +1,3 @@
-if(PROJECT_IS_TOP_LEVEL)
-  set(CMAKE_INSTALL_INCLUDEDIR include/${PROJECT_NAME} CACHE PATH "")
-endif()
-
 # Project is configured with no languages, so tell GNUInstallDirs the lib dir
 set(CMAKE_INSTALL_LIBDIR lib CACHE PATH "")
 
@@ -17,11 +13,21 @@ install(
     COMPONENT ${PROJECT_NAME}_Development
 )
 
-install(
-    TARGETS ${PROJECT_NAME}_${PROJECT_NAME}
-    EXPORT ${PROJECT_NAME}Targets
-    INCLUDES DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}"
-)
+if(UT_ENABLE_MODULES)
+  install(
+      TARGETS ${PROJECT_NAME}_${PROJECT_NAME}
+      EXPORT ${PROJECT_NAME}Targets
+      FILE_SET modules DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}"
+      CXX_MODULES_BMI DESTINATION "" # BMIs are not portable; suppress installation
+      COMPONENT ${PROJECT_NAME}_Development
+  )
+else()
+  install(
+      TARGETS ${PROJECT_NAME}_${PROJECT_NAME}
+      EXPORT ${PROJECT_NAME}Targets
+      COMPONENT ${PROJECT_NAME}_Development
+  )
+endif()
 
 write_basic_package_version_file(
     "${package}ConfigVersion.cmake"
@@ -53,6 +59,7 @@ install(
     EXPORT ${PROJECT_NAME}Targets
     NAMESPACE ${PROJECT_NAME}::
     DESTINATION "${zb8_INSTALL_CMAKEDIR}"
+    CXX_MODULES_DIRECTORY modules
     COMPONENT ${PROJECT_NAME}_Development
 )