attempt to emulate exemplar modules PR

Author: JeffGarland

CMakeLists.txt

@@ -9,6 +9,8 @@ project(
     VERSION 0.0.1
 )
 
+set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
+
 # [CMAKE.SKIP_TESTS]
 option(
     BEMAN_SCOPE_BUILD_TESTS
@@ -29,10 +31,11 @@ option(
     ${PROJECT_IS_TOP_LEVEL}
 )
 
-add_library(beman.scope INTERFACE)
+add_library(beman.scope)
 add_library(beman::scope ALIAS beman.scope)
 
 # gersemi: off
+
 set_target_properties(
     beman.scope
     PROPERTIES
@@ -42,22 +45,31 @@ set_target_properties(
 
 target_sources(
     beman.scope
-    INTERFACE
+    PUBLIC
         FILE_SET HEADERS
         BASE_DIRS include
         FILES include/beman/scope/scope.hpp
+    PUBLIC
+        FILE_SET CXX_MODULES
+        BASE_DIRS include
+        FILES include/beman/scope/beman.scope.cppm
 )
 
+include(GNUInstallDirs)
+
 install(
     TARGETS beman.scope
-    EXPORT beman.scope-targets
     COMPONENT beman.scope
+    EXPORT beman.scope-targets
+
+    FILE_SET CXX_MODULES
+        DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}
     FILE_SET HEADERS
 )
+
 # gersemi: on
 
 if(BEMAN_SCOPE_INSTALL_CONFIG_FILE_PACKAGE)
-    include(GNUInstallDirs)
     include(CMakePackageConfigHelpers)
 
     write_basic_package_version_file(
@@ -77,6 +89,7 @@ if(BEMAN_SCOPE_INSTALL_CONFIG_FILE_PACKAGE)
         EXPORT beman.scope-targets
         DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/beman.scope
         NAMESPACE beman::
+        CXX_MODULES_DIRECTORY cxx-modules
         COMPONENT beman.scope
     )
 endif()

tests/CMakeLists.txt

@@ -15,6 +15,18 @@ message("Tests to be built: ${ALL_TESTNAMES}")
 
 include(Catch)
 
+add_executable(test.module)
+target_sources(test.module PRIVATE module.test.cpp)
+target_compile_features(test.module PRIVATE cxx_std_20)
+target_compile_options(test.module PRIVATE "-fmodules")
+# target_link_libraries(
+#     test.module
+#     PUBLIC FILE_SET TYPE CXX_MODULES include/beman/scope/beman.scope.cppm
+#     PRIVATE Catch2::Catch2WithMain beman::scope
+# )
+# catch_discover_tests(test.module)
+
+
 foreach(testname ${ALL_TESTNAMES})
     add_executable(test.${testname})
     target_sources(test.${testname} PRIVATE ${testname}.test.cpp)