When installing also install the module (.cppm) files

CMakeLists.txt

@@ -99,7 +99,7 @@ if(BUILD_POSTGRESQL_CONNECTOR)
 endif()
 
 if(BUILD_WITH_MODULES)
-    add_subdirectory(module)
+    add_subdirectory(modules)
 endif()
 
 ### Packaging
@@ -112,7 +112,6 @@ write_basic_package_version_file(Sqlpp23ConfigVersion.cmake
     ARCH_INDEPENDENT
 )
 
-
 install(FILES ${CMAKE_CURRENT_BINARY_DIR}/Sqlpp23ConfigVersion.cmake
     DESTINATION ${SQLPP23_INSTALL_CMAKEDIR}
 )
@@ -151,7 +150,6 @@ if(BUILD_POSTGRESQL_CONNECTOR)
     install_component(NAME Sqlpp23PostgreSQL TARGETS sqlpp23_postgresql DIRECTORY postgresql)
 endif()
 
-
 ### Tests
 if(CMAKE_PROJECT_NAME STREQUAL PROJECT_NAME AND BUILD_TESTING)
     add_subdirectory(tests)

module/CMakeLists.txt → modules/CMakeLists.txt

@@ -22,6 +22,19 @@
 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 # SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
+# The module targets should really be of INTERFACE type, because it is a header-only
+# library which doesn't build any library files for them. However CMake disallows
+# using the INTERFACE library type if the library has any C++20 modules. For details
+# see https://discourse.cmake.org/t/header-only-libraries-and-c-20-modules/10680
+#
+# On the other hand using a regular library type for the module libraries means
+# that any call to install(TARGET...) for the module targets will fail because it will
+# also try to install the non-existent library file. This in turn means that we cannot
+# use install(TARGET...) to install the .cmm files and have to resort to
+# install(FILES...)
+
+set(SQLPP23_INSTALL_MODULE_DIR ${CMAKE_INSTALL_PREFIX}/modules/sqlpp23)
+
 # Core library module
 add_library(sqlpp23.core.module)
 target_sources(sqlpp23.core.module
@@ -30,6 +43,7 @@ target_sources(sqlpp23.core.module
     sqlpp23.core.cppm
 )
 target_link_libraries(sqlpp23.core.module PUBLIC sqlpp23)
+install(FILES sqlpp23.core.cppm DESTINATION ${SQLPP23_INSTALL_MODULE_DIR})
 
 add_library(sqlpp23.mock_db.module)
 target_sources(sqlpp23.mock_db.module
@@ -38,6 +52,7 @@ target_sources(sqlpp23.mock_db.module
     sqlpp23.mock_db.cppm
 )
 target_link_libraries(sqlpp23.mock_db.module PUBLIC sqlpp23.core.module)
+install(FILES sqlpp23.mock_db.cppm DESTINATION ${SQLPP23_INSTALL_MODULE_DIR})
 
 if(BUILD_SQLITE3_CONNECTOR OR BUILD_SQLCIPHER_CONNECTOR)
     add_library(sqlpp23.sqlite3.module)
@@ -47,6 +62,7 @@ if(BUILD_SQLITE3_CONNECTOR OR BUILD_SQLCIPHER_CONNECTOR)
         sqlpp23.sqlite3.cppm
     )
     target_link_libraries(sqlpp23.sqlite3.module PUBLIC sqlpp23.core.module sqlpp23::sqlite3)
+    install(FILES sqlpp23.sqlite3.cppm DESTINATION ${SQLPP23_INSTALL_MODULE_DIR})
 endif()
 
 if(BUILD_MYSQL_CONNECTOR OR BUILD_MARIADB_CONNECTOR)
@@ -57,6 +73,7 @@ if(BUILD_MYSQL_CONNECTOR OR BUILD_MARIADB_CONNECTOR)
         sqlpp23.mysql.cppm
     )
     target_link_libraries(sqlpp23.mysql.module PUBLIC sqlpp23.core.module sqlpp23::mysql)
+    install(FILES sqlpp23.mysql.cppm DESTINATION ${SQLPP23_INSTALL_MODULE_DIR})
 endif()
 
 if(BUILD_POSTGRESQL_CONNECTOR)
@@ -67,6 +84,5 @@ if(BUILD_POSTGRESQL_CONNECTOR)
         sqlpp23.postgresql.cppm
     )
     target_link_libraries(sqlpp23.postgresql.module PUBLIC sqlpp23.core.module sqlpp23::postgresql)
+    install(FILES sqlpp23.postgresql.cppm DESTINATION ${SQLPP23_INSTALL_MODULE_DIR})
 endif()
-
-

tests/core/CMakeLists.txt

@@ -27,7 +27,7 @@ if(BUILD_WITH_MODULES)
     target_sources(sqlpp23.test.core.tables.module
       PUBLIC
         FILE_SET all_my_modules TYPE CXX_MODULES FILES
-        module/sqlpp23.test.core.tables.cppm
+        modules/sqlpp23.test.core.tables.cppm
     )
     target_link_libraries(sqlpp23.test.core.tables.module PUBLIC sqlpp23.core.module)
 endif()

tests/core/module/sqlpp23.test.core.tables.cppm → tests/core/modules/sqlpp23.test.core.tables.cppm

@@ -1,7 +1,7 @@
 module;
 
 // clang-format off
-// generated by ./scripts/sqlpp23-ddl2cpp --path-to-ddl tests/include/sqlpp23/tests/core/tables.sql --path-to-module tests/core/module/sqlpp23.test.core.tables.cppm --module-name=sqlpp23.test.core.tables --namespace test --assume-auto-id
+// generated by ./scripts/sqlpp23-ddl2cpp --path-to-ddl tests/include/sqlpp23/tests/core/tables.sql --path-to-module tests/core/modules/sqlpp23.test.core.tables.cppm --module-name=sqlpp23.test.core.tables --namespace test --assume-auto-id
 
 #include <optional>
 

tests/mysql/CMakeLists.txt

@@ -27,7 +27,7 @@ if(BUILD_WITH_MODULES)
     target_sources(sqlpp23.test.mysql.tables.module
       PUBLIC
         FILE_SET all_my_modules TYPE CXX_MODULES FILES
-        module/sqlpp23.test.mysql.tables.cppm
+        modules/sqlpp23.test.mysql.tables.cppm
     )
     target_link_libraries(sqlpp23.test.mysql.tables.module PUBLIC sqlpp23.core.module)
 endif()

tests/mysql/module/sqlpp23.test.mysql.tables.cppm → tests/mysql/modules/sqlpp23.test.mysql.tables.cppm

@@ -1,7 +1,7 @@
 module;
 
 // clang-format off
-// generated by ./scripts/sqlpp23-ddl2cpp --path-to-ddl tests/include/sqlpp23/tests/mysql/tables.sql --path-to-module tests/mysql/module/sqlpp23.test.mysql.tables.cppm --namespace test --assume-auto-id --module-name sqlpp23.test.mysql.tables --generate-table-creation-helper
+// generated by ./scripts/sqlpp23-ddl2cpp --path-to-ddl tests/include/sqlpp23/tests/mysql/tables.sql --path-to-module tests/mysql/modules/sqlpp23.test.mysql.tables.cppm --namespace test --assume-auto-id --module-name sqlpp23.test.mysql.tables --generate-table-creation-helper
 
 #include <optional>
 

tests/postgresql/CMakeLists.txt

@@ -27,7 +27,7 @@ if(BUILD_WITH_MODULES)
   target_sources(sqlpp23.test.postgresql.tables.module
     PUBLIC
       FILE_SET all_my_modules TYPE CXX_MODULES FILES
-      module/sqlpp23.test.postgresql.tables.cppm
+      modules/sqlpp23.test.postgresql.tables.cppm
   )
   target_link_libraries(sqlpp23.test.postgresql.tables.module PUBLIC sqlpp23.core.module)
 endif()

tests/postgresql/module/sqlpp23.test.postgresql.tables.cppm → tests/postgresql/modules/sqlpp23.test.postgresql.tables.cppm

@@ -1,7 +1,7 @@
 module;
 
 // clang-format off
-// generated by ./scripts/sqlpp23-ddl2cpp --path-to-ddl tests/include/sqlpp23/tests/postgresql/tables.sql --path-to-module tests/postgresql/module/sqlpp23.test.postgresql.tables.cppm --namespace test --assume-auto-id --module-name sqlpp23.test.postgresql.tables --generate-table-creation-helper
+// generated by ./scripts/sqlpp23-ddl2cpp --path-to-ddl tests/include/sqlpp23/tests/postgresql/tables.sql --path-to-module tests/postgresql/modules/sqlpp23.test.postgresql.tables.cppm --namespace test --assume-auto-id --module-name sqlpp23.test.postgresql.tables --generate-table-creation-helper
 
 #include <optional>
 

tests/sqlite3/CMakeLists.txt

@@ -27,7 +27,7 @@ if(BUILD_WITH_MODULES)
     target_sources(sqlpp23.test.sqlite3.tables.module
       PUBLIC
         FILE_SET all_my_modules TYPE CXX_MODULES FILES
-        module/sqlpp23.test.sqlite3.tables.cppm
+        modules/sqlpp23.test.sqlite3.tables.cppm
     )
     target_link_libraries(sqlpp23.test.sqlite3.tables.module PUBLIC sqlpp23.core.module)
 endif()

tests/sqlite3/module/sqlpp23.test.sqlite3.tables.cppm → tests/sqlite3/modules/sqlpp23.test.sqlite3.tables.cppm

@@ -1,7 +1,7 @@
 module;
 
 // clang-format off
-// generated by ./scripts/sqlpp23-ddl2cpp --path-to-ddl tests/include/sqlpp23/tests/sqlite3/tables.sql --path-to-module tests/sqlite3/module/sqlpp23.test.sqlite3.tables.cppm --namespace test --assume-auto-id --module-name sqlpp23.test.sqlite3.tables --generate-table-creation-helper
+// generated by ./scripts/sqlpp23-ddl2cpp --path-to-ddl tests/include/sqlpp23/tests/sqlite3/tables.sql --path-to-module tests/sqlite3/modules/sqlpp23.test.sqlite3.tables.cppm --namespace test --assume-auto-id --module-name sqlpp23.test.sqlite3.tables --generate-table-creation-helper
 
 #include <optional>