Merge branch 'backport-3.28-cxxmodules-no-export-basedirs-as-include-paths'

Source/cmExportFileGenerator.cxx

@@ -11,6 +11,7 @@
 
 #include <cm/memory>
 #include <cm/optional>
+#include <cm/string_view>
 #include <cmext/string_view>
 
 #include "cmsys/FStream.hxx"
@@ -1577,7 +1578,9 @@ void cmExportFileGenerator::GenerateTargetFileSets(cmGeneratorTarget* gte,
         return;
       }
 
-      os << "\n      " << this->GetFileSetDirectories(gte, fileSet, te);
+      if (fileSet->GetType() == "HEADERS"_s) {
+        os << "\n      " << this->GetFileSetDirectories(gte, fileSet, te);
+      }
     }
     os << "\n  )\nendif()\n\n";
   }

Tests/RunCMake/CXXModules/RunCMakeTest.cmake

@@ -260,6 +260,7 @@ if ("export_bmi" IN_LIST CMake_TEST_MODULE_COMPILATION)
   run_cxx_module_test(export-interface-no-properties-build)
   run_cxx_module_test(export-interface-build)
   run_cxx_module_test(export-include-directories-build)
+  run_cxx_module_test(export-include-directories-old-cmake-build)
   run_cxx_module_test(export-usage-build)
   run_cxx_module_test(export-bmi-and-interface-build)
   run_cxx_module_test(export-transitive-targets-build)
@@ -300,6 +301,7 @@ if ("install_bmi" IN_LIST CMake_TEST_MODULE_COMPILATION)
     run_cxx_module_test(export-interface-no-properties-install)
     run_cxx_module_test(export-interface-install)
     run_cxx_module_test(export-include-directories-install)
+    run_cxx_module_test(export-include-directories-old-cmake-install)
     run_cxx_module_test(export-usage-install)
     run_cxx_module_test(export-bmi-and-interface-install)
     run_cxx_module_test(export-transitive-targets-install)

Tests/RunCMake/CXXModules/examples/export-include-directories-old-cmake-build/CMakeLists.txt

@@ -0,0 +1,48 @@
+cmake_minimum_required(VERSION 3.24...3.28)
+project(cxx_modules_export_include_directories_old_cmake CXX)
+
+include("${CMAKE_SOURCE_DIR}/../cxx-modules-rules.cmake")
+
+add_library(export_include_directories_old_cmake)
+target_sources(export_include_directories_old_cmake
+  PUBLIC
+    FILE_SET modules TYPE CXX_MODULES
+      BASE_DIRS
+        "${CMAKE_CURRENT_SOURCE_DIR}"
+      FILES
+        importable.cxx
+  )
+target_compile_features(export_include_directories_old_cmake PUBLIC cxx_std_20)
+
+install(TARGETS export_include_directories_old_cmake
+  EXPORT CXXModules
+  FILE_SET modules DESTINATION "lib/cxx/miu")
+export(EXPORT CXXModules
+  NAMESPACE CXXModules::
+  FILE "${CMAKE_CURRENT_BINARY_DIR}/export_include_directories_old_cmake-targets.cmake"
+  CXX_MODULES_DIRECTORY "export_include_directories_old_cmake-cxx-modules")
+file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/export_include_directories_old_cmake-config.cmake"
+  "include(\"\${CMAKE_CURRENT_LIST_DIR}/export_include_directories_old_cmake-targets.cmake\")
+set(\${CMAKE_FIND_PACKAGE_NAME}_FOUND 1)
+")
+
+set(generator
+  -G "${CMAKE_GENERATOR}")
+if (CMAKE_GENERATOR_TOOLSET)
+  list(APPEND generator
+    -T "${CMAKE_GENERATOR_TOOLSET}")
+endif ()
+if (CMAKE_GENERATOR_PLATFORM)
+  list(APPEND generator
+    -A "${CMAKE_GENERATOR_PLATFORM}")
+endif ()
+
+add_test(NAME export_include_directories_old_cmake_build
+  COMMAND
+    "${CMAKE_COMMAND}"
+    "-Dexpected_source_dir=${CMAKE_CURRENT_SOURCE_DIR}"
+    "-Dexpected_binary_dir=${CMAKE_CURRENT_BINARY_DIR}"
+    "-Dexport_include_directories_old_cmake_DIR=${CMAKE_CURRENT_BINARY_DIR}"
+    ${generator}
+    -S "${CMAKE_CURRENT_SOURCE_DIR}/test"
+    -B "${CMAKE_CURRENT_BINARY_DIR}/test")

Tests/RunCMake/CXXModules/examples/export-include-directories-old-cmake-build/importable.cxx

@@ -0,0 +1,6 @@
+export module importable;
+
+export int from_import()
+{
+  return 0;
+}

Tests/RunCMake/CXXModules/examples/export-include-directories-old-cmake-build/test/CMakeLists.txt

@@ -0,0 +1,17 @@
+cmake_minimum_required(VERSION 3.22)
+project(cxx_modules_library NONE)
+
+set(CMAKE_VERSION "3.22.0") # Trigger non-fileset export code.
+find_package(export_include_directories_old_cmake REQUIRED)
+
+if (NOT TARGET CXXModules::export_include_directories_old_cmake)
+  message(FATAL_ERROR
+    "Missing imported target")
+endif ()
+
+get_property(include_directories TARGET CXXModules::export_include_directories_old_cmake
+  PROPERTY INTERFACE_INCLUDE_DIRECTORIES)
+if (include_directories)
+  message(FATAL_ERROR
+    "Exported include directory on C++ module interface CXXModules::export_include_directories_old_cmake:\n  ${include_directories}")
+endif ()

Tests/RunCMake/CXXModules/examples/export-include-directories-old-cmake-install/CMakeLists.txt

@@ -0,0 +1,51 @@
+cmake_minimum_required(VERSION 3.24...3.28)
+project(cxx_modules_export_include_directories_old_cmake CXX)
+
+include("${CMAKE_SOURCE_DIR}/../cxx-modules-rules.cmake")
+
+add_library(export_include_directories_old_cmake)
+target_sources(export_include_directories_old_cmake
+  PUBLIC
+    FILE_SET modules TYPE CXX_MODULES
+      BASE_DIRS
+        "${CMAKE_CURRENT_SOURCE_DIR}"
+      FILES
+        importable.cxx
+  )
+target_compile_features(export_include_directories_old_cmake PUBLIC cxx_std_20)
+
+install(TARGETS export_include_directories_old_cmake
+  EXPORT CXXModules
+  FILE_SET modules DESTINATION "lib/cxx/miu")
+install(EXPORT CXXModules
+  NAMESPACE CXXModules::
+  DESTINATION "lib/cmake/export_include_directories_old_cmake"
+  FILE "export_include_directories_old_cmake-targets.cmake"
+  CXX_MODULES_DIRECTORY "export_include_directories_old_cmake-cxx-modules")
+file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/export_include_directories_old_cmake-config.cmake"
+  "include(\"\${CMAKE_CURRENT_LIST_DIR}/export_include_directories_old_cmake-targets.cmake\")
+set(\${CMAKE_FIND_PACKAGE_NAME}_FOUND 1)
+")
+install(FILES "${CMAKE_CURRENT_BINARY_DIR}/export_include_directories_old_cmake-config.cmake"
+  DESTINATION "lib/cmake/export_include_directories_old_cmake")
+
+set(generator
+  -G "${CMAKE_GENERATOR}")
+if (CMAKE_GENERATOR_TOOLSET)
+  list(APPEND generator
+    -T "${CMAKE_GENERATOR_TOOLSET}")
+endif ()
+if (CMAKE_GENERATOR_PLATFORM)
+  list(APPEND generator
+    -A "${CMAKE_GENERATOR_PLATFORM}")
+endif ()
+
+add_test(NAME export_include_directories_old_cmake_build
+  COMMAND
+    "${CMAKE_COMMAND}"
+    "-Dexpected_source_dir=${CMAKE_INSTALL_PREFIX}/lib/cxx/miu"
+    "-Dexpected_binary_dir=${CMAKE_INSTALL_PREFIX}/lib/cxx/bmi"
+    "-Dexport_include_directories_old_cmake_DIR=${CMAKE_INSTALL_PREFIX}/lib/cmake/export_include_directories_old_cmake"
+    ${generator}
+    -S "${CMAKE_CURRENT_SOURCE_DIR}/test"
+    -B "${CMAKE_CURRENT_BINARY_DIR}/test")

Tests/RunCMake/CXXModules/examples/export-include-directories-old-cmake-install/importable.cxx

@@ -0,0 +1,6 @@
+export module importable;
+
+export int from_import()
+{
+  return 0;
+}

Tests/RunCMake/CXXModules/examples/export-include-directories-old-cmake-install/test/CMakeLists.txt

@@ -0,0 +1,17 @@
+cmake_minimum_required(VERSION 3.24...3.28)
+project(cxx_modules_library NONE)
+
+set(CMAKE_VERSION "3.22.0") # Trigger non-fileset export code.
+find_package(export_include_directories_old_cmake REQUIRED)
+
+if (NOT TARGET CXXModules::export_include_directories_old_cmake)
+  message(FATAL_ERROR
+    "Missing imported target")
+endif ()
+
+get_property(include_directories TARGET CXXModules::export_include_directories_old_cmake
+  PROPERTY INTERFACE_INCLUDE_DIRECTORIES)
+if (include_directories)
+  message(FATAL_ERROR
+    "Exported include directory on C++ module interface CXXModules::export_include_directories_old_cmake:\n  ${include_directories}")
+endif ()