CMake: Dynamically include and install Helpers and other files

Instead of duplicating file names that need to be include()'ed
in two different places if the files are meant to be used
in both Qt builds and public user projects and then also mention the
name when installing, extract the file names into lists returned by
functions.

Call these functions where needed to iteratively include() the files
as well as install them, without having to remember updating multiple
code locations.

The new functions return the following list of file names:
- upstream cmake modules that need to be included during a Qt build
- public (Qt build and user project) cmake helpers that need to be
  included and installed
- private (Qt build only) cmake helpers that need to be included and
  installed
- public files that need to be installed, but not included
- private files that need to be installed, but not included

We also generate the list of public files to include in
Qt6Config.cmake.

Task-number: QTBUG-86035
Change-Id: I1e7287f4e1d041c723f144ba9626b34f873c4891
Reviewed-by: Alexey Edelev <alexey.edelev@qt.io>
(cherry picked from commit 8c14b0c02f3e4b06a9aa4ea7608360149be4a50f)
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>

4 files changed, 210 insertions, 190 deletions

diff --git a/cmake/QtBaseGlobalTargets.cmake b/cmake/QtBaseGlobalTargets.cmake
index b32692805d..0086f9b5b8 100644
--- a/cmake/QtBaseGlobalTargets.cmake
+++ b/cmake/QtBaseGlobalTargets.cmake
@@ -169,6 +169,11 @@ qt_internal_get_computed_min_cmake_version_for_using_qt(computed_min_version_for
 qt_internal_get_min_new_policy_cmake_version(min_new_policy_version)
 qt_internal_get_max_new_policy_cmake_version(max_new_policy_version)
 
+# Get the list of public helper files that should be automatically included in Qt6Config.cmake.
+# Used in QtConfig.cmake.in template and further down for installation purposes.
+qt_internal_get_qt_build_public_helpers(__qt_cmake_public_helpers)
+list(JOIN __qt_cmake_public_helpers "\n    " QT_PUBLIC_FILES_TO_INCLUDE)
+
 # Generate and install Qt6 config file. Make sure it happens after the global feature evaluation so
 # they can be accessed in the Config file if needed.
 configure_package_config_file(
@@ -202,99 +207,22 @@ qt_install(FILES
     COMPONENT Devel
 )
 
+qt_internal_get_qt_build_private_helpers(__qt_cmake_private_helpers)
+list(TRANSFORM __qt_cmake_private_helpers PREPEND "cmake/")
+list(TRANSFORM __qt_cmake_private_helpers APPEND ".cmake")
+
+qt_internal_get_qt_build_private_files_to_install(__qt_private_files_to_install)
+list(TRANSFORM __qt_private_files_to_install PREPEND "cmake/")
+
 # Install internal CMake files.
 # The functions defined inside can not be used in public projects.
 # They can only be used while building Qt itself.
+set(__private_files
+    ${__qt_cmake_private_helpers}
+    ${__qt_private_files_to_install}
+)
 qt_copy_or_install(FILES
-                   cmake/ModuleDescription.json.in
-                   cmake/PkgConfigLibrary.pc.in
-                   cmake/Qt3rdPartyLibraryConfig.cmake.in
-                   cmake/Qt3rdPartyLibraryHelpers.cmake
-                   cmake/QtAndroidHelpers.cmake
-                   cmake/QtAppHelpers.cmake
-                   cmake/QtAutogenHelpers.cmake
-                   cmake/QtBaseTopLevelHelpers.cmake
-                   cmake/QtBuild.cmake
-                   cmake/QtBuildHelpers.cmake
-                   cmake/QtBuildOptionsHelpers.cmake
-                   cmake/QtBuildPathsHelpers.cmake
-                   cmake/QtBuildInformation.cmake
-                   cmake/QtBuildRepoExamplesHelpers.cmake
-                   cmake/QtBuildRepoHelpers.cmake
-                   cmake/QtCMakeHelpers.cmake
-                   cmake/QtCMakeVersionHelpers.cmake
-                   cmake/QtCMakePackageVersionFile.cmake.in
-                   cmake/QtCompilerFlags.cmake
-                   cmake/QtCompilerOptimization.cmake
-                   cmake/QtConfigDependencies.cmake.in
-                   cmake/QtConfigureTimeExecutableCMakeLists.txt.in
-                   cmake/QtDeferredDependenciesHelpers.cmake
-                   cmake/QtDbusHelpers.cmake
-                   cmake/QtDocsHelpers.cmake
-                   cmake/QtExecutableHelpers.cmake
-                   cmake/QtFileConfigure.txt.in
-                   cmake/QtFindPackageHelpers.cmake
-                   cmake/QtFindWrapConfigExtra.cmake.in
-                   cmake/QtFindWrapHelper.cmake
-                   cmake/QtFinishPkgConfigFile.cmake
-                   cmake/QtFinishPrlFile.cmake
-                   cmake/QtFlagHandlingHelpers.cmake
-                   cmake/QtFrameworkHelpers.cmake
-                   cmake/QtGenerateExtPri.cmake
-                   cmake/QtGenerateLibHelpers.cmake
-                   cmake/QtGenerateLibPri.cmake
-                   cmake/QtGenerateVersionScript.cmake
-                   cmake/QtGlobalStateHelpers.cmake
-                   cmake/QtHeadersClean.cmake
-                   cmake/QtInstallHelpers.cmake
-                   cmake/QtJavaHelpers.cmake
-                   cmake/QtLalrHelpers.cmake
-                   cmake/QtMkspecHelpers.cmake
-                   cmake/QtModuleConfig.cmake.in
-                   cmake/QtModuleDependencies.cmake.in
-                   cmake/QtModuleHeadersCheck.cmake
-                   cmake/QtModuleHelpers.cmake
-                   cmake/QtModuleToolsConfig.cmake.in
-                   cmake/QtModuleToolsDependencies.cmake.in
-                   cmake/QtModuleToolsVersionlessTargets.cmake.in
-                   cmake/QtNoLinkTargetHelpers.cmake
-                   cmake/QtPkgConfigHelpers.cmake
-                   cmake/QtPlatformAndroid.cmake
-                   cmake/QtPlatformSupport.cmake
-                   cmake/QtPluginConfig.cmake.in
-                   cmake/QtPluginDependencies.cmake.in
-                   cmake/QtPluginHelpers.cmake
-                   cmake/QtPlugins.cmake.in
-                   cmake/QtPostProcess.cmake
-                   cmake/QtPostProcessHelpers.cmake
-                   cmake/QtPrecompiledHeadersHelpers.cmake
-                   cmake/QtUnityBuildHelpers.cmake
-                   cmake/QtPriHelpers.cmake
-                   cmake/QtPrlHelpers.cmake
-                   cmake/QtPlatformTargetHelpers.cmake
-                   cmake/QtProcessConfigureArgs.cmake
-                   cmake/QtQmakeHelpers.cmake
-                   cmake/QtResourceHelpers.cmake
-                   cmake/QtRpathHelpers.cmake
-                   cmake/QtSanitizerHelpers.cmake
-                   cmake/QtScopeFinalizerHelpers.cmake
-                   cmake/QtSeparateDebugInfo.Info.plist.in
-                   cmake/QtSeparateDebugInfo.cmake
-                   cmake/QtSetup.cmake
-                   cmake/QtSimdHelpers.cmake
-                   cmake/QtSingleRepoTargetSetBuildHelpers.cmake
-                   cmake/QtStandaloneTestsConfig.cmake.in
-                   cmake/QtSyncQtHelpers.cmake
-                   cmake/QtTargetHelpers.cmake
-                   cmake/QtTestHelpers.cmake
-                   cmake/QtToolchainHelpers.cmake
-                   cmake/QtToolHelpers.cmake
-                   cmake/QtWasmHelpers.cmake
-                   cmake/QtWrapperScriptHelpers.cmake
-                   cmake/QtWriteArgsFile.cmake
-                   cmake/modulecppexports.h.in
-                   cmake/modulecppexports_p.h.in
-                   cmake/qbatchedtestrunner.in.cpp
+                   ${__private_files}
     DESTINATION "${__GlobalConfig_install_dir}"
 )
 
@@ -328,40 +256,29 @@ if(QT_WILL_INSTALL)
     endforeach()
 endif()
 
+# Wrap previously queried helpers file.
+list(TRANSFORM __qt_cmake_public_helpers PREPEND "cmake/")
+list(TRANSFORM __qt_cmake_public_helpers APPEND ".cmake")
+
+qt_internal_get_qt_build_public_files_to_install(__qt_public_files_to_install)
+list(TRANSFORM __qt_public_files_to_install PREPEND "cmake/")
+
 # Install public CMake files.
 # The functions defined inside can be used in both public projects and while building Qt.
 # Usually we put such functions into Qt6CoreMacros.cmake, but that's getting bloated.
 # These files will be included by Qt6Config.cmake.
-set(__public_cmake_helpers
-    cmake/QtCopyFileIfDifferent.cmake
-    cmake/QtFeature.cmake
-    cmake/QtFeatureCommon.cmake
-    cmake/QtInitProject.cmake
-    cmake/QtPublicAppleHelpers.cmake
-    cmake/QtPublicCMakeHelpers.cmake
-    cmake/QtPublicCMakeVersionHelpers.cmake
-    cmake/QtPublicExternalProjectHelpers.cmake
-    cmake/QtPublicFinalizerHelpers.cmake
-    cmake/QtPublicPluginHelpers.cmake
-    cmake/QtPublicTargetHelpers.cmake
-    cmake/QtPublicTestHelpers.cmake
-    cmake/QtPublicToolHelpers.cmake
-    cmake/QtPublicWalkLibsHelpers.cmake
-    cmake/QtPublicFindPackageHelpers.cmake
-    cmake/QtPublicDependencyHelpers.cmake
-
-    # Public CMake files that are installed next Qt6Config.cmake, but are NOT included by it.
-    # Instead they are included by the generated CMake toolchain file.
-    cmake/QtPublicWasmToolchainHelpers.cmake
+set(__public_files
+    ${__qt_cmake_public_helpers}
+    ${__qt_public_files_to_install}
 )
 
-qt_copy_or_install(FILES ${__public_cmake_helpers} DESTINATION "${__GlobalConfig_install_dir}")
+qt_copy_or_install(FILES ${__public_files} DESTINATION "${__GlobalConfig_install_dir}")
 
 # In prefix builds we also need to copy the files into the build config directory, so that the
 # build-dir Qt6Config.cmake finds the files when building examples in-tree.
 if(QT_WILL_INSTALL)
-    foreach(_public_cmake_helper ${__public_cmake_helpers})
-        file(COPY "${_public_cmake_helper}" DESTINATION "${__GlobalConfig_build_dir}")
+    foreach(_public_file ${__public_files})
+        file(COPY "${_public_file}" DESTINATION "${__GlobalConfig_build_dir}")
     endforeach()
 endif()
 
diff --git a/cmake/QtBuildHelpers.cmake b/cmake/QtBuildHelpers.cmake
index 5abc1ad798..2da1155a84 100644
--- a/cmake/QtBuildHelpers.cmake
+++ b/cmake/QtBuildHelpers.cmake
@@ -120,76 +120,186 @@ macro(qt_internal_set_debug_extend_target)
     option(QT_CMAKE_DEBUG_EXTEND_TARGET "Debug extend_target calls in Qt's build system" OFF)
 endmacro()
 
+# These upstream CMake modules will be automatically include()'d when doing
+# find_package(Qt6 COMPONENTS BuildInternals).
+function(qt_internal_get_qt_build_upstream_cmake_modules out_var)
+    set(${out_var}
+        CMakeFindBinUtils
+        CMakePackageConfigHelpers
+        CheckCXXSourceCompiles
+        FeatureSummary
+        PARENT_SCOPE
+    )
+endfunction()
+
+# These helpers will be installed when building qtbase, and they will be automatically include()'d
+# when doing find_package(Qt6 COMPONENTS BuildInternals).
+# The helpers are expected to exist under the qtbase/cmake sub-directory and their file name
+# extension should be '.cmake'.
+function(qt_internal_get_qt_build_private_helpers out_var)
+    set(${out_var}
+        Qt3rdPartyLibraryHelpers
+        QtAndroidHelpers
+        QtAppHelpers
+        QtAutogenHelpers
+        QtBuildInformation
+        QtBuildOptionsHelpers
+        QtBuildPathsHelpers
+        QtBuildRepoExamplesHelpers
+        QtBuildRepoHelpers
+        QtCMakeHelpers
+        QtCMakeVersionHelpers
+        QtDbusHelpers
+        QtDeferredDependenciesHelpers
+        QtDocsHelpers
+        QtExecutableHelpers
+        QtFindPackageHelpers
+        QtFlagHandlingHelpers
+        QtFrameworkHelpers
+        QtGlobalStateHelpers
+        QtHeadersClean
+        QtInstallHelpers
+        QtJavaHelpers
+        QtLalrHelpers
+        QtMkspecHelpers
+        QtModuleHelpers
+        QtNoLinkTargetHelpers
+        QtPkgConfigHelpers
+        QtPlatformTargetHelpers
+        QtPluginHelpers
+        QtPostProcessHelpers
+        QtPrecompiledHeadersHelpers
+        QtPriHelpers
+        QtPrlHelpers
+        QtQmakeHelpers
+        QtResourceHelpers
+        QtRpathHelpers
+        QtSanitizerHelpers
+        QtScopeFinalizerHelpers
+        QtSeparateDebugInfo
+        QtSimdHelpers
+        QtSingleRepoTargetSetBuildHelpers
+        QtSyncQtHelpers
+        QtTargetHelpers
+        QtTestHelpers
+        QtToolHelpers
+        QtToolchainHelpers
+        QtUnityBuildHelpers
+        QtWasmHelpers
+        QtWrapperScriptHelpers
+        PARENT_SCOPE
+    )
+endfunction()
+
+# These files will be installed when building qtbase, but will NOT be automatically include()d
+# when doing find_package(Qt6 COMPONENTS BuildInternals).
+# The files are expected to exist under the qtbase/cmake sub-directory.
+function(qt_internal_get_qt_build_private_files_to_install out_var)
+    set(${out_var}
+        ModuleDescription.json.in
+        PkgConfigLibrary.pc.in
+        Qt3rdPartyLibraryConfig.cmake.in
+        QtBaseTopLevelHelpers.cmake
+        QtBuild.cmake
+        QtBuildHelpers.cmake
+        QtCMakePackageVersionFile.cmake.in
+        QtCompilerFlags.cmake
+        QtCompilerOptimization.cmake
+        QtConfigDependencies.cmake.in
+        QtConfigureTimeExecutableCMakeLists.txt.in
+        QtFileConfigure.txt.in
+        QtFindWrapConfigExtra.cmake.in
+        QtFindWrapHelper.cmake
+        QtFinishPkgConfigFile.cmake
+        QtFinishPrlFile.cmake
+        QtGenerateExtPri.cmake
+        QtGenerateLibHelpers.cmake
+        QtGenerateLibPri.cmake
+        QtGenerateVersionScript.cmake
+        QtModuleConfig.cmake.in
+        QtModuleDependencies.cmake.in
+        QtModuleHeadersCheck.cmake
+        QtModuleToolsConfig.cmake.in
+        QtModuleToolsDependencies.cmake.in
+        QtModuleToolsVersionlessTargets.cmake.in
+        QtPlatformAndroid.cmake
+        QtPlatformSupport.cmake
+        QtPluginConfig.cmake.in
+        QtPluginDependencies.cmake.in
+        QtPlugins.cmake.in
+        QtPostProcess.cmake
+        QtProcessConfigureArgs.cmake
+        QtSeparateDebugInfo.Info.plist.in
+        QtSetup.cmake
+        QtStandaloneTestsConfig.cmake.in
+        QtWriteArgsFile.cmake
+        modulecppexports.h.in
+        modulecppexports_p.h.in
+        qbatchedtestrunner.in.cpp
+        PARENT_SCOPE
+    )
+endfunction()
+
+# These helpers will be installed when building qtbase, and they will be automatically include()'d
+# when doing find_package(Qt6 COMPONENTS BuildInternals).
+# The helpers are expected to exist under the qtbase/cmake sub-directory and their file name
+# extension should be '.cmake'.
+# In addition, they are meant to be included when doing find_package(Qt6) as well.
+function(qt_internal_get_qt_build_public_helpers out_var)
+    set(${out_var}
+        QtFeature
+        QtFeatureCommon
+        QtPublicAppleHelpers
+        QtPublicCMakeHelpers
+        QtPublicCMakeVersionHelpers
+        QtPublicDependencyHelpers
+        QtPublicExternalProjectHelpers
+        QtPublicFinalizerHelpers
+        QtPublicFindPackageHelpers
+        QtPublicPluginHelpers
+        QtPublicTargetHelpers
+        QtPublicTestHelpers
+        QtPublicToolHelpers
+        QtPublicWalkLibsHelpers
+        PARENT_SCOPE
+    )
+endfunction()
+
+# These files will be installed when building qtbase, but will NOT be automatically include()d
+# when doing find_package(Qt6) nor find_package(Qt6 COMPONENTS BuildInternals).
+# The files are expected to exist under the qtbase/cmake sub-directory.
+function(qt_internal_get_qt_build_public_files_to_install out_var)
+    set(${out_var}
+        QtCopyFileIfDifferent.cmake
+        QtInitProject.cmake
+
+        # Public CMake files that are installed next Qt6Config.cmake, but are NOT included by it.
+        # Instead they are included by the generated CMake toolchain file.
+        QtPublicWasmToolchainHelpers.cmake
+
+        PARENT_SCOPE
+    )
+endfunction()
+
+# Includes all Qt CMake helper files that define functions and macros.
 macro(qt_internal_include_all_helpers)
     # Upstream cmake modules.
-    include(CheckCXXSourceCompiles)
-    include(CMakeFindBinUtils)
-    include(CMakePackageConfigHelpers)
-    include(FeatureSummary)
+    qt_internal_get_qt_build_upstream_cmake_modules(__qt_upstream_helpers)
+    foreach(__qt_file_name IN LISTS __qt_upstream_helpers)
+        include("${__qt_file_name}")
+    endforeach()
 
     # Internal helpers available only while building Qt itself.
-    include(Qt3rdPartyLibraryHelpers)
-    include(QtAndroidHelpers)
-    include(QtAppHelpers)
-    include(QtAutogenHelpers)
-    include(QtBuildInformation)
-    include(QtBuildOptionsHelpers)
-    include(QtBuildPathsHelpers)
-    include(QtBuildRepoExamplesHelpers)
-    include(QtBuildRepoHelpers)
-    include(QtCMakeHelpers)
-    include(QtCMakeVersionHelpers)
-    include(QtDbusHelpers)
-    include(QtDeferredDependenciesHelpers)
-    include(QtDocsHelpers)
-    include(QtExecutableHelpers)
-    include(QtFeature)
-    include(QtFindPackageHelpers)
-    include(QtFlagHandlingHelpers)
-    include(QtFrameworkHelpers)
-    include(QtGlobalStateHelpers)
-    include(QtHeadersClean)
-    include(QtInstallHelpers)
-    include(QtJavaHelpers)
-    include(QtLalrHelpers)
-    include(QtMkspecHelpers)
-    include(QtModuleHelpers)
-    include(QtNoLinkTargetHelpers)
-    include(QtPkgConfigHelpers)
-    include(QtPlatformTargetHelpers)
-    include(QtPluginHelpers)
-    include(QtPostProcessHelpers)
-    include(QtPrecompiledHeadersHelpers)
-    include(QtPriHelpers)
-    include(QtPrlHelpers)
-    include(QtQmakeHelpers)
-    include(QtResourceHelpers)
-    include(QtRpathHelpers)
-    include(QtSanitizerHelpers)
-    include(QtScopeFinalizerHelpers)
-    include(QtSeparateDebugInfo)
-    include(QtSimdHelpers)
-    include(QtSingleRepoTargetSetBuildHelpers)
-    include(QtSyncQtHelpers)
-    include(QtTargetHelpers)
-    include(QtTestHelpers)
-    include(QtToolchainHelpers)
-    include(QtToolHelpers)
-    include(QtUnityBuildHelpers)
-    include(QtWasmHelpers)
-    include(QtWrapperScriptHelpers)
+    qt_internal_get_qt_build_private_helpers(__qt_private_helpers)
+    foreach(__qt_file_name IN LISTS __qt_private_helpers)
+        include("${__qt_file_name}")
+    endforeach()
 
     # Helpers that are available in public projects and while building Qt itself.
-    include(QtPublicAppleHelpers)
-    include(QtPublicCMakeHelpers)
-    include(QtPublicDependencyHelpers)
-    include(QtPublicExternalProjectHelpers)
-    include(QtPublicFindPackageHelpers)
-    include(QtPublicPluginHelpers)
-    include(QtPublicTargetHelpers)
-    include(QtPublicTestHelpers)
-    include(QtPublicToolHelpers)
-    include(QtPublicWalkLibsHelpers)
+    qt_internal_get_qt_build_public_helpers(__qt_public_helpers)
+    foreach(__qt_file_name IN LISTS __qt_public_helpers)
+        include("${__qt_file_name}")
+    endforeach()
 endmacro()
 
 function(qt_internal_check_host_path_set_for_cross_compiling)
diff --git a/cmake/QtConfig.cmake.in b/cmake/QtConfig.cmake.in
index 67fde7f05f..28a1cb8bc1 100644
--- a/cmake/QtConfig.cmake.in
+++ b/cmake/QtConfig.cmake.in
@@ -38,18 +38,12 @@ if(APPLE)
 endif()
 
 # Public helpers available to all Qt packages.
-include("${CMAKE_CURRENT_LIST_DIR}/QtFeature.cmake")
-include("${CMAKE_CURRENT_LIST_DIR}/QtPublicAppleHelpers.cmake")
-include("${CMAKE_CURRENT_LIST_DIR}/QtPublicExternalProjectHelpers.cmake")
-include("${CMAKE_CURRENT_LIST_DIR}/QtPublicFinalizerHelpers.cmake")
-include("${CMAKE_CURRENT_LIST_DIR}/QtPublicPluginHelpers.cmake")
-include("${CMAKE_CURRENT_LIST_DIR}/QtPublicTargetHelpers.cmake")
-include("${CMAKE_CURRENT_LIST_DIR}/QtPublicWalkLibsHelpers.cmake")
-include("${CMAKE_CURRENT_LIST_DIR}/QtPublicFindPackageHelpers.cmake")
-include("${CMAKE_CURRENT_LIST_DIR}/QtPublicDependencyHelpers.cmake")
-include("${CMAKE_CURRENT_LIST_DIR}/QtPublicTestHelpers.cmake")
-include("${CMAKE_CURRENT_LIST_DIR}/QtPublicToolHelpers.cmake")
-include("${CMAKE_CURRENT_LIST_DIR}/QtPublicCMakeHelpers.cmake")
+set(__qt_public_files_to_include
+    @QT_PUBLIC_FILES_TO_INCLUDE@
+)
+foreach(__qt_public_file_to_include IN LISTS __qt_public_files_to_include)
+    include("${__qt_public_file_to_include}")
+endforeach()
 
 set(QT_ADDITIONAL_PACKAGES_PREFIX_PATH "" CACHE STRING
     "Additional directories where find(Qt6 ...) components are searched")
diff --git a/cmake/QtFeature.cmake b/cmake/QtFeature.cmake
index 6bce87e59a..730f80ce95 100644
--- a/cmake/QtFeature.cmake
+++ b/cmake/QtFeature.cmake
@@ -1,7 +1,6 @@
 # Copyright (C) 2022 The Qt Company Ltd.
 # SPDX-License-Identifier: BSD-3-Clause
 
-include(QtFeatureCommon)
 include(CheckCXXCompilerFlag)
 
 function(qt_feature_module_begin)