Adapt build system to also support building against Qt6

CMakeLists.txt

@@ -18,36 +18,41 @@ include(GenerateExportHeader)
 # where to look first for cmake modules, before ${CMAKE_ROOT}/Modules/ is checked
 set(CMAKE_MODULE_PATH ${CMAKE_CURRENT_SOURCE_DIR}/cmake/modules ${ECM_MODULE_PATH})
 
-find_package(Qt5 ${QT_MIN_VERSION} CONFIG REQUIRED COMPONENTS
+include(KDEInstallDirs)
+include(KDECMakeSettings)
+include(KDECompilerSettings NO_POLICY_SCOPE)
+include(KDEClangFormat)
+
+include(ECMInstallIcons)
+include(ECMOptionalAddSubdirectory)
+include(ECMConfiguredInstall)
+include(ECMQtDeclareLoggingCategory)
+
+find_package(Qt${QT_MAJOR_VERSION} ${QT_MIN_VERSION} CONFIG REQUIRED COMPONENTS
     Concurrent
     Core
     DBus
     Quick
     UiTools
     Widgets
-    X11Extras
 )
+if (QT_MAJOR_VERSION EQUAL "5")
+    find_package(Qt5 ${QT_MIN_VERSION} CONFIG REQUIRED COMPONENTS X11Extras)
+    find_package(Qt5XkbCommonSupport REQUIRED)
+else()
+    find_package(Qt6 ${QT_MIN_VERSION} CONFIG REQUIRED COMPONENTS WaylandClient)
+endif()
 
-find_package(Qt5Test ${QT_MIN_VERSION} CONFIG QUIET)
-set_package_properties(Qt5Test PROPERTIES
+find_package(Qt${QT_MAJOR_VERSION}Test ${QT_MIN_VERSION} CONFIG QUIET)
+set_package_properties(Qt${QT_MAJOR_VERSION}Test PROPERTIES
     PURPOSE "Required for tests"
     TYPE OPTIONAL
 )
-add_feature_info("Qt5Test" Qt5Test_FOUND "Required for building tests")
-if (NOT Qt5Test_FOUND)
+add_feature_info("Qt${QT_MAJOR_VERSION}Test" Qt${QT_MAJOR_VERSION}Test_FOUND "Required for building tests")
+if (NOT Qt${QT_MAJOR_VERSION}Test_FOUND)
     set(BUILD_TESTING OFF CACHE BOOL "Build the testing tree.")
 endif()
 
-include(KDEInstallDirs)
-include(KDECMakeSettings)
-include(KDECompilerSettings NO_POLICY_SCOPE)
-include(KDEClangFormat)
-
-include(ECMInstallIcons)
-include(ECMOptionalAddSubdirectory)
-include(ECMConfiguredInstall)
-include(ECMQtDeclareLoggingCategory)
-
 add_definitions(
     -DQT_DISABLE_DEPRECATED_BEFORE=0
 
@@ -195,8 +200,6 @@ set_package_properties(XKB PROPERTIES
     PURPOSE "Required for building KWin with Wayland support"
 )
 
-find_package(Qt5XkbCommonSupport REQUIRED)
-
 find_package(Libinput 1.19)
 set_package_properties(Libinput PROPERTIES TYPE REQUIRED PURPOSE "Required for input handling on Wayland.")
 
@@ -268,10 +271,12 @@ set_package_properties(X11_XCB PROPERTIES
 )
 
 # dependencies for QPA plugin
-find_package(Qt5FontDatabaseSupport REQUIRED)
-find_package(Qt5ThemeSupport REQUIRED)
-find_package(Qt5ServiceSupport REQUIRED)
-find_package(Qt5EventDispatcherSupport REQUIRED)
+if (QT_MAJOR_VERSION EQUAL "5")
+    find_package(Qt5FontDatabaseSupport REQUIRED)
+    find_package(Qt5ThemeSupport REQUIRED)
+    find_package(Qt5ServiceSupport REQUIRED)
+    find_package(Qt5EventDispatcherSupport REQUIRED)
+endif()
 
 find_package(Freetype REQUIRED)
 set_package_properties(Freetype PROPERTIES
@@ -411,7 +416,9 @@ add_subdirectory(src)
 
 if (BUILD_TESTING)
     find_package(WaylandProtocols 1.19 REQUIRED)
-    find_package(QtWaylandScanner ${QT_MIN_VERSION} REQUIRED)
+    if (QT_MAJOR_VERSION EQUAL "5")
+        find_package(QtWaylandScanner ${QT_MIN_VERSION} REQUIRED)
+    endif()
     find_package(Wayland REQUIRED COMPONENTS Client)
     find_package(PlasmaWaylandProtocols CONFIG REQUIRED)
 

autotests/CMakeLists.txt

@@ -232,8 +232,10 @@ target_link_libraries(testXkb
     kwineffects
 
     XKB::XKB
-    Qt5::XkbCommonSupportPrivate
 )
+if (QT_MAJOR_VERSION EQUAL "5")
+    target_link_libraries(testXkb Qt5::XkbCommonSupportPrivate)
+endif()
 add_test(NAME kwin-testXkb COMMAND testXkb)
 ecm_mark_as_test(testXkb)
 

autotests/integration/CMakeLists.txt

@@ -7,40 +7,54 @@ set(KWinIntegrationTestFramework_SOURCES
     kwin_wayland_test.cpp
     test_helpers.cpp
 )
-ecm_add_qtwayland_client_protocol(KWinIntegrationTestFramework_SOURCES
-    PROTOCOL ${WaylandProtocols_DATADIR}/unstable/input-method/input-method-unstable-v1.xml
-    BASENAME input-method-unstable-v1
-)
-ecm_add_qtwayland_client_protocol(KWinIntegrationTestFramework_SOURCES
-    PROTOCOL ${WaylandProtocols_DATADIR}/unstable/text-input/text-input-unstable-v3.xml
-    BASENAME text-input-unstable-v3
-)
-ecm_add_qtwayland_client_protocol(KWinIntegrationTestFramework_SOURCES
-    PROTOCOL protocols/wlr-layer-shell-unstable-v1.xml
-    BASENAME wlr-layer-shell-unstable-v1
-)
-ecm_add_qtwayland_client_protocol(KWinIntegrationTestFramework_SOURCES
-    PROTOCOL ${WaylandProtocols_DATADIR}/stable/xdg-shell/xdg-shell.xml
-    BASENAME xdg-shell
-)
-ecm_add_qtwayland_client_protocol(KWinIntegrationTestFramework_SOURCES
-    PROTOCOL ${WaylandProtocols_DATADIR}/unstable/xdg-decoration/xdg-decoration-unstable-v1.xml
-    BASENAME xdg-decoration-unstable-v1
-)
-ecm_add_qtwayland_client_protocol(KWinIntegrationTestFramework_SOURCES
-    PROTOCOL ${WaylandProtocols_DATADIR}/unstable/idle-inhibit/idle-inhibit-unstable-v1.xml
-    BASENAME idle-inhibit-unstable-v1
-)
-ecm_add_qtwayland_client_protocol(KWinIntegrationTestFramework_SOURCES
-    PROTOCOL ${PLASMA_WAYLAND_PROTOCOLS_DIR}/kde-output-device-v2.xml
-    BASENAME kde-output-device-v2
-)
-ecm_add_qtwayland_client_protocol(KWinIntegrationTestFramework_SOURCES
-    PROTOCOL ${PLASMA_WAYLAND_PROTOCOLS_DIR}/kde-output-management-v2.xml
-    BASENAME kde-output-management-v2
-)
+add_library(KWinIntegrationTestFramework SHARED)
+if (QT_MAJOR_VERSION EQUAL "5")
+    ecm_add_qtwayland_client_protocol(KWinIntegrationTestFramework_SOURCES
+        PROTOCOL ${WaylandProtocols_DATADIR}/unstable/input-method/input-method-unstable-v1.xml
+        BASENAME input-method-unstable-v1
+    )
+    ecm_add_qtwayland_client_protocol(KWinIntegrationTestFramework_SOURCES
+        PROTOCOL ${WaylandProtocols_DATADIR}/unstable/text-input/text-input-unstable-v3.xml
+        BASENAME text-input-unstable-v3
+    )
+    ecm_add_qtwayland_client_protocol(KWinIntegrationTestFramework_SOURCES
+        PROTOCOL protocols/wlr-layer-shell-unstable-v1.xml
+        BASENAME wlr-layer-shell-unstable-v1
+    )
+    ecm_add_qtwayland_client_protocol(KWinIntegrationTestFramework_SOURCES
+        PROTOCOL ${WaylandProtocols_DATADIR}/stable/xdg-shell/xdg-shell.xml
+        BASENAME xdg-shell
+    )
+    ecm_add_qtwayland_client_protocol(KWinIntegrationTestFramework_SOURCES
+        PROTOCOL ${WaylandProtocols_DATADIR}/unstable/xdg-decoration/xdg-decoration-unstable-v1.xml
+        BASENAME xdg-decoration-unstable-v1
+    )
+    ecm_add_qtwayland_client_protocol(KWinIntegrationTestFramework_SOURCES
+        PROTOCOL ${WaylandProtocols_DATADIR}/unstable/idle-inhibit/idle-inhibit-unstable-v1.xml
+        BASENAME idle-inhibit-unstable-v1
+    )
+    ecm_add_qtwayland_client_protocol(KWinIntegrationTestFramework_SOURCES
+        PROTOCOL ${PLASMA_WAYLAND_PROTOCOLS_DIR}/kde-output-device-v2.xml
+        BASENAME kde-output-device-v2
+    )
+    ecm_add_qtwayland_client_protocol(KWinIntegrationTestFramework_SOURCES
+        PROTOCOL ${PLASMA_WAYLAND_PROTOCOLS_DIR}/kde-output-management-v2.xml
+        BASENAME kde-output-management-v2
+    )
+else()
+    qt6_generate_wayland_protocol_client_sources(KWinIntegrationTestFramework FILES
+        ${WaylandProtocols_DATADIR}/unstable/input-method/input-method-unstable-v1.xml
+        ${WaylandProtocols_DATADIR}/unstable/text-input/text-input-unstable-v3.xml
+        ${CMAKE_CURRENT_SOURCE_DIR}/protocols/wlr-layer-shell-unstable-v1.xml
+        ${WaylandProtocols_DATADIR}/stable/xdg-shell/xdg-shell.xml
+        ${WaylandProtocols_DATADIR}/unstable/xdg-decoration/xdg-decoration-unstable-v1.xml
+        ${WaylandProtocols_DATADIR}/unstable/idle-inhibit/idle-inhibit-unstable-v1.xml
+        ${PLASMA_WAYLAND_PROTOCOLS_DIR}/kde-output-device-v2.xml
+        ${PLASMA_WAYLAND_PROTOCOLS_DIR}/kde-output-management-v2.xml
+    )
+endif()
 
-add_library(KWinIntegrationTestFramework SHARED ${KWinIntegrationTestFramework_SOURCES})
+target_sources(KWinIntegrationTestFramework PRIVATE ${KWinIntegrationTestFramework_SOURCES})
 target_link_libraries(KWinIntegrationTestFramework
     PUBLIC
         Qt::Test

src/CMakeLists.txt

@@ -200,11 +200,13 @@ target_link_libraries(kwin
 
     UDev::UDev
     XKB::XKB
-    Qt5::XkbCommonSupportPrivate
     epoxy::epoxy
 
     Threads::Threads
 )
+if (QT_MAJOR_VERSION EQUAL "5")
+    target_link_libraries(kwin Qt5::XkbCommonSupportPrivate)
+endif()
 
 if (KWIN_BUILD_NOTIFICATIONS)
     target_link_libraries(kwin KF5::Notifications)

src/libkwineffects/KWinEffectsConfig.cmake.in

@@ -1,8 +1,8 @@
 @PACKAGE_INIT@
 
 include(CMakeFindDependencyMacro)
-find_dependency(Qt5Core "@QT_MIN_VERSION@")
-find_dependency(Qt5Gui "@QT_MIN_VERSION@")
+find_dependency(Qt@QT_MAJOR_VERSION@Core "@QT_MIN_VERSION@")
+find_dependency(Qt@QT_MAJOR_VERSION@Gui "@QT_MIN_VERSION@")
 find_dependency(KF5Config "@KF5_MIN_VERSION@")
 find_dependency(KF5CoreAddons "@KF5_MIN_VERSION@")
 find_dependency(KF5WindowSystem "@KF5_MIN_VERSION@")

src/plugins/qpa/CMakeLists.txt

@@ -23,11 +23,15 @@ target_compile_definitions(KWinQpaPlugin PRIVATE QT_STATICPLUGIN)
 target_link_libraries(KWinQpaPlugin PRIVATE
     Qt::CorePrivate
     Qt::GuiPrivate
-    Qt::FontDatabaseSupportPrivate
-    Qt::ThemeSupportPrivate
-    Qt::EventDispatcherSupportPrivate
-    Qt::ServiceSupportPrivate
     Freetype::Freetype # Must be after Qt5 platform support libs
     Fontconfig::Fontconfig
     kwin
 )
+if (QT_MAJOR_VERSION EQUAL "5")
+    target_link_libraries(KWinQpaPlugin PRIVATE
+        Qt::FontDatabaseSupportPrivate
+        Qt::ThemeSupportPrivate
+        Qt::EventDispatcherSupportPrivate
+        Qt::ServiceSupportPrivate
+    )
+endif()