From 5ffc06d5e735fcf9bdf5b92874292bccc88acd28 Mon Sep 17 00:00:00 2001
From: Andreas Sturmlechner <asturm@gentoo.org>
Date: Mon, 14 Apr 2025 22:50:08 +0200
Subject: [PATCH] CMake: Make translations optional

 - Use FeatureSummary to list found dependencies in CMake output
 - Make it possible to build without translations by making LinguistTools optional
 - When Qt5LinguistTools is optional, then qtpaths would remain as a rather costly dependency on Qt5Tools just to establish PLUGINDIR
   Hence allow distributions/users to set PLUGINDIR manually and only fallback to qtpaths if not set
 - Lowercase some cmake commands for consistency
 - Append `src` to source directory when generating translations, otherwise build directories could be parsed too

(partially cherry-picked from qt6ct 66c08b191b15ab71b206c3bbea4dcb19a26ab874)

Thanks-to: Jonas Kvinge <jonas@jkvinge.net>
Signed-off-by: Andreas Sturmlechner <asturm@gentoo.org>
---
 CMakeLists.txt           | 45 +++++++++++++++++++++-------------------
 src/qt5ct/CMakeLists.txt |  5 ++++-
 2 files changed, 28 insertions(+), 22 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 59256fd..814757e 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -3,13 +3,14 @@ cmake_minimum_required(VERSION 3.11.0)
 project(qt5ct LANGUAGES CXX)
 
 include(GNUInstallDirs)
+include(FeatureSummary)
 
-CONFIGURE_FILE(
+configure_file(
   "${CMAKE_CURRENT_SOURCE_DIR}/cmake_uninstall.cmake.in"
   "${CMAKE_CURRENT_BINARY_DIR}/cmake_uninstall.cmake"
   IMMEDIATE @ONLY)
 
-ADD_CUSTOM_TARGET(uninstall
+add_custom_target(uninstall
   "${CMAKE_COMMAND}" -P "${CMAKE_CURRENT_BINARY_DIR}/cmake_uninstall.cmake")
 
 set(CMAKE_CXX_STANDARD 11)
@@ -25,9 +26,9 @@ set(QT_MINIMUM_VERSION "5.15.0")
 
 option(DISABLE_DBUS "disable D-Bus support (global menu and D-Bus tray icon implementation)" OFF)
 
-ADD_DEFINITIONS(-DQT_DISABLE_DEPRECATED_BEFORE=0x050C00 -DUSE_WIDGETS)
+add_definitions(-DQT_DISABLE_DEPRECATED_BEFORE=0x050C00 -DUSE_WIDGETS)
 
-find_package(Qt5 ${QT_MINIMUM_VERSION} COMPONENTS Widgets Concurrent LinguistTools REQUIRED)
+find_package(Qt5 ${QT_MINIMUM_VERSION} REQUIRED COMPONENTS Core Widgets Concurrent OPTIONAL_COMPONENTS LinguistTools)
 find_package(Qt5Gui ${QT_MINIMUM_VERSION} CONFIG REQUIRED Private)
 
 if(NOT DISABLE_DBUS)
@@ -37,29 +38,29 @@ else()
     message(STATUS "D-Bus support: Disabled")
 endif()
 
-get_target_property(QT_LRELEASE_EXECUTABLE Qt5::lrelease IMPORTED_LOCATION)
-
-if(QT_LRELEASE_EXECUTABLE)
-    message(STATUS "Found lrelease executable: " ${QT_LRELEASE_EXECUTABLE})
-else()
-    message(FATAL_ERROR "Could NOT find lrelease executable")
+if(Qt5LinguistTools_FOUND)
+    message(STATUS "Generating translations ...")
+    get_target_property(QT_LRELEASE_EXECUTABLE Qt5::lrelease IMPORTED_LOCATION)
+    execute_process(COMMAND find ${CMAKE_CURRENT_SOURCE_DIR}/src -name *.ts COMMAND xargs ${QT_LRELEASE_EXECUTABLE} -silent)
 endif()
 
-get_filename_component(QT_QTPATHS_EXECUTABLE ${QT_LRELEASE_EXECUTABLE} DIRECTORY)
-set(QT_QTPATHS_EXECUTABLE ${QT_QTPATHS_EXECUTABLE}/qtpaths)
+if(Qt5LinguistTools_FOUND AND NOT PLUGINDIR)
+    get_filename_component(QT_QTPATHS_EXECUTABLE ${QT_LRELEASE_EXECUTABLE} DIRECTORY)
+    set(QT_QTPATHS_EXECUTABLE ${QT_QTPATHS_EXECUTABLE}/qtpaths)
 
-if(EXISTS ${QT_QTPATHS_EXECUTABLE})
-    message(STATUS "Found qtpaths executable: " ${QT_QTPATHS_EXECUTABLE})
-else()
-    message(FATAL_ERROR "Could NOT find qtpaths executable")
+    if(EXISTS ${QT_QTPATHS_EXECUTABLE})
+        message(STATUS "Found qtpaths executable: " ${QT_QTPATHS_EXECUTABLE})
+    else()
+        message(FATAL_ERROR "Could NOT find qtpaths executable")
+    endif()
+
+    execute_process(COMMAND ${QT_QTPATHS_EXECUTABLE} --plugin-dir OUTPUT_VARIABLE PLUGINDIR OUTPUT_STRIP_TRAILING_WHITESPACE)
+elseif(NOT Qt5LinguistTools_FOUND AND NOT PLUGINDIR)
+    message(FATAL_ERROR "PLUGINDIR not provided and Qt5LinguistTools not found - aborting.")
 endif()
 
-execute_process(COMMAND ${QT_QTPATHS_EXECUTABLE} --plugin-dir OUTPUT_VARIABLE PLUGINDIR OUTPUT_STRIP_TRAILING_WHITESPACE)
 message(STATUS "Plugin path: " ${PLUGINDIR})
 
-message(STATUS "Generating translations ...")
-execute_process(COMMAND find ${CMAKE_CURRENT_SOURCE_DIR} -name *.ts COMMAND xargs ${QT_LRELEASE_EXECUTABLE} -silent)
-
 include_directories(${CMAKE_CURRENT_SOURCE_DIR}/src/qt5ct-common)
 
 add_link_options(-Wl,--no-undefined)
@@ -108,4 +109,6 @@ if(UNIX)
         ARGS -rf ${CMAKE_CURRENT_BINARY_DIR}/doc/html
         TARGET distclean
     )
-endif(UNIX)
+endif()
+
+feature_summary(WHAT ALL FATAL_ON_MISSING_REQUIRED_PACKAGES)
diff --git a/src/qt5ct/CMakeLists.txt b/src/qt5ct/CMakeLists.txt
index 78535e3..3249e21 100644
--- a/src/qt5ct/CMakeLists.txt
+++ b/src/qt5ct/CMakeLists.txt
@@ -24,9 +24,12 @@ set(app_SRCS
   qsseditordialog.ui
   qsspage.ui
   troubleshootingpage.ui
-  translations/translations.qrc
 )
 
+if(Qt5LinguistTools_FOUND)
+  list(APPEND app_SRCS translations/translations.qrc)
+endif()
+
 add_executable(qt5ct ${app_SRCS})
 target_link_libraries(qt5ct PRIVATE Qt5::Widgets Qt5::Concurrent Qt5::WidgetsPrivate qt5ct-common)
 install(TARGETS qt5ct DESTINATION ${CMAKE_INSTALL_BINDIR})
-- 
2.49.0