Deprecate Shell::useLayerShell()

it's not needed since Qt 6.5 and can potentially leak the environment
variable.

CMakeLists.txt

@@ -32,6 +32,7 @@ include(KDEClangFormat)
 include(ECMQtDeclareLoggingCategory)
 include(ECMQmlModule)
 include(KDEGitCommitHooks)
+include(ECMGenerateExportHeader)
 
 find_package(Qt6 ${QT_MIN_VERSION} CONFIG REQUIRED COMPONENTS WaylandClient Qml)
 

src/CMakeLists.txt

@@ -64,10 +64,12 @@ ecm_generate_headers(LayerShellQt_HEADERS
 )
 
 
-generate_export_header(LayerShellQtInterface
+ecm_generate_export_header(LayerShellQtInterface
     BASE_NAME LayerShellQtInterface
     EXPORT_MACRO_NAME LAYERSHELLQT_EXPORT
     EXPORT_FILE_NAME LayerShellQt/layershellqt_export.h
+    VERSION ${LAYERSHELLQT_VERSION}
+    DEPRECATION_VERSIONS 6.6
 )
 
 install(TARGETS layer-shell

src/interfaces/shell.cpp

@@ -5,6 +5,9 @@
  */
 
 #include "shell.h"
+
+#if LAYERSHELLQTINTERFACE_BUILD_DEPRECATED_SINCE(6, 6)
+
 #include <QByteArray>
 #include <layershellqt_logging.h>
 #include <qglobal.h>
@@ -18,3 +21,4 @@ void Shell::useLayerShell()
         qCDebug(LAYERSHELLQT) << "Unable to set QT_WAYLAND_SHELL_INTEGRATION=layer-shell";
     }
 }
+#endif

src/interfaces/shell.h

@@ -8,7 +8,9 @@
 #define LAYERSHELLQTSHELL_H
 
 #include "layershellqt_export.h"
-#include "window.h"
+
+#if LAYERSHELLQTINTERFACE_ENABLE_DEPRECATED_SINCE(6, 6)
+
 #include <QString>
 
 namespace LayerShellQt
@@ -19,9 +21,11 @@ namespace LayerShellQt
 class LAYERSHELLQT_EXPORT Shell
 {
 public:
+    LAYERSHELLQTINTERFACE_DEPRECATED_VERSION(6, 6, "Calling useLayerShell is not needed since Qt 6.5")
     static void useLayerShell();
 };
 
 }
+#endif
 
 #endif