CMake: Set versioned variables with found modules, plugins, types

Introduce two new directory-scoped variables containing versioned
(prefixed with Qt6::) target names of qt modules and qt plugins found
as a result of finding Qt packages:
- QT_ALL_MODULES_VERSIONED_FOUND_VIA_FIND_PACKAGE
- QT_ALL_PLUGINS_VERSIONED_FOUND_VIA_FIND_PACKAGE

To be consistent in the naming of the variables going forward,
deprecate the old QT_ALL_PLUGINS_FOUND_BY_FIND_PACKAGE variable
in favor of a new QT_ALL_PLUGINS_FOUND_VIA_FIND_PACKAGE.
The difference is 'BY' vs 'VIA'.

The non-versioned variables are modified not to contain duplicates:
- QT_ALL_MODULES_FOUND_VIA_FIND_PACKAGE
- QT_ALL_PLUGINS_FOUND_VIA_FIND_PACKAGE

Also remove duplicates from the variable that collects all found qt
plugin types:
- QT_ALL_PLUGIN_TYPES_FOUND_VIA_FIND_PACKAGE

A follow-up change will collect qml plugin targets.

This information can be useful to find out what Qt targets are
available in a project, for example to know what plugin targets or
types can be linked into another target, or which libraries can be
deployed.

Pick-to: 6.8 6.9
Change-Id: I4f158872f4a8f6ef6008f081270604f75b77ad9d
Reviewed-by: Joerg Bornemann <[email protected]>

2 files changed, 39 insertions, 5 deletions

diff --git a/cmake/QtModuleConfig.cmake.in b/cmake/QtModuleConfig.cmake.in
index de243aff2b3..cd6c3427a37 100644
--- a/cmake/QtModuleConfig.cmake.in
+++ b/cmake/QtModuleConfig.cmake.in
@@ -167,18 +167,28 @@ if (TARGET @QT_CMAKE_EXPORT_NAMESPACE@::@target@)
         include("${CMAKE_CURRENT_LIST_DIR}/@INSTALL_CMAKE_NAMESPACE@@[email protected]")
     endif()
 
-    list(APPEND QT_ALL_MODULES_FOUND_VIA_FIND_PACKAGE "@target@")
+    if(NOT "@target@" IN_LIST QT_ALL_MODULES_FOUND_VIA_FIND_PACKAGE)
+        list(APPEND QT_ALL_MODULES_FOUND_VIA_FIND_PACKAGE "@target@")
+        list(APPEND QT_ALL_MODULES_VERSIONED_FOUND_VIA_FIND_PACKAGE
+            "@INSTALL_CMAKE_NAMESPACE@::@target@")
+    endif()
 
     get_target_property(_qt_module_target_type "@INSTALL_CMAKE_NAMESPACE@::@target@" TYPE)
     if(NOT _qt_module_target_type STREQUAL "INTERFACE_LIBRARY")
         get_target_property(_qt_module_plugin_types
                             @INSTALL_CMAKE_NAMESPACE@::@target@ MODULE_PLUGIN_TYPES)
         if(_qt_module_plugin_types)
-            list(APPEND QT_ALL_PLUGIN_TYPES_FOUND_VIA_FIND_PACKAGE "${_qt_module_plugin_types}")
+            foreach(_qt_module_plugin_type IN LISTS _qt_module_plugin_types)
+                if(NOT "${_qt_module_plugin_type}"
+                    IN_LIST QT_ALL_PLUGIN_TYPES_FOUND_VIA_FIND_PACKAGE)
+                    list(APPEND QT_ALL_PLUGIN_TYPES_FOUND_VIA_FIND_PACKAGE
+                    "${_qt_module_plugin_type}")
+                endif()
+            endforeach()
+            unset(_qt_module_plugin_type)
         endif()
     endif()
 
-
     # Load Module's BuildInternals should any exist
     if (@INSTALL_CMAKE_NAMESPACE@BuildInternals_DIR AND
         EXISTS "${CMAKE_CURRENT_LIST_DIR}/@INSTALL_CMAKE_NAMESPACE@@[email protected]")
diff --git a/cmake/QtPublicPluginHelpers.cmake b/cmake/QtPublicPluginHelpers.cmake
index 3a9f18d797f..055f50711f2 100644
--- a/cmake/QtPublicPluginHelpers.cmake
+++ b/cmake/QtPublicPluginHelpers.cmake
@@ -581,10 +581,34 @@ macro(__qt_internal_include_plugin_packages target)
             continue()
         endif()
 
-        list(APPEND "QT_ALL_PLUGINS_FOUND_BY_FIND_PACKAGE_${__plugin_type}" "${plugin_target}")
+        set(plugin_target_versioned "${QT_CMAKE_EXPORT_NAMESPACE}::${plugin_target}")
+
+        if(NOT "${plugin_target}"
+                IN_LIST QT_ALL_PLUGINS_FOUND_VIA_FIND_PACKAGE)
+
+            # Old compatibility name.
+            # TODO: Remove once all usages are ported.
+            list(APPEND QT_ALL_PLUGINS_FOUND_BY_FIND_PACKAGE "${plugin_target}")
+
+            # New name consistent with other such variables.
+            list(APPEND QT_ALL_PLUGINS_FOUND_VIA_FIND_PACKAGE "${plugin_target}")
+            list(APPEND QT_ALL_PLUGINS_VERSIONED_FOUND_VIA_FIND_PACKAGE
+                "${plugin_target_versioned}")
+        endif()
+
+        if(NOT "${plugin_target}" IN_LIST QT_ALL_PLUGINS_FOUND_VIA_FIND_PACKAGE_${__plugin_type})
+            # Old compatibility name.
+            # TODO: Remove once all usages are ported.
+            list(APPEND QT_ALL_PLUGINS_FOUND_BY_FIND_PACKAGE_${__plugin_type} "${plugin_target}")
+
+            # New name consistent with other such variables.
+            list(APPEND QT_ALL_PLUGINS_FOUND_VIA_FIND_PACKAGE_${__plugin_type} "${plugin_target}")
+            list(APPEND
+                QT_ALL_PLUGINS_VERSIONED_FOUND_VIA_FIND_PACKAGE_${__plugin_type}
+                "${plugin_target_versioned}")
+        endif()
 
         # Auto-linkage should be set up only for static plugins.
-        set(plugin_target_versioned "${QT_CMAKE_EXPORT_NAMESPACE}::${plugin_target}")
         get_target_property(type "${plugin_target_versioned}" TYPE)
         if(type STREQUAL STATIC_LIBRARY)
             __qt_internal_add_static_plugin_linkage(