add skeleton python plugin

I think it makes sense to start the work on an interpreter
inside a plugin

that did work in the past for the old python scripting,
too

addons/CMakeLists.txt

-ecm_set_disabled_deprecation_versions(
-    QT 5.15
-    KF 5.90
-)
-
 function (kate_add_plugin name)
     kcoreaddons_add_plugin(${name} INSTALL_NAMESPACE "ktexteditor")
 endfunction()
@@ -10,6 +5,16 @@ endfunction()
 # Most plugins will need to link against KF5TextEditor to have access to its plugin interface.
 find_package(KF5TextEditor ${KF5_DEP_VERSION} QUIET REQUIRED)
 
+# python plugin
+if (BUILD_PYTHON_BINDINDS)
+    ecm_optional_add_subdirectory(python)
+endif()
+
+ecm_set_disabled_deprecation_versions(
+    QT 5.15
+    KF 5.90
+)
+
 ecm_optional_add_subdirectory(backtracebrowser)
 ecm_optional_add_subdirectory(close-except-like) # Close all documents except this one (or similar).
 ecm_optional_add_subdirectory(colorpicker) # Inline color preview/picker

addons/python/CMakeLists.txt

+kate_add_plugin(katepythonplugin)
+target_compile_definitions(katepythonplugin PRIVATE TRANSLATION_DOMAIN="katepythonplugin")
+
+target_link_libraries(
+  katepythonplugin
+  PRIVATE
+    KF5::I18n
+    KF5::TextEditor
+)
+
+target_sources(
+  katepythonplugin
+  PRIVATE
+    katepythonplugin.cpp
+    plugin.qrc
+)

addons/python/Messages.sh

+#! /bin/sh
+$XGETTEXT *.cpp -o $podir/katecloseexceptplugin.pot

addons/python/katepythonplugin.cpp

+/*
+ *
+ *  SPDX-FileCopyrightText: 2022 Christoph Cullmann <cullmann@kde.org>
+ *
+ *  SPDX-License-Identifier: LGPL-2.0-or-later
+ */
+
+#include "katepythonplugin.h"
+
+#include <KPluginFactory>
+
+K_PLUGIN_FACTORY_WITH_JSON(KatePythonPluginFactory, "katepythonplugin.json", registerPlugin<KatePythonPlugin>();)
+
+KatePythonPlugin::KatePythonPlugin(QObject *application, const QList<QVariant> &)
+    : KTextEditor::Plugin(application)
+{
+}
+
+QObject *KatePythonPlugin::createView(KTextEditor::MainWindow *)
+{
+    return nullptr;
+}
+
+#include "katepythonplugin.moc"

addons/python/katepythonplugin.h

+/*
+ *
+ *  SPDX-FileCopyrightText: 2022 Christoph Cullmann <cullmann@kde.org>
+ *
+ *  SPDX-License-Identifier: LGPL-2.0-or-later
+ */
+
+#ifndef KATE_PYTHON_PLUGIN
+#define KATE_PYTHON_PLUGIN
+
+#include <QVariant>
+
+#include <KTextEditor/Plugin>
+
+class KatePythonPlugin : public KTextEditor::Plugin
+{
+    Q_OBJECT
+public:
+    KatePythonPlugin(QObject * = nullptr, const QList<QVariant> & = QList<QVariant>());
+    ~KatePythonPlugin() = default;
+    QObject *createView(KTextEditor::MainWindow *) override;
+};
+
+#endif // __SRC__CLOSE_EXCEPT_PLUGIN_H__

addons/python/katepythonplugin.json

+{
+    "KPlugin": {
+        "Description": "Plugin that allows Python scripting for Kate",
+        "Name": "Python Scripting",
+        "ServiceTypes": [
+            "KTextEditor/Plugin"
+        ]
+    }
+}

addons/python/plugin.qrc

+<!DOCTYPE RCC>
+<RCC version="1.0">
+    <qresource prefix="/kxmlgui5/katecloseexceptplugin">
+        <file>ui.rc</file>
+    </qresource>
+</RCC>

addons/python/ui.rc

+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE gui SYSTEM "kpartgui.dtd">
+<gui name="katecloseexcept" library="katecloseexceptplugin" version="4" translationDomain="katecloseexceptplugin">
+  <MenuBar>
+    <Menu name="file">
+      <text>&amp;File</text>
+      <Action name="file_close_except" group="close_merge"/>
+      <Action name="file_close_like" group="close_merge"/>
+    </Menu>
+  </MenuBar>
+</gui>
+<!-- kate: space-indent on; indent-width 4; replace-tabs on; -->