Add POT generation feature in Editor

doc/classes/EditorPlugin.xml

@@ -142,6 +142,15 @@
 				Adds a custom submenu under [b]Project > Tools >[/b] [code]name[/code]. [code]submenu[/code] should be an object of class [PopupMenu]. This submenu should be cleaned up using [code]remove_tool_menu_item(name)[/code].
 			</description>
 		</method>
+		<method name="add_translation_parser_plugin">
+			<return type="void">
+			</return>
+			<argument index="0" name="parser" type="EditorTranslationParserPlugin">
+			</argument>
+			<description>
+				Registers a custom translation parser plugin for extracting translatable strings from custom files.
+			</description>
+		</method>
 		<method name="apply_changes" qualifiers="virtual">
 			<return type="void">
 			</return>
@@ -464,6 +473,15 @@
 				Removes a menu [code]name[/code] from [b]Project &gt; Tools[/b].
 			</description>
 		</method>
+		<method name="remove_translation_parser_plugin">
+			<return type="void">
+			</return>
+			<argument index="0" name="parser" type="EditorTranslationParserPlugin">
+			</argument>
+			<description>
+				Removes a registered custom translation parser plugin.
+			</description>
+		</method>
 		<method name="save_external_data" qualifiers="virtual">
 			<return type="void">
 			</return>

doc/classes/EditorTranslationParserPlugin.xml

@@ -0,0 +1,48 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<class name="EditorTranslationParserPlugin" inherits="Reference" version="4.0">
+	<brief_description>
+		Plugin for adding custom parsers to extract strings that are to be translated from custom files (.csv, .json etc.).
+	</brief_description>
+	<description>
+		Plugins are registered via [method EditorPlugin.add_translation_parser_plugin] method. To define the parsing and string extraction logic, override the [method parse_text] method in script.
+		The extracted strings will be written into a POT file selected by user under "POT Generation" in "Localization" tab in "Project Settings" menu.
+		Below shows an example of a custom parser that extracts strings in a CSV file to write into a POT.
+		[codeblock]
+		tool
+		extends EditorTranslationParserPlugin
+
+		func parse_text(text, extracted_strings):
+		    var split_strs = text.split(",", false, 0)
+		    for s in split_strs:
+		        extracted_strings.append(s)
+		        #print("Extracted string: " + s)
+
+		func get_recognized_extensions():
+		    return ["csv"]
+		[/codeblock]		
+	</description>
+	<tutorials>
+	</tutorials>
+	<methods>
+		<method name="get_recognized_extensions" qualifiers="virtual">
+			<return type="Array">
+			</return>
+			<description>
+				Gets the list of file extensions to associate with this parser, e.g. [code]["csv"][/code].
+			</description>
+		</method>
+		<method name="parse_text" qualifiers="virtual">
+			<return type="void">
+			</return>
+			<argument index="0" name="text" type="String">
+			</argument>
+			<argument index="1" name="extracted_strings" type="Array">
+			</argument>
+			<description>
+				Override this method to define a custom parsing logic to extract the translatable strings.
+			</description>
+		</method>
+	</methods>
+	<constants>
+	</constants>
+</class>

editor/editor_node.cpp

@@ -85,6 +85,7 @@
 #include "editor/editor_settings.h"
 #include "editor/editor_spin_slider.h"
 #include "editor/editor_themes.h"
+#include "editor/editor_translation_parser.h"
 #include "editor/export_template_manager.h"
 #include "editor/filesystem_dock.h"
 #include "editor/import/editor_import_collada.h"
@@ -138,6 +139,7 @@
 #include "editor/plugins/multimesh_editor_plugin.h"
 #include "editor/plugins/navigation_polygon_editor_plugin.h"
 #include "editor/plugins/node_3d_editor_plugin.h"
+#include "editor/plugins/packed_scene_translation_parser_plugin.h"
 #include "editor/plugins/path_2d_editor_plugin.h"
 #include "editor/plugins/path_3d_editor_plugin.h"
 #include "editor/plugins/physical_bone_3d_editor_plugin.h"
@@ -3589,6 +3591,7 @@ void EditorNode::register_editor_types() {
 	ResourceSaver::set_timestamp_on_save(true);
 
 	ClassDB::register_class<EditorPlugin>();
+	ClassDB::register_class<EditorTranslationParserPlugin>();
 	ClassDB::register_class<EditorImportPlugin>();
 	ClassDB::register_class<EditorScript>();
 	ClassDB::register_class<EditorSelection>();
@@ -6659,6 +6662,10 @@ EditorNode::EditorNode() {
 
 	EditorExport::get_singleton()->add_export_plugin(export_text_to_binary_plugin);
 
+	Ref<PackedSceneEditorTranslationParserPlugin> packed_scene_translation_parser_plugin;
+	packed_scene_translation_parser_plugin.instance();
+	EditorTranslationParser::get_singleton()->add_parser(packed_scene_translation_parser_plugin, EditorTranslationParser::STANDARD);
+
 	_edit_current();
 	current = nullptr;
 	saving_resource = Ref<Resource>();

editor/editor_plugin.cpp

@@ -663,6 +663,14 @@ bool EditorPlugin::get_remove_list(List<Node *> *p_list) {
 void EditorPlugin::restore_global_state() {}
 void EditorPlugin::save_global_state() {}
 
+void EditorPlugin::add_translation_parser_plugin(const Ref<EditorTranslationParserPlugin> &p_parser) {
+	EditorTranslationParser::get_singleton()->add_parser(p_parser, EditorTranslationParser::CUSTOM);
+}
+
+void EditorPlugin::remove_translation_parser_plugin(const Ref<EditorTranslationParserPlugin> &p_parser) {
+	EditorTranslationParser::get_singleton()->remove_parser(p_parser, EditorTranslationParser::CUSTOM);
+}
+
 void EditorPlugin::add_import_plugin(const Ref<EditorImportPlugin> &p_importer) {
 	ResourceFormatImporter::get_singleton()->add_importer(p_importer);
 	EditorFileSystem::get_singleton()->call_deferred("scan");
@@ -796,6 +804,8 @@ void EditorPlugin::_bind_methods() {
 
 	ClassDB::bind_method(D_METHOD("get_undo_redo"), &EditorPlugin::_get_undo_redo);
 	ClassDB::bind_method(D_METHOD("queue_save_layout"), &EditorPlugin::queue_save_layout);
+	ClassDB::bind_method(D_METHOD("add_translation_parser_plugin", "parser"), &EditorPlugin::add_translation_parser_plugin);
+	ClassDB::bind_method(D_METHOD("remove_translation_parser_plugin", "parser"), &EditorPlugin::remove_translation_parser_plugin);
 	ClassDB::bind_method(D_METHOD("add_import_plugin", "importer"), &EditorPlugin::add_import_plugin);
 	ClassDB::bind_method(D_METHOD("remove_import_plugin", "importer"), &EditorPlugin::remove_import_plugin);
 	ClassDB::bind_method(D_METHOD("add_scene_import_plugin", "scene_importer"), &EditorPlugin::add_scene_import_plugin);

editor/editor_plugin.h

@@ -34,6 +34,7 @@
 #include "core/io/config_file.h"
 #include "core/undo_redo.h"
 #include "editor/editor_inspector.h"
+#include "editor/editor_translation_parser.h"
 #include "editor/import/editor_import_plugin.h"
 #include "editor/import/resource_importer_scene.h"
 #include "editor/script_create_dialog.h"
@@ -220,6 +221,9 @@ class EditorPlugin : public Node {
 	virtual void restore_global_state();
 	virtual void save_global_state();
 
+	void add_translation_parser_plugin(const Ref<EditorTranslationParserPlugin> &p_parser);
+	void remove_translation_parser_plugin(const Ref<EditorTranslationParserPlugin> &p_parser);
+
 	void add_import_plugin(const Ref<EditorImportPlugin> &p_importer);
 	void remove_import_plugin(const Ref<EditorImportPlugin> &p_importer);
 

editor/editor_translation_parser.cpp

@@ -0,0 +1,180 @@
+/*************************************************************************/
+/*  editor_translation_parser.cpp                                        */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2020 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2020 Godot Engine contributors (cf. AUTHORS.md).   */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+
+#include "editor_translation_parser.h"
+
+#include "core/error_macros.h"
+#include "core/os/file_access.h"
+#include "core/script_language.h"
+#include "core/set.h"
+
+EditorTranslationParser *EditorTranslationParser::singleton = nullptr;
+
+Error EditorTranslationParserPlugin::parse_file(const String &p_path, Vector<String> *r_extracted_strings) {
+	if (!get_script_instance())
+		return ERR_UNAVAILABLE;
+
+	if (get_script_instance()->has_method("parse_text")) {
+		Error err;
+		FileAccess *file = FileAccess::open(p_path, FileAccess::READ, &err);
+		if (err != OK) {
+			ERR_PRINT("Failed to open " + p_path);
+			return err;
+		}
+		parse_text(file->get_as_utf8_string(), r_extracted_strings);
+		return OK;
+	} else {
+		ERR_PRINT("Custom translation parser plugin's \"func parse_text(text, extracted_strings)\" is undefined.");
+		return ERR_UNAVAILABLE;
+	}
+}
+
+void EditorTranslationParserPlugin::parse_text(const String &p_text, Vector<String> *r_extracted_strings) {
+	if (!get_script_instance())
+		return;
+
+	if (get_script_instance()->has_method("parse_text")) {
+		Array extracted_strings;
+		get_script_instance()->call("parse_text", p_text, extracted_strings);
+		for (int i = 0; i < extracted_strings.size(); i++) {
+			r_extracted_strings->append(extracted_strings[i]);
+		}
+	} else {
+		ERR_PRINT("Custom translation parser plugin's \"func parse_text(text, extracted_strings)\" is undefined.");
+	}
+}
+
+void EditorTranslationParserPlugin::get_recognized_extensions(List<String> *r_extensions) const {
+	if (!get_script_instance())
+		return;
+
+	if (get_script_instance()->has_method("get_recognized_extensions")) {
+		Array extensions = get_script_instance()->call("get_recognized_extensions");
+		for (int i = 0; i < extensions.size(); i++) {
+			r_extensions->push_back(extensions[i]);
+		}
+	} else {
+		ERR_PRINT("Custom translation parser plugin's \"func get_recognized_extensions()\" is undefined.");
+	}
+}
+
+void EditorTranslationParserPlugin::_bind_methods() {
+	ClassDB::add_virtual_method(get_class_static(), MethodInfo(Variant::NIL, "parse_text", PropertyInfo(Variant::STRING, "text"), PropertyInfo(Variant::ARRAY, "extracted_strings")));
+	ClassDB::add_virtual_method(get_class_static(), MethodInfo(Variant::ARRAY, "get_recognized_extensions"));
+}
+
+/////////////////////////
+
+void EditorTranslationParser::get_recognized_extensions(List<String> *r_extensions) const {
+	Set<String> extensions;
+	List<String> temp;
+	for (int i = 0; i < standard_parsers.size(); i++) {
+		standard_parsers[i]->get_recognized_extensions(&temp);
+	}
+	for (int i = 0; i < custom_parsers.size(); i++) {
+		custom_parsers[i]->get_recognized_extensions(&temp);
+	}
+	// Remove duplicates.
+	for (int i = 0; i < temp.size(); i++) {
+		extensions.insert(temp[i]);
+	}
+	for (auto E = extensions.front(); E; E = E->next()) {
+		r_extensions->push_back(E->get());
+	}
+}
+
+bool EditorTranslationParser::can_parse(const String &p_extension) const {
+	List<String> extensions;
+	get_recognized_extensions(&extensions);
+	for (int i = 0; i < extensions.size(); i++) {
+		if (p_extension == extensions[i]) {
+			return true;
+		}
+	}
+	return false;
+}
+
+Ref<EditorTranslationParserPlugin> EditorTranslationParser::get_parser(const String &p_extension) const {
+	// Consider user-defined parsers first.
+	for (int i = 0; i < custom_parsers.size(); i++) {
+		List<String> temp;
+		custom_parsers[i]->get_recognized_extensions(&temp);
+		for (int j = 0; j < temp.size(); j++) {
+			if (temp[j] == p_extension) {
+				return custom_parsers[i];
+			}
+		}
+	}
+
+	for (int i = 0; i < standard_parsers.size(); i++) {
+		List<String> temp;
+		standard_parsers[i]->get_recognized_extensions(&temp);
+		for (int j = 0; j < temp.size(); j++) {
+			if (temp[j] == p_extension) {
+				return standard_parsers[i];
+			}
+		}
+	}
+
+	WARN_PRINT("No translation parser available for \"" + p_extension + "\" extension.");
+
+	return nullptr;
+}
+
+void EditorTranslationParser::add_parser(const Ref<EditorTranslationParserPlugin> &p_parser, ParserType p_type) {
+	if (p_type == ParserType::STANDARD) {
+		standard_parsers.push_back(p_parser);
+	} else if (p_type == ParserType::CUSTOM) {
+		custom_parsers.push_back(p_parser);
+	}
+}
+
+void EditorTranslationParser::remove_parser(const Ref<EditorTranslationParserPlugin> &p_parser, ParserType p_type) {
+	if (p_type == ParserType::STANDARD) {
+		standard_parsers.erase(p_parser);
+	} else if (p_type == ParserType::CUSTOM) {
+		custom_parsers.erase(p_parser);
+	}
+}
+
+EditorTranslationParser *EditorTranslationParser::get_singleton() {
+	if (!singleton) {
+		singleton = memnew(EditorTranslationParser);
+	}
+	return singleton;
+}
+
+EditorTranslationParser::EditorTranslationParser() {
+}
+
+EditorTranslationParser::~EditorTranslationParser() {
+	memdelete(singleton);
+	singleton = nullptr;
+}