Lua: Add support for translation

Change-Id: I5398480233c830bb08c641bc8193b068fb037032
Reviewed-by: Eike Ziller <eike.ziller@qt.io>

share/qtcreator/CMakeLists.txt

@@ -5,6 +5,7 @@ set(resource_directories
   indexer_preincludes
   jsonschemas
   lua-plugins
+  lua-lupdate
   modeleditor
   qmldesigner
   qmlicons

share/qtcreator/lua-lupdate/README.md

@@ -0,0 +1,65 @@
+# lupdate.lua
+
+lupdate.lua allows you to update your .ts files from your .lua files.
+
+## Installation
+
+You need to install lua, luarocks and luafilesystem.
+
+On macOS:
+
+```sh
+$ brew install lua luarocks
+$ luarocks install luafilesystem
+```
+
+For other platforms see: [Download luarocks](https://github.com/luarocks/luarocks/wiki/Download)
+
+## Usage
+
+You need to add a "languages" key to your plugin spec file.
+
+```lua
+--- In your plugin.lua file
+return {
+    Name = "MyPlugin",
+    Version = "1.0.0",
+    languages = {"de", "fr", "en"},
+    --- ....
+} --[[@as QtcPlugin]]
+```
+
+Then run the lupdate.lua script in your plugin directory. Make sure that lupdate is in your PATH.
+
+```sh
+$ # export PATH=$PATH:/path/to/Qt/bin
+$ cd my-plugin
+$ lua lupdate.lua
+```
+
+Once you have the .ts files you can use Qt Linguist to translate your strings.
+
+After translation you can run lrelease to generate the .qm files.
+
+```sh
+$ cd ts
+$ lrelease *.ts
+```
+
+## Background
+
+Since Qt's lupdate does not currently support lua files, the lupdate.lua script uses a trick
+to make it work. It creates a temporary file for each lua file and adds a comment at the start
+and end of the file:
+
+```lua
+--- class Plugin { Q_OBJECT
+
+print(tr("Hello World"))
+
+--- }
+```
+
+That way lupdate thinks its inside a C++ Plugin and takes as context the name of the class, in this case "Plugin".
+
+It then starts the actual lupdate tool to update the .ts files.

share/qtcreator/lua-lupdate/lupdate.lua

@@ -0,0 +1,99 @@
+--- luarocks install luafilesystem
+local lfs = require "lfs"
+
+function string:endswith(suffix)
+    return self:sub(- #suffix) == suffix
+end
+
+function findLUpdate()
+    if os.execute("lupdate -version 2>/dev/null") then
+        return "lupdate"
+    end
+    QtDir = os.getenv("QTDIR")
+    if QtDir then
+        local path = QtDir .. "/bin/lupdate"
+        if os.execute(path .. " -version 2>/dev/null") then
+            return path
+        end
+    end
+    return "lupdate"
+end
+
+LUpdatePath = findLUpdate()
+TmpFiles = {}
+
+
+local curdir, err = lfs.currentdir()
+if not curdir then
+    print("Error: " .. err)
+    return
+end
+
+local folderName = curdir:match("([^/]+)$")
+print("Working on: " .. curdir)
+local pluginSpecName = folderName .. ".lua"
+
+--- Noop tr function
+function tr(str) return str end
+
+local specScript, err = loadfile(curdir .. "/" .. pluginSpecName)
+if not specScript then
+    print("Error: " .. err)
+    return
+end
+
+local spec, err = specScript()
+
+if not spec then
+    print("Error: " .. err)
+    return
+end
+
+if not spec.languages then
+    print("Error: No languages specified in plugin spec.")
+    return
+end
+
+TrContext = spec.Name:gsub("[^a-zA-Z]", "_")
+
+for file in lfs.dir(".") do
+    if file ~= "." and file ~= ".." and file:endswith(".lua") and file ~= "lupdate.lua" then
+        local f = io.open(file, "r")
+        if f then
+            local contents = f:read("a")
+            local tmpname = os.tmpname()
+            local tf = io.open(tmpname, "w")
+            if tf then
+                tf:write("--- class " .. TrContext .. " { Q_OBJECT \n")
+                tf:write(contents)
+                tf:write("--- }\n")
+                tf:close()
+                table.insert(TmpFiles, tmpname)
+            end
+        end
+    end
+end
+
+AllFiles = table.concat(TmpFiles, "\n")
+LstFileName = os.tmpname()
+local lstFile = io.open(LstFileName, "w")
+
+if lstFile then
+    lstFile:write(AllFiles)
+    lstFile:close()
+
+    local allLangs = ""
+    for _, lang in ipairs(spec.languages) do
+        local name = "ts/" .. string.lower(folderName) .. "_" .. lang .. ".ts"
+        allLangs = allLangs .. name .. " "
+    end
+
+    lfs.mkdir("ts")
+    os.execute(LUpdatePath .. " @" .. LstFileName .. " -ts " .. allLangs)
+
+    --- Cleanup
+    os.remove(LstFileName)
+    for _, file in ipairs(TmpFiles) do
+        os.remove(file)
+    end
+end

src/plugins/lua/CMakeLists.txt

@@ -17,6 +17,7 @@ add_qtc_plugin(Lua
     bindings/qtcprocess.cpp
     bindings/settings.cpp
     bindings/texteditor.cpp
+    bindings/translate.cpp
     bindings/utils.cpp
     luaengine.cpp
     luaengine.h

src/plugins/lua/bindings/translate.cpp

@@ -0,0 +1,23 @@
+// Copyright (C) 2024 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only WITH Qt-GPL-exception-1.0
+
+#include "../luaengine.h"
+
+#include <QCoreApplication>
+
+namespace Lua::Internal {
+
+void addTranslateModule()
+{
+    ::Lua::LuaEngine::autoRegister([](sol::state_view lua) {
+        const ScriptPluginSpec *pluginSpec = lua.get<ScriptPluginSpec *>("PluginSpec");
+        const QString trContext
+            = QString(pluginSpec->name).replace(QRegularExpression("[^a-zA-Z]"), "_");
+
+        lua["tr"] = [trContext](const char *text) -> QString {
+            return QCoreApplication::translate(trContext.toUtf8().constData(), text);
+        };
+    });
+}
+
+} // namespace Lua::Internal

src/plugins/lua/luaengine.cpp

@@ -192,8 +192,9 @@ expected_str<LuaPluginSpec *> LuaEngine::loadPlugin(const Utils::FilePath &path)
         return make_unexpected(contents.error());
 
     sol::state lua;
+    lua["tr"] = [](const QString &str) { return str; };
 
-    auto result = lua.safe_script(
+    sol::protected_function_result result = lua.safe_script(
         std::string_view(contents->data(), contents->size()),
         sol::script_pass_on_error,
         path.fileName().toUtf8().constData());

src/plugins/lua/luaplugin.cpp

@@ -46,6 +46,7 @@ void addProcessModule();
 void addQtModule();
 void addSettingsModule();
 void addTextEditorModule();
+void addTranslateModule();
 void addUtilsModule();
 
 class LuaJsExtension : public QObject
@@ -262,6 +263,7 @@ public:
         addQtModule();
         addSettingsModule();
         addTextEditorModule();
+        addTranslateModule();
         addUtilsModule();
 
         Core::JsExpander::registerGlobalObject("Lua", [] { return new LuaJsExtension(); });

src/plugins/lua/luapluginspec.cpp

@@ -6,6 +6,8 @@
 #include "luaengine.h"
 #include "luatr.h"
 
+#include <coreplugin/icore.h>
+
 #include <extensionsystem/extensionsystemtr.h>
 
 #include <utils/algorithm.h>
@@ -14,6 +16,7 @@
 
 #include <QJsonDocument>
 #include <QLoggingCategory>
+#include <QTranslator>
 
 Q_LOGGING_CATEGORY(luaPluginSpecLog, "qtc.lua.pluginspec", QtWarningMsg)
 
@@ -45,6 +48,7 @@ LuaPluginSpec::LuaPluginSpec()
 
 expected_str<LuaPluginSpec *> LuaPluginSpec::create(const FilePath &filePath, sol::table pluginTable)
 {
+    const FilePath directory = filePath.parentDir();
     std::unique_ptr<LuaPluginSpec> pluginSpec(new LuaPluginSpec());
 
     if (!pluginTable.get_or<sol::function>("setup", {}))
@@ -63,8 +67,20 @@ expected_str<LuaPluginSpec *> LuaPluginSpec::create(const FilePath &filePath, so
     if (!r)
         return make_unexpected(r.error());
 
+    const QString langId = Core::ICore::userInterfaceLanguage();
+    FilePath path = directory / "ts" / QString("%1_%2.qm").arg(directory.fileName()).arg(langId);
+
+    QTranslator *translator = new QTranslator(qApp);
+    bool success = translator->load(path.toFSPathString(), directory.toFSPathString());
+    if (success)
+        qApp->installTranslator(translator);
+    else {
+        delete translator;
+        qCInfo(luaPluginSpecLog) << "No translation found";
+    }
+
     pluginSpec->setFilePath(filePath);
-    pluginSpec->setLocation(filePath.parentDir());
+    pluginSpec->setLocation(directory);
 
     pluginSpec->d->pluginScriptPath = filePath;
     pluginSpec->d->printToOutputPane = pluginTable.get_or("printToOutputPane", false);

src/plugins/lua/meta/qtc.lua

@@ -1,5 +1,9 @@
 ---@meta
 
+---@class PluginSpec
+---@field name string The name of the plugin.
+---@field pluginDirectory FilePath The directory of the plugin.
+PluginSpec = {}
 ---The global qtc object defined in the Lua plugin.
 ---@class qtc
 Qtc = {}
@@ -24,6 +28,7 @@ Qtc = {}
 ---@field Mimetypes? string XML MIME-info for registering additional or adapting built-in MIME types.
 ---@field JsonWizardPaths? string[] A list of paths relative to the plugin location or paths to the Qt resource system that are searched for template-based wizards.
 ---@field printToOutputPane? boolean Whether the `print(...)` function should print to the output pane or not. ( Default: false )
+---@field languages? string[] A list of languages that the plugin supports.
 QtcPlugin = {}
 
 ---@class QtcPluginDependency