Lua: Macro support

Allows users to use "%{Lua: ...}" to execute Lua code in their macros.
Adds "Macro" module with expand() and value() functions.

Change-Id: I6315b0646fbb503a77fd0cc631aed204abf3b699
Reviewed-by: Cristian Adam <cristian.adam@qt.io>

src/plugins/lua/CMakeLists.txt

@@ -13,6 +13,7 @@ add_qtc_plugin(Lua
     bindings/install.cpp
     bindings/json.cpp
     bindings/localsocket.cpp
+    bindings/macro.cpp
     bindings/messagemanager.cpp
     bindings/qtcprocess.cpp
     bindings/settings.cpp
@@ -21,6 +22,7 @@ add_qtc_plugin(Lua
     bindings/utils.cpp
     luaengine.cpp
     luaengine.h
+    luaexpander.cpp
     luaplugin.cpp
     luapluginspec.cpp
     luapluginspec.h

src/plugins/lua/bindings/macro.cpp

@@ -0,0 +1,26 @@
+// 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 <utils/macroexpander.h>
+
+namespace Lua::Internal {
+
+void setupMacroModule()
+{
+    registerProvider("Macro", [](sol::state_view lua) {
+        sol::table module = lua.create_table();
+
+        module.set_function("expand", [](const QString &s) -> QString {
+            return Utils::globalMacroExpander()->expand(s);
+        });
+
+        module.set_function("value", [](const QString &s) -> QString {
+            return Utils::globalMacroExpander()->value(s.toUtf8());
+        });
+
+        return module;
+    });
+}
+} // namespace Lua::Internal

src/plugins/lua/lua.qbs

@@ -20,6 +20,7 @@ QtcPlugin {
         "lua_global.h",
         "luaengine.cpp",
         "luaengine.h",
+        "luaexpander.cpp",
         "luaplugin.cpp",
         "luapluginspec.cpp",
         "luapluginspec.h",
@@ -45,6 +46,7 @@ QtcPlugin {
             "install.cpp",
             "json.cpp",
             "localsocket.cpp",
+            "macro.cpp",
             "messagemanager.cpp",
             "qtcprocess.cpp",
             "settings.cpp",

src/plugins/lua/luaengine.cpp

@@ -54,13 +54,10 @@ public:
     sol::state lua;
 };
 
-// Runs the gives script in a new Lua state. The returned Object manages the lifetime of the state.
-std::unique_ptr<Utils::LuaState> runScript(
-    const QString &script, const QString &name, std::function<void(sol::state &)> customizeState)
+void prepareLuaState(
+    sol::state &lua, const QString &name, const std::function<void(sol::state &)> &customizeState)
 {
-    std::unique_ptr<LuaStateImpl> opaque = std::make_unique<LuaStateImpl>();
-
-    opaque->lua.open_libraries(
+    lua.open_libraries(
         sol::lib::base,
         sol::lib::bit32,
         sol::lib::coroutine,
@@ -73,7 +70,7 @@ std::unique_ptr<Utils::LuaState> runScript(
         sol::lib::table,
         sol::lib::utf8);
 
-    opaque->lua["print"] = [prefix = name, printToOutputPane = true](sol::variadic_args va) {
+    lua["print"] = [prefix = name, printToOutputPane = true](sol::variadic_args va) {
         const QString msg = variadicToStringList(va).join("\t");
 
         qDebug().noquote() << "[" << prefix << "]" << msg;
@@ -84,23 +81,33 @@ std::unique_ptr<Utils::LuaState> runScript(
         }
     };
 
-    opaque->lua.new_usertype<ScriptPluginSpec>(
+    lua.new_usertype<ScriptPluginSpec>(
         "PluginSpec", sol::no_constructor, "name", sol::property([](ScriptPluginSpec &self) {
             return self.name;
         }));
 
-    opaque->lua["PluginSpec"] = ScriptPluginSpec{name, {}, std::make_unique<QObject>()};
+    lua["PluginSpec"] = ScriptPluginSpec{name, {}, std::make_unique<QObject>()};
 
     for (const auto &[name, func] : d->m_providers.asKeyValueRange()) {
-        opaque->lua["package"]["preload"][name.toStdString()] =
-            [func = func](const sol::this_state &s) { return func(s); };
+        lua["package"]["preload"][name.toStdString()] = [func = func](const sol::this_state &s) {
+            return func(s);
+        };
     }
 
     for (const auto &func : d->m_autoProviders)
-        func(opaque->lua);
+        func(lua);
 
     if (customizeState)
-        customizeState(opaque->lua);
+        customizeState(lua);
+}
+
+// Runs the gives script in a new Lua state. The returned Object manages the lifetime of the state.
+std::unique_ptr<Utils::LuaState> runScript(
+    const QString &script, const QString &name, std::function<void(sol::state &)> customizeState)
+{
+    std::unique_ptr<LuaStateImpl> opaque = std::make_unique<LuaStateImpl>();
+
+    prepareLuaState(opaque->lua, name, customizeState);
 
     auto result
         = opaque->lua
@@ -116,6 +123,16 @@ std::unique_ptr<Utils::LuaState> runScript(
     return opaque;
 }
 
+sol::protected_function_result runFunction(
+    sol::state &lua,
+    const QString &script,
+    const QString &name,
+    std::function<void(sol::state &)> customizeState)
+{
+    prepareLuaState(lua, name, customizeState);
+    return lua.safe_script(script.toStdString(), sol::script_pass_on_error, name.toStdString());
+}
+
 void registerProvider(const QString &packageName, const PackageProvider &provider)
 {
     QTC_ASSERT(!d->m_providers.contains(packageName), return);

src/plugins/lua/luaengine.h

@@ -101,6 +101,12 @@ LUA_EXPORT std::unique_ptr<Utils::LuaState> runScript(
     const QString &name,
     std::function<void(sol::state &)> customizeState = {});
 
+sol::protected_function_result runFunction(
+    sol::state &lua,
+    const QString &script,
+    const QString &name,
+    std::function<void(sol::state &)> customizeState = {});
+
 void setupLuaEngine(QObject *guard);
 
 } // namespace Lua

src/plugins/lua/luaexpander.cpp

@@ -0,0 +1,104 @@
+// 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 "luatr.h"
+
+#include <utils/macroexpander.h>
+
+using namespace Utils;
+
+namespace Lua::Internal {
+
+void setNext(
+    MacroExpander *expander,
+    sol::state &lua,
+    auto &table,
+    const QByteArray &key,
+    QList<QByteArray>::const_iterator it,
+    QList<QByteArray>::const_iterator end)
+{
+    if (it + 1 == end) {
+        if (expander->isPrefixVariable(key)) {
+            table.set_function(it->toStdString(), [key, expander](const QString &s) -> QString {
+                return expander->value(key + s.toUtf8());
+            });
+        } else {
+            table.set(it->toStdString(), expander->value(key));
+        }
+    } else {
+        auto existingTable = table.template get<sol::optional<sol::table>>(it->toStdString());
+        if (existingTable) {
+            setNext(expander, lua, *existingTable, key, it + 1, end);
+        } else {
+            sol::table newTable = lua.create_table();
+            setNext(expander, lua, newTable, key, it + 1, end);
+            table.set(it->toStdString(), newTable);
+        }
+    }
+};
+
+sol::protected_function_result run(sol::state &lua, QString statement, MacroExpander *expander)
+{
+    return runFunction(lua, statement, "Statement", [expander](sol::state &lua) {
+        sol::global_table &t = lua.globals();
+
+        for (QByteArray key : expander->visibleVariables()) {
+            if (key != "Lua:<value>") {
+                if (key.endsWith(":<value>"))
+                    key = key.chopped(7);
+
+                QList<QByteArray> parts = key.split(':');
+                parts.removeIf([](const QByteArray &part) { return part.isEmpty(); });
+                setNext(expander, lua, t, key, parts.cbegin(), parts.cend());
+            }
+        }
+    });
+}
+
+expected_str<QString> tryRun(const QString statement, MacroExpander *expander)
+{
+    sol::state lua;
+
+    auto result = run(lua, statement, expander);
+    if (!result.valid()) {
+        sol::error err = result;
+        return make_unexpected(QString::fromStdString(err.what()));
+    }
+
+    QStringList results;
+
+    for (int i = 1; i <= result.return_count(); i++) {
+        size_t l;
+        const char *s = luaL_tolstring(result.lua_state(), int(i), &l);
+        results.append(QString::fromUtf8(s, int(l)));
+    }
+    return results.join(QLatin1Char(' '));
+}
+
+void setupLuaExpander(MacroExpander *expander)
+{
+    expander->registerPrefix(
+        "Lua",
+        Tr::tr("Evaluate simple Lua statements.<br>"
+               "Literal '}' characters must be escaped as \"\\}\", "
+               "'\\' characters must be escaped as \"\\\\\", "
+               "'#' characters must be escaped as \"\\#\", "
+               "and \"%{\" must be escaped as \"%\\{\"."),
+        [expander](const QString &statement) -> QString {
+            if (statement.isEmpty())
+                return Tr::tr("No Lua statement to evaluate.");
+
+            expected_str<QString> result = tryRun("return " + statement, expander);
+            if (result)
+                return *result;
+
+            result = tryRun(statement, expander);
+            if (!result)
+                return result.error();
+
+            return *result;
+        });
+}
+
+} // namespace Lua::Internal

src/plugins/lua/luaplugin.cpp

@@ -15,6 +15,7 @@
 
 #include <utils/algorithm.h>
 #include <utils/layoutbuilder.h>
+#include <utils/macroexpander.h>
 #include <utils/qtcprocess.h>
 #include <utils/theme/theme.h>
 
@@ -41,6 +42,7 @@ void setupHookModule();
 void setupInstallModule();
 void setupJsonModule();
 void setupLocalSocketModule();
+void setupMacroModule();
 void setupMessageManagerModule();
 void setupProcessModule();
 void setupQtModule();
@@ -49,6 +51,8 @@ void setupTextEditorModule();
 void setupTranslateModule();
 void setupUtilsModule();
 
+void setupLuaExpander(MacroExpander *expander);
+
 class LuaJsExtension : public QObject
 {
     Q_OBJECT
@@ -256,6 +260,7 @@ public:
         setupInstallModule();
         setupJsonModule();
         setupLocalSocketModule();
+        setupMacroModule();
         setupMessageManagerModule();
         setupProcessModule();
         setupQtModule();
@@ -266,6 +271,8 @@ public:
 
         Core::JsExpander::registerGlobalObject("Lua", [] { return new LuaJsExtension(); });
 
+        setupLuaExpander(globalMacroExpander());
+
         pluginSpecsFromArchiveFactories().push_back([](const FilePath &path) {
             QList<PluginSpec *> plugins;
             auto dirs = path.dirEntries(QDir::Dirs | QDir::NoDotAndDotDot);

src/plugins/lua/meta/macro.lua

@@ -0,0 +1,14 @@
+-- Copyright (C) 2024 The Qt Company Ltd.
+-- SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only WITH Qt-GPL-exception-1.0
+
+---@meta Macro
+
+local macro = {}
+
+---Returns globalExpander():value(variableName).
+function macro.value(variableName) end
+
+---Returns globalExpander():expand(stringWithVariables).
+function macro.expand(stringWithVariables) end
+
+return macro