Address some clang-tidy warnings

src/script/cpp_api/s_mainmenu.cpp

@@ -21,7 +21,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "cpp_api/s_internal.h"
 #include "common/c_converter.h"
 
-void ScriptApiMainMenu::setMainMenuData(MainMenuDataForScript *data)
+void ScriptApiMainMenu::setMainMenuData(const MainMenuDataForScript *data)
 {
 	SCRIPTAPI_PRECHECKHEADER
 
@@ -38,7 +38,7 @@ void ScriptApiMainMenu::setMainMenuData(MainMenuDataForScript *data)
 	lua_pop(L, 1);
 }
 
-void ScriptApiMainMenu::handleMainMenuEvent(std::string text)
+void ScriptApiMainMenu::handleMainMenuEvent(const std::string &text)
 {
 	SCRIPTAPI_PRECHECKHEADER
 

src/script/cpp_api/s_mainmenu.h

@@ -29,13 +29,13 @@ public:
 	 * Hand over MainMenuDataForScript to lua to inform lua of the content
 	 * @param data the data
 	 */
-	void setMainMenuData(MainMenuDataForScript *data);
+	void setMainMenuData(const MainMenuDataForScript *data);
 
 	/**
 	 * process events received from formspec
 	 * @param text events in textual form
 	 */
-	void handleMainMenuEvent(std::string text);
+	void handleMainMenuEvent(const std::string &text);
 
 	/**
 	 * process field data received from formspec

src/script/lua_api/l_item.cpp

@@ -678,7 +678,7 @@ int ModApiItem::l_get_content_id(lua_State *L)
 
 	// If this is called at mod load time, NodeDefManager isn't aware of
 	// aliases yet, so we need to handle them manually
-	std::string alias_name = idef->getAlias(name);
+	const auto &alias_name = idef->getAlias(name);
 
 	content_t content_id;
 	if (alias_name != name) {

src/script/lua_api/l_mainmenu.cpp

@@ -43,7 +43,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "common/c_converter.h"
 
 /******************************************************************************/
-std::string ModApiMainMenu::getTextData(lua_State *L, std::string name)
+std::string ModApiMainMenu::getTextData(lua_State *L, const std::string &name)
 {
 	lua_getglobal(L, "gamedata");
 
@@ -56,7 +56,7 @@ std::string ModApiMainMenu::getTextData(lua_State *L, std::string name)
 }
 
 /******************************************************************************/
-int ModApiMainMenu::getIntegerData(lua_State *L, std::string name,bool& valid)
+int ModApiMainMenu::getIntegerData(lua_State *L, const std::string &name, bool& valid)
 {
 	lua_getglobal(L, "gamedata");
 
@@ -65,14 +65,14 @@ int ModApiMainMenu::getIntegerData(lua_State *L, std::string name,bool& valid)
 	if(lua_isnil(L, -1)) {
 		valid = false;
 		return -1;
-		}
+	}
 
 	valid = true;
 	return luaL_checkinteger(L, -1);
 }
 
 /******************************************************************************/
-int ModApiMainMenu::getBoolData(lua_State *L, std::string name,bool& valid)
+int ModApiMainMenu::getBoolData(lua_State *L, const std::string &name, bool& valid)
 {
 	lua_getglobal(L, "gamedata");
 
@@ -81,7 +81,7 @@ int ModApiMainMenu::getBoolData(lua_State *L, std::string name,bool& valid)
 	if(lua_isnil(L, -1)) {
 		valid = false;
 		return false;
-		}
+	}
 
 	valid = true;
 	return readParam<bool>(L, -1);
@@ -553,7 +553,7 @@ int ModApiMainMenu::l_create_world(lua_State *L)
 	// Set the settings for world creation
 	// this is a bad hack but the best we have right now..
 	StringMap backup;
-	for (auto it : use_settings) {
+	for (auto &it : use_settings) {
 		if (g_settings->existsLocal(it.first))
 			backup[it.first] = g_settings->get(it.first);
 		g_settings->set(it.first, it.second);
@@ -569,7 +569,7 @@ int ModApiMainMenu::l_create_world(lua_State *L)
 	}
 
 	// Restore previous settings
-	for (auto it : use_settings) {
+	for (auto &it : use_settings) {
 		auto it2 = backup.find(it.first);
 		if (it2 == backup.end())
 			g_settings->remove(it.first); // wasn't set before

src/script/lua_api/l_mainmenu.h

@@ -34,7 +34,7 @@ private:
 	 * @param name name of variable to read
 	 * @return string value of requested variable
 	 */
-	static std::string getTextData(lua_State *L, std::string name);
+	static std::string getTextData(lua_State *L, const std::string &name);
 
 	/**
 	 * read an integer variable from gamedata table within lua stack
@@ -42,7 +42,7 @@ private:
 	 * @param name name of variable to read
 	 * @return integer value of requested variable
 	 */
-	static int getIntegerData(lua_State *L, std::string name,bool& valid);
+	static int getIntegerData(lua_State *L, const std::string &name, bool& valid);
 
 	/**
 	 * read a bool variable from gamedata table within lua stack
@@ -50,7 +50,7 @@ private:
 	 * @param name name of variable to read
 	 * @return bool value of requested variable
 	 */
-	static int getBoolData(lua_State *L, std::string name,bool& valid);
+	static int getBoolData(lua_State *L, const std::string &name ,bool& valid);
 
 	/**
 	 * Checks if a path may be modified. Paths in the temp directory or the user