README.md, OptionalNullPtr<>, potential ub in samples

Author: uralm1

README.md

@@ -37,7 +37,7 @@ int main() {
         bot.getApi().sendMessage(message->chat->id, "Your message is: " + message->text);
     });
     try {
-        printf("Bot username: %s\n", bot.getApi().getMe()->username.c_str());
+        printf("Bot name: %s\n", bot.getApi().getMe()->firstName.c_str());
         TgBot::TgLongPoll longPoll(bot);
         while (true) {
             printf("Long poll started\n");

include/tgbot/Optional.h

@@ -5,16 +5,16 @@
 
 namespace TgBot {
 
+// Optional via boost::optional
 template<typename T>
-  using Optional = boost::optional<T>;
+    using Optional = boost::optional<T>;
 
-// use for: OptionalPtr<std::shared/unique_ptr<TYPE>>
-// for pointers, we assume optional value == nullptr (or not owned, etc)
+// Optional is nullptr (for std::shared/unique_ptr<> etc)
 template<typename T>
-  using OptionalPtr = T;
+    using OptionalNullPtr = T;
 
 template<typename T>
-  using Required = T;
+    using Required = T;
 
 }
 

include/tgbot/TgTypeParser.h

@@ -899,19 +899,15 @@ class TGBOT_API TgTypeParser {
 
 private:
     inline void removeLastComma(std::string& input) const {
-        if (!input.empty() && input.back() == ',') input.erase(input.length() - 1);
+        if (!input.empty() && input.back() == ',') input.pop_back();
     }
 
     template<typename T>
     inline void appendToJson(std::string& json, const std::string& varName, const Optional<T>& value) const {
         if (!value) {
             return;
         }
-        json += '"';
-        json += varName;
-        json += R"(":)";
-        json += *value;
-        json += ',';
+        appendToJson(json, varName, *value);
     }
 
     template<typename T>

include/tgbot/types/InlineKeyboardButton.h

@@ -47,14 +47,14 @@ class InlineKeyboardButton {
      * The Web App will be able to send an arbitrary message on behalf of the user using the method Api::answerWebAppQuery.
      * Available only in private chats between a user and the bot.
      */
-    OptionalPtr<WebAppInfo::Ptr> webApp;
+    OptionalNullPtr<WebAppInfo::Ptr> webApp;
 
     /**
      * @brief Optional. An HTTPS URL used to automatically authorize the user.
      *
      * Can be used as a replacement for the [Telegram Login Widget](https://core.telegram.org/widgets/login).
      */
-    OptionalPtr<LoginUrl::Ptr> loginUrl;
+    OptionalNullPtr<LoginUrl::Ptr> loginUrl;
 
     /**
      * @brief Optional. If set, pressing the button will prompt the user to select one of their chats, open that chat and insert the bot's username and the specified inline query in the input field.
@@ -74,14 +74,14 @@ class InlineKeyboardButton {
     /**
      * @brief Optional. If set, pressing the button will prompt the user to select one of their chats of the specified type, open that chat and insert the bot's username and the specified inline query in the input field
      */
-    OptionalPtr<SwitchInlineQueryChosenChat::Ptr> switchInlineQueryChosenChat;
+    OptionalNullPtr<SwitchInlineQueryChosenChat::Ptr> switchInlineQueryChosenChat;
 
     /**
      * @brief Optional. Description of the game that will be launched when the user presses the button.
      *
      * NOTE: This type of button must always be the first button in the first row.
      */
-    OptionalPtr<CallbackGame::Ptr> callbackGame;
+    OptionalNullPtr<CallbackGame::Ptr> callbackGame;
 
     /**
      * @brief Optional. Specify True, to send a [Pay button](https://core.telegram.org/bots/api#payments).

include/tgbot/types/MessageEntity.h

@@ -55,7 +55,7 @@ class MessageEntity {
     /**
      * @brief Optional. For Type::TextMention only, the mentioned user
      */
-    OptionalPtr<User::Ptr> user;
+    OptionalNullPtr<User::Ptr> user;
 
     /**
      * @brief Optional. For Type::Pre only, the programming language of the entity text

samples/echobot-curl-client/src/main.cpp

@@ -33,7 +33,7 @@ int main() {
     });
 
     try {
-        printf("Bot username: %s\n", bot.getApi().getMe()->username->c_str());
+        printf("Bot name: %s\n", bot.getApi().getMe()->firstName.c_str());
         bot.getApi().deleteWebhook();
 
         TgLongPoll longPoll(bot);

samples/echobot-setmycommands/src/main.cpp

@@ -59,7 +59,7 @@ int main() {
     });
 
     try {
-        printf("Bot username: %s\n", bot.getApi().getMe()->username->c_str());
+        printf("Bot name: %s\n", bot.getApi().getMe()->firstName.c_str());
         bot.getApi().deleteWebhook();
 
         TgLongPoll longPoll(bot);

samples/echobot-submodule/src/main.cpp

@@ -31,7 +31,7 @@ int main() {
     });
 
     try {
-        printf("Bot username: %s\n", bot.getApi().getMe()->username->c_str());
+        printf("Bot name: %s\n", bot.getApi().getMe()->firstName.c_str());
         bot.getApi().deleteWebhook();
 
         TgLongPoll longPoll(bot);

samples/echobot-webhook-server/src/main.cpp

@@ -33,7 +33,7 @@ int main() {
     });
 
     try {
-        printf("Bot username: %s\n", bot.getApi().getMe()->username->c_str());
+        printf("Bot name: %s\n", bot.getApi().getMe()->firstName.c_str());
 
         TgWebhookTcpServer webhookServer(8080, bot);
 

samples/echobot/src/main.cpp

@@ -31,7 +31,10 @@ int main() {
     });
 
     try {
-        printf("Bot username: %s\n", bot.getApi().getMe()->username.value_or(string{"unknown"}).c_str());
+        auto user = bot.getApi().getMe();
+        printf("Bot name: %s, username: %s\n",
+            user->firstName.c_str(),
+            user->username.value_or(string{"unknown"}).c_str());
         bot.getApi().deleteWebhook();
 
         TgLongPoll longPoll(bot);