Add OptionParser::add_check.

GitOrigin-RevId: dbf50403ba264ddf04b50197f0b54500c8f761ce

td/telegram/cli.cpp

@@ -4356,6 +4356,12 @@ void main(int argc, char **argv) {
                      [&](Slice parameter) { api_id = to_integer<int32>(parameter); });
   options.add_option('\0', "api-hash", "Set Telegram API hash", [&](Slice parameter) { api_hash = parameter.str(); });
   options.add_option('\0', "api_hash", "Set Telegram API hash", [&](Slice parameter) { api_hash = parameter.str(); });
+  options.add_check([&] {
+    if (api_id == 0 || api_hash.empty()) {
+      return Status::Error("You must provide valid api-id and api-hash obtained at https://my.telegram.org");
+    }
+    return Status::OK();
+  });
   auto res = options.run(argc, argv);
   if (res.is_error()) {
     LOG(PLAIN) << "tg_cli: " << res.error().message();
@@ -4369,13 +4375,6 @@ void main(int argc, char **argv) {
     return;
   }
 
-  if (api_id == 0 || api_hash.empty()) {
-    LOG(PLAIN) << "tg_cli: "
-               << "You should provide some valid api_id and api_hash";
-    LOG(PLAIN) << options;
-    return;
-  }
-
   SET_VERBOSITY_LEVEL(new_verbosity_level);
 
   {

tdutils/td/utils/OptionParser.cpp

@@ -47,6 +47,10 @@ void OptionParser::add_option(char short_key, Slice long_key, Slice description,
   });
 }
 
+void OptionParser::add_check(std::function<Status()> check) {
+  checks_.push_back(std::move(check));
+}
+
 Result<vector<char *>> OptionParser::run(int argc, char *argv[]) {
   std::unordered_map<char, const Option *> short_options;
   std::unordered_map<string, const Option *> long_options;
@@ -143,6 +147,9 @@ Result<vector<char *>> OptionParser::run(int argc, char *argv[]) {
       TRY_STATUS(option->arg_callback(parameter));
     }
   }
+  for (auto &check : checks_) {
+    TRY_STATUS(check());
+  }
 
   return std::move(non_options);
 }

tdutils/td/utils/OptionParser.h

@@ -40,6 +40,8 @@ class OptionParser {
 
   void add_option(char short_key, Slice long_key, Slice description, std::function<void(void)> callback);
 
+  void add_check(std::function<Status()> check);
+
   // returns found non-option parameters
   Result<vector<char *>> run(int argc, char *argv[]) TD_WARN_UNUSED_RESULT;
 
@@ -47,6 +49,7 @@ class OptionParser {
 
  private:
   vector<Option> options_;
+  vector<std::function<Status()>> checks_;
   string description_;
 };