Program: 55037
Project: 55037
Buggy source:
@Override public SlackMessageHandle<SlackMessageReply> sendMessage(SlackChannel channel,SlackPreparedMessage preparedMessage,SlackChatConfiguration chatConfiguration){
  SlackMessageHandle<SlackMessageReply> handle=new SlackMessageHandle<>(getNextMessageId());
  Map<String,String> arguments=new HashMap<>();
  arguments.put("String_Node_Str",authToken);
  arguments.put("String_Node_Str",channel.getId());
  arguments.put("String_Node_Str",preparedMessage.getMessage());
  if (chatConfiguration.isAsUser()) {
    arguments.put("String_Node_Str","String_Node_Str");
  }
  if (chatConfiguration.getAvatar() == Avatar.ICON_URL) {
    arguments.put("String_Node_Str",chatConfiguration.getAvatarDescription());
  }
  if (chatConfiguration.getAvatar() == Avatar.EMOJI) {
    arguments.put("String_Node_Str",chatConfiguration.getAvatarDescription());
  }
  if (chatConfiguration.getUserName() != null) {
    arguments.put("String_Node_Str",chatConfiguration.getUserName());
  }
  if (preparedMessage.getAttachments() != null && preparedMessage.getAttachments().length > 0) {
    arguments.put("String_Node_Str",SlackJSONAttachmentFormatter.encodeAttachments(preparedMessage.getAttachments()).toString());
  }
  if (!preparedMessage.isUnfurl()) {
    arguments.put("String_Node_Str","String_Node_Str");
    arguments.put("String_Node_Str","String_Node_Str");
  }
  if (preparedMessage.isLinkNames()) {
    arguments.put("String_Node_Str","String_Node_Str");
  }
  if (preparedMessage.getThreadTimestamp() != null) {
    arguments.put("String_Node_Str",preparedMessage.getThreadTimestamp());
    if (preparedMessage.isReplyBroadcast()) {
      arguments.put("String_Node_Str","String_Node_Str");
    }
  }
  postSlackCommand(arguments,CHAT_POST_MESSAGE_COMMAND,handle);
  return handle;
}

Fixed version (ground truth):
@Override public SlackMessageHandle<SlackMessageReply> sendMessage(SlackChannel channel,SlackPreparedMessage preparedMessage,SlackChatConfiguration chatConfiguration){
  if (channel == null) {
    throw new IllegalArgumentException("String_Node_Str");
  }
  SlackMessageHandle<SlackMessageReply> handle=new SlackMessageHandle<>(getNextMessageId());
  Map<String,String> arguments=new HashMap<>();
  arguments.put("String_Node_Str",authToken);
  arguments.put("String_Node_Str",channel.getId());
  arguments.put("String_Node_Str",preparedMessage.getMessage());
  if (chatConfiguration.isAsUser()) {
    arguments.put("String_Node_Str","String_Node_Str");
  }
  if (chatConfiguration.getAvatar() == Avatar.ICON_URL) {
    arguments.put("String_Node_Str",chatConfiguration.getAvatarDescription());
  }
  if (chatConfiguration.getAvatar() == Avatar.EMOJI) {
    arguments.put("String_Node_Str",chatConfiguration.getAvatarDescription());
  }
  if (chatConfiguration.getUserName() != null) {
    arguments.put("String_Node_Str",chatConfiguration.getUserName());
  }
  if (preparedMessage.getAttachments() != null && preparedMessage.getAttachments().length > 0) {
    arguments.put("String_Node_Str",SlackJSONAttachmentFormatter.encodeAttachments(preparedMessage.getAttachments()).toString());
  }
  if (!preparedMessage.isUnfurl()) {
    arguments.put("String_Node_Str","String_Node_Str");
    arguments.put("String_Node_Str","String_Node_Str");
  }
  if (preparedMessage.isLinkNames()) {
    arguments.put("String_Node_Str","String_Node_Str");
  }
  if (preparedMessage.getThreadTimestamp() != null) {
    arguments.put("String_Node_Str",preparedMessage.getThreadTimestamp());
    if (preparedMessage.isReplyBroadcast()) {
      arguments.put("String_Node_Str","String_Node_Str");
    }
  }
  postSlackCommand(arguments,CHAT_POST_MESSAGE_COMMAND,handle);
  return handle;
}