IRC: Error sending messages bigger than 512 bytes. #989

In order to let us help you better, please fill out the following fields as best you can:

I am...

• Reporting a bug
• Suggesting a new feature
• Requesting help with running my bot
• Requesting help writing plugins
• Here about something else

I am running...

• Errbot version: 4.3.7
• OS version: Fedora 25
• Python version: 3.5
• Using a virtual environment: yes

Issue description

If the response of the bot has more than 512 bytes there is some complain from the backend:

Computer says nooo. See logs for details:
Messages limited to 512 bytes including CR/LF

Full backtrace from the log:

2017-04-11 21:01:27,355 ERROR errbot.core An error happened while processing a message ("gary test"): Traceback (most recent call last):
File "/home/qlixed/src/gary/lib/python3.5/site-packages/errbot/core.py", line 453, in _execute_and_send
self.send_simple_reply(mess, self.process_template(template_name, reply), private)
File "/home/qlixed/src/gary/lib/python3.5/site-packages/errbot/core.py", line 198, in send_simple_reply
self.split_and_send_message(reply)
File "/home/qlixed/src/gary/lib/python3.5/site-packages/errbot/core.py", line 163, in split_and_send_message
self.send_message(partial_message)
File "/home/qlixed/src/gary/lib/python3.5/site-packages/errbot/backends/irc.py", line 672, in send_message
msg_func(msg_to, line)
File "/home/qlixed/src/gary/lib/python3.5/site-packages/errbot/utils.py", line 235, in rate_limited_function
ret = func(*args, **kargs)
File "/home/qlixed/src/gary/lib/python3.5/site-packages/errbot/backends/irc.py", line 426, in send_private_message
self.connection.privmsg(to, line)
File "/home/qlixed/src/gary/lib/python3.5/site-packages/irc/client.py", line 885, in privmsg
self.send_raw("PRIVMSG %s :%s" % (target, text))
File "/home/qlixed/src/gary/lib/python3.5/site-packages/irc/client.py", line 921, in send_raw
sender(self._prep_message(string))
File "/home/qlixed/src/gary/lib/python3.5/site-packages/irc/client.py", line 909, in _prep_message
raise MessageTooLong(msg)
irc.client.MessageTooLong: Messages limited to 512 bytes including CR/LF
"
Traceback (most recent call last):
File "/home/qlixed/src/gary/lib/python3.5/site-packages/errbot/core.py", line 453, in _execute_and_send
self.send_simple_reply(mess, self.process_template(template_name, reply), private)
File "/home/qlixed/src/gary/lib/python3.5/site-packages/errbot/core.py", line 198, in send_simple_reply
self.split_and_send_message(reply)
File "/home/qlixed/src/gary/lib/python3.5/site-packages/errbot/core.py", line 163, in split_and_send_message
self.send_message(partial_message)
File "/home/qlixed/src/gary/lib/python3.5/site-packages/errbot/backends/irc.py", line 672, in send_message
msg_func(msg_to, line)
File "/home/qlixed/src/gary/lib/python3.5/site-packages/errbot/utils.py", line 235, in rate_limited_function
ret = func(*args, **kargs)
File "/home/qlixed/src/gary/lib/python3.5/site-packages/errbot/backends/irc.py", line 426, in send_private_message
self.connection.privmsg(to, line)
File "/home/qlixed/src/gary/lib/python3.5/site-packages/irc/client.py", line 885, in privmsg
self.send_raw("PRIVMSG %s :%s" % (target, text))
File "/home/qlixed/src/gary/lib/python3.5/site-packages/irc/client.py", line 921, in send_raw
sender(self._prep_message(string))
File "/home/qlixed/src/gary/lib/python3.5/site-packages/irc/client.py", line 909, in _prep_message
raise MessageTooLong(msg)
irc.client.MessageTooLong: Messages limited to 512 bytes including CR/LF

Steps to reproduce

Make any response from the bot with a string with len()>512

Additional info

It suppose to cut the message in 510 bytes chunks when call self.split_and_send_message, but apparently is not working.