Add tests and bugfix for b'' messages appearing in python3.

I added unicode and non-unicode message testing for the output() method
on RTMBot. I'm concerned about why the encode('ascii', 'ignore') was
there in the first place, but not having it seems to do the right
thing...

requirements-dev.txt

@@ -1,6 +1,7 @@
 coveralls==1.1
 ipdb==0.9.3
 ipython==4.1.2
+mock==2.0.0
 pdbpp==0.8.3
 pytest>=2.8.2
 pytest-cov==2.2.1

rtmbot/core.py

@@ -101,7 +101,7 @@ class RtmBot(object):
                     if limiter:
                         time.sleep(.1)
                         limiter = False
-                    message = output[1].encode('ascii', 'ignore')
+                    message = output[1]
                     channel.send_message("{}".format(message))
                     limiter = True
 

tests/test_example.py

@@ -1,2 +0,0 @@
-def test_example():
-	assert True

tests/test_rtmbot_core.py

@@ -1,15 +1,25 @@
+# -*- coding: utf-8 -*-
+try:
+    from unittest.mock import Mock
+except ImportError:
+    from mock import Mock
+
 from testfixtures import LogCapture
 from rtmbot.core import RtmBot
 
+def init_rtmbot():
+    ''' Initializes an instance of RTMBot with some default values '''
+    rtmbot = RtmBot({
+        'SLACK_TOKEN': 'test-12345',
+        'BASE_PATH': '/tmp/',
+        'LOGFILE': '/tmp/rtmbot.log',
+        'DEBUG': True
+    })
+    return rtmbot
 
 def test_init():
     with LogCapture() as l:
-        rtmbot = RtmBot({
-            'SLACK_TOKEN': 'test-12345',
-            'BASE_PATH': '/tmp/',
-            'LOGFILE': '/tmp/rtmbot.log',
-            'DEBUG': True
-        })
+        rtmbot = init_rtmbot()
 
     assert rtmbot.token == 'test-12345'
     assert rtmbot.directory == '/tmp/'
@@ -18,3 +28,32 @@ def test_init():
     l.check(
         ('root', 'INFO', 'Initialized in: /tmp/')
     )
+
+def test_output():
+    ''' Test that sending a message behaves as expected '''
+    rtmbot = init_rtmbot()
+
+    # Mock the slack_client object
+    slackclient_mock = Mock()
+    channel_mock = Mock()
+    slackclient_mock.server.channels.find.return_value = channel_mock
+    rtmbot.slack_client = slackclient_mock
+
+    # mock the plugin object to return a sample response
+    plugin_mock = Mock()
+    plugin_mock.do_output.return_value = [['C12345678', 'test message']]
+    rtmbot.bot_plugins.append(plugin_mock)
+
+    rtmbot.output()
+
+
+    # test that the output matches the expected value
+    channel_mock.send_message.assert_called_with('test message')
+
+    # test that unicode messages work as expected
+    channel_mock.reset_mock()
+    plugin_mock.reset_mock()
+    plugin_mock.do_output.return_value = [['C12345678', '🚀 testing']]
+    rtmbot.output()
+
+    channel_mock.send_message.assert_called_with('🚀 testing')