fix bug when using @comment with a comma but bad duration syntax.

Bantracker/plugin.py

@@ -107,6 +107,9 @@ timeUnits = FuzzyDict({
 def readTimeDelta(s):
     """convert a string like "2 days" or "1h2d3w" into seconds"""
     # split number and words
+    if not s:
+        raise ValueError(s)
+
     digit = string = number = None
     seconds = 0
     for c in s:
@@ -137,6 +140,9 @@ def readTimeDelta(s):
             string += c
 
     # check last string
+    if string is None:
+        raise ValueError(s)
+
     if string.isdigit():
         seconds += int(string)
     else:

Bantracker/test.py

@@ -130,6 +130,8 @@ class BantrackerTestCase(ChannelPluginTestCase):
         self.assertResponse('comment 1', 'No comments recorded for ban 1')
         self.assertResponse('comment 1 this is a test', 'The operation succeeded.')
         self.assertRegexp('comment 1', 'test: this is a test$')
+        self.assertResponse('comment 1 this is a test, another test',
+                            'The operation succeeded.')
 
     def testMultiComment(self):
         self.feedBan('asd!*@*')