Added a unit test file.

* Currently just tests one function: calculate_csat()
* Confirms old & new algorithm for a couple of test cases
* Baked in an exception that gets raised for pages with no yes or no
votes.
* added `.pyc` and `__pycache__` to `.gitignore` in order to avoid
synching unreadable content to git.

.gitignore

@@ -1,5 +1,7 @@
 *~
 .*.swp
+*.pyc
+__pycache__
 .DS_Store
 generate/generate
 Railroad.jar

scripts/docs_csat.py

@@ -191,7 +191,7 @@ def create_dict(response, dict):
 weighted_csats = dict()
 
 
-def calculate_csat(no_votes, yes_votes, pageviews, blacklist):
+def calculate_csat(no_votes, yes_votes, pageviews):
 
     # Remove blacklisted pages.
     for p in blacklist:
@@ -257,7 +257,7 @@ def main():
     print()
     print(
         'Docs CSAT (basic, weighted):',
-        calculate_csat(no_votes, yes_votes, pageviews, blacklist)
+        calculate_csat(no_votes, yes_votes, pageviews)
     )
     print()
 

scripts/test_docs_csat.py

@@ -0,0 +1,28 @@
+#!/usr/bin/env python
+
+import unittest
+import docs_csat as dc
+
+
+class TestDocsCSAT(unittest.TestCase):
+
+    def test_calculate_csat(self):
+        no_votes = {"page1": 1, "page2": 0, "page3": 1, "page4": 10}
+        yes_votes = {"page2": 10, "page3": 10, "page5": 1, "page6": 0}
+        pageviews = {"page2": 1000, "page4": 10}
+        # Raises ZeroDivisionError from wegihted CSAT section, line
+        # `average_csats[k] = yes / total`
+        self.assertRaises(ZeroDivisionError, dc.calculate_csat, no_votes,
+                          yes_votes, pageviews)
+
+        no_votes = {"page1": 1, "page2": 0, "page3": 1, "page4": 10}  # 12
+        yes_votes = {"page2": 10, "page3": 10, "page5": 1, "page6": 1}  # 22
+        pageviews = {"page2": 1000, "page4": 10}  # 1000 yes, 10 no
+        basic_csat, weighted_csat = dc.calculate_csat(no_votes, yes_votes,
+                                                      pageviews)
+        self.assertEqual(basic_csat, 22 / (12 + 22))
+        self.assertEqual(weighted_csat, 1000 / (1000 + 10))
+
+
+if __name__ == '__main__':
+    unittest.main()