Merge pull request #12 from justjasongreen/date_utils

Test date_utils (closes #8)

predictive_punter/date_utils.py

@@ -4,7 +4,11 @@
 def dates(date_from, date_to):
     """Iterate over all dates from date_from to date_to (inclusive)"""
 
+    time_delta = timedelta(days=1)
+    if date_from > date_to:
+        time_delta *= -1
+
     next_date = date_from
-    while next_date <= date_to:
+    while (date_from <= date_to and next_date <= date_to) or (date_from > date_to and next_date >= date_to):
         yield next_date
-        next_date += timedelta(days=1)
+        next_date += time_delta

tests/date_utils/dates_test.py

@@ -0,0 +1,43 @@
+from datetime import datetime
+
+from predictive_punter import date_utils
+
+
+def test_equal():
+    """The dates iterator should generate the expected date when date_from == date_to"""
+
+    expected_dates = [
+        datetime(2016, 2, 2)
+    ]
+
+    actual_dates = [date for date in date_utils.dates(datetime(2016, 2, 2), datetime(2016, 2, 2))]
+
+    assert actual_dates == expected_dates
+
+
+def test_forward():
+    """The dates iterator should generate the expected dates when date_from < date_to"""
+
+    expected_dates = [
+        datetime(2016, 2, 1),
+        datetime(2016, 2, 2),
+        datetime(2016, 2, 3)
+    ]
+
+    actual_dates = [date for date in date_utils.dates(datetime(2016, 2, 1), datetime(2016, 2, 3))]
+
+    assert actual_dates == expected_dates
+
+
+def test_reverse():
+    """The dates iterator should generate the expected dates when date_from > date_to"""
+
+    expected_dates = [
+        datetime(2016, 2, 3),
+        datetime(2016, 2, 2),
+        datetime(2016, 2, 1)
+    ]
+
+    actual_dates = [date for date in date_utils.dates(datetime(2016, 2, 3), datetime(2016, 2, 1))]
+
+    assert actual_dates == expected_dates