Merge pull request #60 from josegonzalez/issue-57

Implement step cron with a variable base

Author: kiorky

src/croniter/croniter.py

@@ -8,6 +8,7 @@
 from dateutil.relativedelta import relativedelta
 from dateutil.tz import tzutc
 
+step_search_re = re.compile(r'^([^-]+)-([^-/]+)(/(.*))?$')
 search_re = re.compile(r'^([^-]+)-([^-/]+)(/(.*))?$')
 only_int_re = re.compile(r'^\d+$')
 any_int_re = re.compile(r'^\d+')
@@ -76,12 +77,18 @@ def __init__(self, expr_format, start_time=None, ret_type=float):
 
             while len(e_list) > 0:
                 e = e_list.pop()
-                t = re.sub(r'^\*(/.+)$', r'%d-%d\1' % (
+                t = re.sub(r'^\*(\/.+)$', r'%d-%d\1' % (
                     self.RANGES[i][0],
                     self.RANGES[i][1]),
                     str(e))
                 m = search_re.search(t)
 
+                if not m:
+                    t = re.sub(r'^(.+)\/(.+)$', r'\1-%d/\2' % (
+                        self.RANGES[i][1]),
+                        str(e))
+                    m = step_search_re.search(t)
+
                 if m:
                     (low, high, step) = m.group(1), m.group(2), m.group(4) or 1
 

src/croniter/tests/test_croniter.py

@@ -233,7 +233,7 @@ def testError(self):
         self.assertRaises(ValueError, croniter, '* * * janu-jun *')
 
     def testSundayToThursdayWithAlphaConversion(self):
-        base = datetime(2010, 8, 25, 15, 56) #wednesday
+        base = datetime(2010, 8, 25, 15, 56)  # wednesday
         itr = croniter("30 22 * * sun-thu", base)
         next = itr.get_next(datetime)
 
@@ -395,6 +395,34 @@ def test_bug34(self):
         itr = croniter('* * 31 2 *', base)
         n1 = itr.get_next(datetime)
 
+    def testBug57(self):
+        base = datetime(2012, 2, 24, 0, 0, 0)
+        itr = croniter('0 4/6 * * *', base)
+        n1 = itr.get_next(datetime)
+        self.assertEqual(n1.hour, 4)
+        self.assertEqual(n1.minute, 0)
+        self.assertEqual(n1.month, 2)
+        self.assertEqual(n1.day, 24)
+
+        n1 = itr.get_prev(datetime)
+        self.assertEqual(n1.hour, 22)
+        self.assertEqual(n1.minute, 0)
+        self.assertEqual(n1.month, 2)
+        self.assertEqual(n1.day, 23)
+
+        itr = croniter('0 0/6 * * *', base)
+        n1 = itr.get_next(datetime)
+        self.assertEqual(n1.hour, 6)
+        self.assertEqual(n1.minute, 0)
+        self.assertEqual(n1.month, 2)
+        self.assertEqual(n1.day, 24)
+
+        n1 = itr.get_prev(datetime)
+        self.assertEqual(n1.hour, 0)
+        self.assertEqual(n1.minute, 0)
+        self.assertEqual(n1.month, 2)
+        self.assertEqual(n1.day, 24)
+
     def test_rangeGenerator(self):
         base = datetime(2013, 3, 4, 0, 0)
         itr = croniter('1-9/2 0 1 * *', base)