Remove natsort

- Remove external requirement for 'natsort' and replace it with sorted() using
  a custom lambda as the 'key'.
- Added unit test checking that 'expanded' values are sorted as expected.

4 files changed, 14 insertions, 5 deletions

diff --git a/docs/CHANGES.rst b/docs/CHANGES.rst
index d735083..34dec96 100644
--- a/docs/CHANGES.rst
+++ b/docs/CHANGES.rst
@@ -4,7 +4,10 @@ Changelog
 1.0.9 (unreleased)
 ------------------
 
-- Nothing changed yet.
+- Remove external library ``natsort``.
+  Sorting of cron expression components now handled with ``sorted()`` with a custom ``key`` function.
+  [Kintyre]
+
 
 
 1.0.8 (2021-03-06)
@@ -107,7 +110,7 @@ Changelog
 -------------------
 
 - Make dateutil tz support more official
-  [lowell80]
+  [Kintyre]
 - Feat/support for day or
   [田口信元]
 
diff --git a/requirements/base.txt b/requirements/base.txt
index 56d1bf5..7ff05fa 100644
--- a/requirements/base.txt
+++ b/requirements/base.txt
@@ -1,4 +1,3 @@
 python_dateutil
 future
-natsort
 -e .
diff --git a/src/croniter/croniter.py b/src/croniter/croniter.py
index e5b8318..3d1001b 100644
--- a/src/croniter/croniter.py
+++ b/src/croniter/croniter.py
@@ -11,7 +11,6 @@ import datetime
 from dateutil.relativedelta import relativedelta
 from dateutil.tz import tzutc
 import calendar
-import natsort
 from future.utils import raise_from
 
 
@@ -642,7 +641,8 @@ class croniter(object):
                         nth_weekday_of_month[t].add(int(nth))
 
             res = set(res)
-            res = natsort.natsorted(res)
+            res = sorted(res, key=lambda i: "{:02}".format(i) if isinstance(i, int) else i)
+            # res = sorted(res)
             if len(res) == cls.LEN_MEANS_ALL[i]:
                 res = ['*']
 
diff --git a/src/croniter/tests/test_croniter.py b/src/croniter/tests/test_croniter.py
index 2bdd0c3..6eb5991 100755
--- a/src/croniter/tests/test_croniter.py
+++ b/src/croniter/tests/test_croniter.py
@@ -1313,6 +1313,13 @@ class CroniterRangeTest(base.TestCase):
         dt = croniter("0 0 * * *,sat#3", datetime(2019, 1, 14, 11, 0, 59, 999999)).get_next()
         self.assertEqual(1547856000.0, dt)
 
+    def test_confirm_sort(self):
+        m, h, d, mon, dow, s = range(6)
+        self.assertListEqual(croniter('0 8,22,10,23 0 0 0').expanded[h], [8, 10, 22, 23])
+        self.assertListEqual(croniter('0 0 25-L 0 0').expanded[d], [25, 26, 27, 28, 29, 30, 31])
+        self.assertListEqual(croniter("1 1 7,14,21,L * *").expanded[d], [7, 14, 21, "l"])
+        self.assertListEqual(croniter("0 0 * * *,sat#3").expanded[dow], ["*", 6])
+
 
 if __name__ == '__main__':
     unittest.main()