Issue dbader#319: be able to skip a job

Author: chino540off

schedule/__init__.py

@@ -73,6 +73,13 @@ class CancelJob(object):
     pass
 
 
+class SkipJob(object):
+    """
+    Can be returned from a job to skip a run.
+    """
+    pass
+
+
 class Scheduler(object):
     """
     Objects instantiated by the :class:`Scheduler <Scheduler>` are
@@ -483,7 +490,8 @@ def run(self):
         """
         logger.info('Running job %s', self)
         ret = self.job_func()
-        self.last_run = datetime.datetime.now()
+        if not isinstance(ret, SkipJob) and ret is not SkipJob:
+            self.last_run = datetime.datetime.now()
         self._schedule_next_run()
         return ret
 

test_schedule.py

@@ -444,6 +444,31 @@ def stop_job():
         schedule.run_all()
         assert len(schedule.jobs) == 0
 
+    def test_skip_job(self):
+        skip = True
+
+        def skip_job():
+            if skip:
+                return schedule.SkipJob
+            else:
+                return None
+
+        job = every().second.do(skip_job)
+
+        assert len(schedule.jobs) == 1
+        assert job.last_run is None
+
+        schedule.run_all()
+
+        assert len(schedule.jobs) == 1
+        assert job.last_run is None
+
+        skip = False
+        schedule.run_all()
+
+        assert len(schedule.jobs) == 1
+        assert job.last_run is not None
+
     def test_tag_type_enforcement(self):
         job1 = every().second.do(make_mock_job(name='job1'))
         self.assertRaises(TypeError, job1.tag, {})