new features for ExponentialBackoff

satella/time.py

@@ -421,13 +421,23 @@ class ExponentialBackoff:
                 return self.unavailable_until - t
 
     @property
-    def available(self) -> bool:
+    def ready_for_next_check(self) -> bool:
         """
-        :return: Is the service healthy, ie. last time that instance was informed a
-            :meth:`~satella.time.ExponentialBackoff.success` was called rather
-            than :meth::meth:`~satella.time.ExponentialBackoff.failure`?
+        :return: Has  :meth:`~satella.time.ExponentialBackoff.failure` been called only
+            in the last waiting period?
         """
-        return self.unavailable_until is None
+        if self.unavailable_until is None:
+            return True
+        elif time.monotonic() > self.unavailable_until:
+            self.unavailable_until = None
+            return True
+        else:
+            return False
+
+    @property
+    def available(self) -> bool:
+        """Was the status of the last call :code:`success`?"""
+        return self.counter == 0
 
     def success(self):
         """

tests/test_time.py

@@ -21,6 +21,7 @@ class TestTime(unittest.TestCase):
             with measure() as m:
                 eb.wait_until_available(2.5)
                 self.assertTrue(eb.available)
+            self.assertLessEqual(m(), 1.5)
 
         eb.failed()
         do_test()
@@ -32,10 +33,13 @@ class TestTime(unittest.TestCase):
 
         eb.failed()
         self.assertFalse(eb.available)
+        self.assertFalse(eb.ready_for_next_check)
         with measure() as m:
             eb.wait_until_available()
+        self.assertTrue(eb.ready_for_next_check)
         self.assertGreaterEqual(m(), 2)
         eb.success()
+        self.assertTrue(eb.ready_for_next_check)
         self.assertTrue(eb.available)
         eb.failed()
         self.assertFalse(eb.available)