improve time.sleep() tests

python · picnixz · Dec 26, 2024 · Dec 26, 2024 · Dec 26, 2024 · Dec 26, 2024
commit f6a817fe31aea1822091afe2c45e15a27fcb602b
@@ -158,10 +158,46 @@ def test_conversions(self):
         self.assertEqual(int(time.mktime(time.localtime(self.t))),
                          int(self.t))
 
-    def test_sleep(self):
+    def test_sleep_exceptions(self):
+        self.assertRaises(TypeError, time.sleep, [])
+        self.assertRaises(TypeError, time.sleep, "a")
+        self.assertRaises(TypeError, time.sleep, complex(0, 0))
+
         self.assertRaises(ValueError, time.sleep, -2)
         self.assertRaises(ValueError, time.sleep, -1)
-        time.sleep(1.2)
+        self.assertRaises(ValueError, time.sleep, -0.1)
+
+    def test_sleep(self):
+        for value in [-0.0, 0, 0.0, 1e-6, 1, 1.2]:
+            with self.subTest(value=value):
+                time.sleep(value)
+
+    @unittest.skipIf(support.MS_WINDOWS, 'test only for non-Windows platforms')
+    def test_sleep_zero_posix(self):
+        # Test that time.sleep(0) does not accumulate delays.
+
+        N1 = 1000  # small number of samples for time.sleep(eps) with eps > 0
+        N2 = 100_000  # large number of samples for time.sleep(0)
+
+        # Compute how long time.sleep() takes for the 'time' clock resolution.
+        # We expect the result to be around 50 us for a nanosecond resolution.
+        eps = time.get_clock_info('time').resolution
+        max_dt_ns = self.stat_for_test_sleep(N1, time.sleep, eps)
+
+        # We expect a gap between time.sleep(0) and time.sleep(eps).
+        avg_dt_ns = self.stat_for_test_sleep(N2, time.sleep, 0)
+        self.assertLess(avg_dt_ns, max_dt_ns)
+
+    @staticmethod
+    def stat_for_test_sleep(n_samples, func, *args, **kwargs):
+        """Compute the average (ns) time execution of func(*args, **kwargs)."""
+        samples = []
+        for _ in range(int(n_samples)):
+            t0 = time.monotonic_ns()
+            func(*args, **kwargs)
+            t1 = time.monotonic_ns()
+            samples.append(t1 - t0)
+        return math.fsum(samples) / n_samples
 
     def test_epoch(self):
         # bpo-43869: Make sure that Python use the same Epoch on all platforms: