support object with __float__ defined in time.sleep

Author: chaope

Lib/test/test_time.py

@@ -180,6 +180,38 @@ def test_sleep(self):
             with self.subTest(value=value):
                 time.sleep(value)
 
+        class IndexLike:
+            def __init__(self, value):
+                self.value = int(value)
+            def __index__(self):
+                return self.value
+        index_like = IndexLike(1)
+
+        with self.subTest(value = index_like):
+            self._test_sleep_duration(index_like)
+
+        class FloatLike:
+            def __init__(self, value):
+                self.value = float(value)
+            def __float__(self):
+                return self.value
+        float_like = FloatLike(0.5)
+
+
+        with self.subTest(value = float_like):
+            self._test_sleep_duration(float_like)
+
+    def _test_sleep_duration(self, secs):
+        t1 = time.monotonic()
+        time.sleep(secs)
+        t2 = time.monotonic()
+        dt = t2 - t1
+        self.assertGreater(t2, t1)
+        # bpo-20101: tolerate a difference of 50 ms because of bad timer
+        # resolution on Windows
+        self.assertTrue(float(secs) - 0.05 <= dt)
+
+
     def test_epoch(self):
         # bpo-43869: Make sure that Python use the same Epoch on all platforms:
         # January 1, 1970, 00:00:00 (UTC).

Misc/NEWS.d/next/Library/2025-12-19-16-28-44.gh-issue-79888.ib0rM-.rst

@@ -0,0 +1 @@
+support object with __float__ defined in time.sleep

Python/pytime.c

@@ -584,6 +584,17 @@ pytime_from_object(PyTime_t *tp, PyObject *obj, _PyTime_round_t round,
         *tp = ns;
         return 0;
     }
+    else if (PyFloat_Check(obj)) {
+        double d = PyFloat_AsDouble(obj);
+        if (d == -1 && PyErr_Occurred()) {
+            return -1;
+        }
+        if (isnan(d)) {
+            PyErr_SetString(PyExc_ValueError, "Invalid value NaN (not a number)");
+            return -1;
+        }
+        return pytime_from_double(tp, d, round, unit_to_ns);
+    }
     else {
         double d;
         d = PyFloat_AsDouble(obj);