pythongh-109974: Fix threading lock_tests: adjust timeouts

* test_set_and_clear(): increase event wait()
  timeout. Remove sleep after Bunch.wait_for_started().
* BarrierTests.test_repr(): remove sleep after wait_for_started().
  Use way longer timeout for Barrier.wait() timeout.
* test_thread_leak() no longer needs to count
  len(threading.enumerate()): Bunch uses
  threading_helper.wait_threads_exit() internally which does it in
  wait_for_finished().

Lib/test/lock_tests.py

@@ -174,17 +174,10 @@ def test_thread_leak(self):
         def f():
             lock.acquire()
             lock.release()
-        n = len(threading.enumerate())
+
         # We run many threads in the hope that existing threads ids won't
         # be recycled.
         Bunch(f, 15).wait_for_finished()
-        if len(threading.enumerate()) != n:
-            # There is a small window during which a Thread instance's
-            # target function has finished running, but the Thread is still
-            # alive and registered.  Avoid spurious failures by waiting a
-            # bit more (seen on a buildbot).
-            time.sleep(0.4)
-            self.assertEqual(n, len(threading.enumerate()))
 
     def test_timeout(self):
         lock = self.locktype()
@@ -464,17 +457,15 @@ def f():
             self.assertTrue(r)
 
     def test_set_and_clear(self):
-        # Issue #13502: check that wait() returns true even when the event is
+        # gh-57711: check that wait() returns true even when the event is
         # cleared before the waiting thread is woken up.
         evt = self.eventtype()
         results = []
-        timeout = 0.250
         N = 5
         def f():
-            results.append(evt.wait(timeout * 4))
+            results.append(evt.wait(support.LONG_TIMEOUT))
         b = Bunch(f, N)
         b.wait_for_started()
-        time.sleep(timeout)
         evt.set()
         evt.clear()
         b.wait_for_finished()
@@ -636,7 +627,7 @@ def test_waitfor(self):
         state = 0
         def f():
             with cond:
-                result = cond.wait_for(lambda : state==4)
+                result = cond.wait_for(lambda: state == 4)
                 self.assertTrue(result)
                 self.assertEqual(state, 4)
         b = Bunch(f, 1)
@@ -660,6 +651,7 @@ def f():
                 self.assertFalse(result)
                 self.assertTimeout(dt, 0.1)
                 success.append(None)
+
         b = Bunch(f, 1)
         b.wait_for_started()
         # Only increment 3 times, so state == 4 is never reached.
@@ -1068,16 +1060,19 @@ def test_single_thread(self):
         b.wait()
 
     def test_repr(self):
+        timeout = support.LONG_TIMEOUT
         b = self.barriertype(3)
         self.assertRegex(repr(b), r"<\w+\.Barrier at .*: waiters=0/3>")
         def f():
-            b.wait(3)
+            b.wait(timeout)
         bunch = Bunch(f, 2)
+
         bunch.wait_for_started()
-        time.sleep(0.2)
         self.assertRegex(repr(b), r"<\w+\.Barrier at .*: waiters=2/3>")
-        b.wait(3)
+
+        b.wait(timeout)
         bunch.wait_for_finished()
         self.assertRegex(repr(b), r"<\w+\.Barrier at .*: waiters=0/3>")
+
         b.abort()
         self.assertRegex(repr(b), r"<\w+\.Barrier at .*: broken>")