diff options
| -rw-r--r-- | Lib/test/support/__init__.py | 40 | ||||
| -rw-r--r-- | Lib/test/test_int.py | 58 | ||||
| -rw-r--r-- | Lib/test/test_re.py | 19 |
3 files changed, 75 insertions, 42 deletions
diff --git a/Lib/test/support/__init__.py b/Lib/test/support/__init__.py index 1d03ec0..401b2ce 100644 --- a/Lib/test/support/__init__.py +++ b/Lib/test/support/__init__.py @@ -2381,6 +2381,46 @@ def sleeping_retry(timeout, err_msg=None, /, delay = min(delay * 2, max_delay) +class CPUStopwatch: + """Context manager to roughly time a CPU-bound operation. + + Disables GC. Uses CPU time if it can (i.e. excludes sleeps & time of + other processes). + + N.B.: + - This *includes* time spent in other threads. + - Some systems only have a coarse resolution; check + stopwatch.clock_info.rseolution if. + + Usage: + + with ProcessStopwatch() as stopwatch: + ... + elapsed = stopwatch.seconds + resolution = stopwatch.clock_info.resolution + """ + def __enter__(self): + get_time = time.process_time + clock_info = time.get_clock_info('process_time') + if get_time() <= 0: # some platforms like WASM lack process_time() + get_time = time.monotonic + clock_info = time.get_clock_info('monotonic') + self.context = disable_gc() + self.context.__enter__() + self.get_time = get_time + self.clock_info = clock_info + self.start_time = get_time() + return self + + def __exit__(self, *exc): + try: + end_time = self.get_time() + finally: + result = self.context.__exit__(*exc) + self.seconds = end_time - self.start_time + return result + + @contextlib.contextmanager def adjust_int_max_str_digits(max_digits): """Temporarily change the integer string conversion length limit.""" diff --git a/Lib/test/test_int.py b/Lib/test/test_int.py index 0bf55fa..47fc50a 100644 --- a/Lib/test/test_int.py +++ b/Lib/test/test_int.py @@ -664,84 +664,78 @@ class IntStrDigitLimitsTests(unittest.TestCase): """Regression test: ensure we fail before performing O(N**2) work.""" maxdigits = sys.get_int_max_str_digits() assert maxdigits < 50_000, maxdigits # A test prerequisite. - get_time = time.process_time - if get_time() <= 0: # some platforms like WASM lack process_time() - get_time = time.monotonic huge_int = int(f'0x{"c"*65_000}', base=16) # 78268 decimal digits. digits = 78_268 - with support.adjust_int_max_str_digits(digits): - start = get_time() + with ( + support.adjust_int_max_str_digits(digits), + support.CPUStopwatch() as sw_convert): huge_decimal = str(huge_int) - seconds_to_convert = get_time() - start self.assertEqual(len(huge_decimal), digits) # Ensuring that we chose a slow enough conversion to measure. # It takes 0.1 seconds on a Zen based cloud VM in an opt build. # Some OSes have a low res 1/64s timer, skip if hard to measure. - if seconds_to_convert < 1/64: + if sw_convert.seconds < sw_convert.clock_info.resolution * 2: raise unittest.SkipTest('"slow" conversion took only ' - f'{seconds_to_convert} seconds.') + f'{sw_convert.seconds} seconds.') # We test with the limit almost at the size needed to check performance. # The performant limit check is slightly fuzzy, give it a some room. with support.adjust_int_max_str_digits(int(.995 * digits)): - with self.assertRaises(ValueError) as err: - start = get_time() + with ( + self.assertRaises(ValueError) as err, + support.CPUStopwatch() as sw_fail_huge): str(huge_int) - seconds_to_fail_huge = get_time() - start self.assertIn('conversion', str(err.exception)) - self.assertLessEqual(seconds_to_fail_huge, seconds_to_convert/2) + self.assertLessEqual(sw_fail_huge.seconds, sw_convert.seconds/2) # Now we test that a conversion that would take 30x as long also fails # in a similarly fast fashion. extra_huge_int = int(f'0x{"c"*500_000}', base=16) # 602060 digits. - with self.assertRaises(ValueError) as err: - start = get_time() + with ( + self.assertRaises(ValueError) as err, + support.CPUStopwatch() as sw_fail_extra_huge): # If not limited, 8 seconds said Zen based cloud VM. str(extra_huge_int) - seconds_to_fail_extra_huge = get_time() - start self.assertIn('conversion', str(err.exception)) - self.assertLess(seconds_to_fail_extra_huge, seconds_to_convert/2) + self.assertLess(sw_fail_extra_huge.seconds, sw_convert.seconds/2) def test_denial_of_service_prevented_str_to_int(self): """Regression test: ensure we fail before performing O(N**2) work.""" maxdigits = sys.get_int_max_str_digits() assert maxdigits < 100_000, maxdigits # A test prerequisite. - get_time = time.process_time - if get_time() <= 0: # some platforms like WASM lack process_time() - get_time = time.monotonic digits = 133700 huge = '8'*digits - with support.adjust_int_max_str_digits(digits): - start = get_time() + with ( + support.adjust_int_max_str_digits(digits), + support.CPUStopwatch() as sw_convert): int(huge) - seconds_to_convert = get_time() - start # Ensuring that we chose a slow enough conversion to measure. # It takes 0.1 seconds on a Zen based cloud VM in an opt build. # Some OSes have a low res 1/64s timer, skip if hard to measure. - if seconds_to_convert < 1/64: + if sw_convert.seconds < sw_convert.clock_info.resolution * 2: raise unittest.SkipTest('"slow" conversion took only ' - f'{seconds_to_convert} seconds.') + f'{sw_convert.seconds} seconds.') with support.adjust_int_max_str_digits(digits - 1): - with self.assertRaises(ValueError) as err: - start = get_time() + with ( + self.assertRaises(ValueError) as err, + support.CPUStopwatch() as sw_fail_huge): int(huge) - seconds_to_fail_huge = get_time() - start self.assertIn('conversion', str(err.exception)) - self.assertLessEqual(seconds_to_fail_huge, seconds_to_convert/2) + self.assertLessEqual(sw_fail_huge.seconds, sw_convert.seconds/2) # Now we test that a conversion that would take 30x as long also fails # in a similarly fast fashion. extra_huge = '7'*1_200_000 - with self.assertRaises(ValueError) as err: - start = get_time() + with ( + self.assertRaises(ValueError) as err, + support.CPUStopwatch() as sw_fail_extra_huge): # If not limited, 8 seconds in the Zen based cloud VM. int(extra_huge) - seconds_to_fail_extra_huge = get_time() - start self.assertIn('conversion', str(err.exception)) - self.assertLessEqual(seconds_to_fail_extra_huge, seconds_to_convert/2) + self.assertLessEqual(sw_fail_extra_huge.seconds, sw_convert.seconds/2) def test_power_of_two_bases_unlimited(self): """The limit does not apply to power of 2 bases.""" diff --git a/Lib/test/test_re.py b/Lib/test/test_re.py index 993a7d6..b1ac22c 100644 --- a/Lib/test/test_re.py +++ b/Lib/test/test_re.py @@ -1,7 +1,7 @@ from test.support import (gc_collect, bigmemtest, _2G, cpython_only, captured_stdout, check_disallow_instantiation, is_emscripten, is_wasi, - warnings_helper, SHORT_TIMEOUT) + warnings_helper, SHORT_TIMEOUT, CPUStopwatch) import locale import re import string @@ -2284,17 +2284,16 @@ class ReTests(unittest.TestCase): def test_search_anchor_at_beginning(self): s = 'x'*10**7 - start = time.perf_counter() - for p in r'\Ay', r'^y': - self.assertIsNone(re.search(p, s)) - self.assertEqual(re.split(p, s), [s]) - self.assertEqual(re.findall(p, s), []) - self.assertEqual(list(re.finditer(p, s)), []) - self.assertEqual(re.sub(p, '', s), s) - t = time.perf_counter() - start + with CPUStopwatch() as stopwatch: + for p in r'\Ay', r'^y': + self.assertIsNone(re.search(p, s)) + self.assertEqual(re.split(p, s), [s]) + self.assertEqual(re.findall(p, s), []) + self.assertEqual(list(re.finditer(p, s)), []) + self.assertEqual(re.sub(p, '', s), s) # Without optimization it takes 1 second on my computer. # With optimization -- 0.0003 seconds. - self.assertLess(t, 0.1) + self.assertLess(stopwatch.seconds, 0.1) def test_possessive_quantifiers(self): """Test Possessive Quantifiers |