def f():

f()

try:

for depth in (10, 25, 50, 75, 100, 250, 1000):

for depth in (50, 75, 100, 250, 1000):

try:

sys.setrecursionlimit(depth)

except RecursionError:

# Issue #5392: test stack overflow after hitting recursion

# limit twice

self.assertRaises(RecursionError, f)

self.assertRaises(RecursionError, f)

with self.assertRaises(RecursionError):

f()

with self.assertRaises(RecursionError):

f()

finally:

sys.setrecursionlimit(oldlimit)

@test.support.cpython_only

def test_setrecursionlimit_recursion_depth(self):

# Issue #25274: Setting a low recursion limit must be blocked if the

# current recursion depth is already higher than the "lower-water

# mark". Otherwise, it may not be possible anymore to

# reset the overflowed flag to 0.

# current recursion depth is already higher than limit.

from _testinternalcapi import get_recursion_depth

sys.setrecursionlimit(1000)

for limit in (10, 25, 50, 75, 100, 150, 200):

# formula extracted from _Py_RecursionLimitLowerWaterMark()

if limit > 200:

depth = limit - 50

else:

depth = limit * 3 // 4

set_recursion_limit_at_depth(depth, limit)

set_recursion_limit_at_depth(limit, limit)

finally:

sys.setrecursionlimit(oldlimit)

# The error message is specific to CPython

@test.support.cpython_only

def test_recursionlimit_fatalerror(self):

# A fatal error occurs if a second recursion limit is hit when recovering

# from a first one.

code = textwrap.dedent("""

import sys

def f():

try:

f()

except RecursionError:

f()

sys.setrecursionlimit(%d)

f()""")

with test.support.SuppressCrashReport():

for i in (50, 1000):

sub = subprocess.Popen([sys.executable, '-c', code % i],

stderr=subprocess.PIPE)

err = sub.communicate()[1]

self.assertTrue(sub.returncode, sub.returncode)

self.assertIn(

b"Fatal Python error: _Py_CheckRecursiveCall: "

b"Cannot recover from stack overflow",

err)

def test_getwindowsversion(self):

# Raise SkipTest if sys doesn't have getwindowsversion attribute

test.support.get_attribute(sys, "getwindowsversion")