Remove exceeds_recursion_limit and get_c_recursion_limit. Use platform independent constants

Author: markshannon

Include/cpython/pystate.h

@@ -235,9 +235,9 @@ struct _ts {
    // higher stack memory usage than a release build: use a lower limit.
 #  if defined(__has_feature)  /* Clang */
     // Clang debug builds use a lot of stack space
-#    define Py_C_RECURSION_LIMIT (Py_C_STACK_SIZE / 2000)
+#    define Py_C_RECURSION_LIMIT (Py_C_STACK_SIZE / 4000)
 #  else
-#    define Py_C_RECURSION_LIMIT (Py_C_STACK_SIZE / 1000)
+#    define Py_C_RECURSION_LIMIT (Py_C_STACK_SIZE / 2000)
 #  endif
 #elif defined(_Py_ADDRESS_SANITIZER)
 #  define Py_C_RECURSION_LIMIT (Py_C_STACK_SIZE / 600)

Lib/test/list_tests.py

@@ -6,7 +6,7 @@
 from functools import cmp_to_key
 
 from test import seq_tests
-from test.support import ALWAYS_EQ, NEVER_EQ, get_c_recursion_limit, skip_emscripten_stack_overflow
+from test.support import ALWAYS_EQ, NEVER_EQ, skip_emscripten_stack_overflow
 
 
 class CommonTest(seq_tests.CommonTest):

Lib/test/mapping_tests.py

@@ -1,7 +1,7 @@
 # tests common to dict and UserDict
 import unittest
 import collections
-from test.support import get_c_recursion_limit, skip_emscripten_stack_overflow
+from test.support import skip_emscripten_stack_overflow
 
 
 class BasicTestMappingProtocol(unittest.TestCase):

Lib/test/support/__init__.py

@@ -56,7 +56,7 @@
     "run_with_tz", "PGO", "missing_compiler_executable",
     "ALWAYS_EQ", "NEVER_EQ", "LARGEST", "SMALLEST",
     "LOOPBACK_TIMEOUT", "INTERNET_TIMEOUT", "SHORT_TIMEOUT", "LONG_TIMEOUT",
-    "Py_DEBUG", "exceeds_recursion_limit", "get_c_recursion_limit",
+    "Py_DEBUG"
     "skip_on_s390x",
     "requires_jit_enabled",
     "requires_jit_disabled",
@@ -2623,20 +2623,6 @@ def adjust_int_max_str_digits(max_digits):
     finally:
         sys.set_int_max_str_digits(current)
 
-
-def get_c_recursion_limit():
-    try:
-        import _testcapi
-        return _testcapi.Py_C_RECURSION_LIMIT
-    except ImportError:
-        raise unittest.SkipTest('requires _testcapi')
-
-
-def exceeds_recursion_limit():
-    """For recursion tests, easily exceeds default recursion limit."""
-    return get_c_recursion_limit() * 20
-
-
 # Windows doesn't have os.uname() but it doesn't support s390x.
 is_s390x = hasattr(os, 'uname') and os.uname().machine == 's390x'
 skip_on_s390x = unittest.skipIf(is_s390x, 'skipped on s390x')

Lib/test/test_ast/test_ast.py

@@ -747,9 +747,9 @@ def next(self):
     @support.cpython_only
     @skip_emscripten_stack_overflow()
     def test_ast_recursion_limit(self):
-        fail_depth = support.exceeds_recursion_limit() * 2
+        fail_depth = 20_000
         crash_depth = 200_000
-        success_depth = support.get_c_recursion_limit()
+        success_depth = 200
         if _testinternalcapi is not None:
             remaining = _testinternalcapi.get_c_recursion_remaining()
             success_depth = min(success_depth, remaining)

Lib/test/test_capi/test_misc.py

@@ -408,7 +408,7 @@ def test_trashcan_subclass(self):
         # activated when its tp_dealloc is being called by a subclass
         from _testcapi import MyList
         L = None
-        for i in range(support.get_c_recursion_limit()):
+        for i in range(100):
             L = MyList((L,))
 
     @support.requires_resource('cpu')

Lib/test/test_collections.py

@@ -542,7 +542,7 @@ def test_odd_sizes(self):
         self.assertEqual(Dot(1)._replace(d=999), (999,))
         self.assertEqual(Dot(1)._fields, ('d',))
 
-        n = support.exceeds_recursion_limit()
+        n = 100_000
         names = list(set(''.join([choice(string.ascii_letters)
                                   for j in range(10)]) for i in range(n)))
         n = len(names)

Lib/test/test_compile.py

@@ -21,7 +21,7 @@
 
 from test import support
 from test.support import (script_helper, requires_debug_ranges, run_code,
-                          requires_specialization, get_c_recursion_limit)
+                          requires_specialization)
 from test.support.bytecode_helper import instructions_with_positions
 from test.support.os_helper import FakePath
 
@@ -123,7 +123,7 @@ def __getitem__(self, key):
     @unittest.skipIf(support.is_wasi, "exhausts limited stack on WASI")
     @support.skip_emscripten_stack_overflow()
     def test_extended_arg(self):
-        repeat = int(get_c_recursion_limit() * 0.9)
+        repeat = 100
         longexpr = 'x = x or ' + '-x' * repeat
         g = {}
         code = textwrap.dedent('''
@@ -713,7 +713,7 @@ def test_yet_more_evil_still_undecodable(self):
     @support.skip_emscripten_stack_overflow()
     def test_compiler_recursion_limit(self):
         # Compiler frames are small
-        limit = get_c_recursion_limit() * 3 // 2
+        limit = 100
         fail_depth = limit * 50
         crash_depth = limit * 200
         success_depth = limit

Lib/test/test_dict.py

@@ -8,7 +8,7 @@
 import unittest
 import weakref
 from test import support
-from test.support import import_helper, get_c_recursion_limit
+from test.support import import_helper
 
 
 class DictTest(unittest.TestCase):

Lib/test/test_dictviews.py

@@ -2,7 +2,7 @@
 import copy
 import pickle
 import unittest
-from test.support import exceeds_recursion_limit, skip_emscripten_stack_overflow
+from test.support import skip_emscripten_stack_overflow
 
 class DictSetTest(unittest.TestCase):
 
@@ -280,7 +280,7 @@ def test_recursive_repr(self):
     @skip_emscripten_stack_overflow()
     def test_deeply_nested_repr(self):
         d = {}
-        for i in range(exceeds_recursion_limit() * 2):
+        for i in range(100_000):
             d = {42: d.values()}
         self.assertRaises(RecursionError, repr, d)