gh-127146: Emscripten: Skip segfaults in test suite (#127151)

Added skips for tests known to cause problems when running on Emscripten. 
These mostly relate to the limited stack depth on Emscripten.

Author: hoodmane

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
+from test.support import ALWAYS_EQ, NEVER_EQ, get_c_recursion_limit, skip_emscripten_stack_overflow
 
 
 class CommonTest(seq_tests.CommonTest):
@@ -59,6 +59,7 @@ def test_repr(self):
         self.assertEqual(str(a2), "[0, 1, 2, [...], 3]")
         self.assertEqual(repr(a2), "[0, 1, 2, [...], 3]")
 
+    @skip_emscripten_stack_overflow()
     def test_repr_deep(self):
         a = self.type2test([])
         for i in range(get_c_recursion_limit() + 1):

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
+from test.support import get_c_recursion_limit, skip_emscripten_stack_overflow
 
 
 class BasicTestMappingProtocol(unittest.TestCase):
@@ -622,6 +622,7 @@ def __repr__(self):
         d = self._full_mapping({1: BadRepr()})
         self.assertRaises(Exc, repr, d)
 
+    @skip_emscripten_stack_overflow()
     def test_repr_deep(self):
         d = self._empty_mapping()
         for i in range(get_c_recursion_limit() + 1):

Lib/test/support/__init__.py

@@ -535,6 +535,9 @@ def skip_android_selinux(name):
 is_emscripten = sys.platform == "emscripten"
 is_wasi = sys.platform == "wasi"
 
+def skip_emscripten_stack_overflow():
+    return unittest.skipIf(is_emscripten, "Exhausts limited stack on Emscripten")
+
 is_apple_mobile = sys.platform in {"ios", "tvos", "watchos"}
 is_apple = is_apple_mobile or sys.platform == "darwin"
 

Lib/test/test_ast/test_ast.py

@@ -18,7 +18,7 @@
     _testinternalcapi = None
 
 from test import support
-from test.support import os_helper, script_helper
+from test.support import os_helper, script_helper, skip_emscripten_stack_overflow
 from test.support.ast_helper import ASTTestMixin
 from test.test_ast.utils import to_tuple
 from test.test_ast.snippets import (
@@ -745,6 +745,7 @@ def next(self):
         enum._test_simple_enum(_Precedence, ast._Precedence)
 
     @support.cpython_only
+    @skip_emscripten_stack_overflow()
     def test_ast_recursion_limit(self):
         fail_depth = support.exceeds_recursion_limit()
         crash_depth = 100_000
@@ -1661,13 +1662,15 @@ def test_level_as_none(self):
         exec(code, ns)
         self.assertIn('sleep', ns)
 
+    @skip_emscripten_stack_overflow()
     def test_recursion_direct(self):
         e = ast.UnaryOp(op=ast.Not(), lineno=0, col_offset=0, operand=ast.Constant(1))
         e.operand = e
         with self.assertRaises(RecursionError):
             with support.infinite_recursion():
                 compile(ast.Expression(e), "<test>", "eval")
 
+    @skip_emscripten_stack_overflow()
     def test_recursion_indirect(self):
         e = ast.UnaryOp(op=ast.Not(), lineno=0, col_offset=0, operand=ast.Constant(1))
         f = ast.UnaryOp(op=ast.Not(), lineno=0, col_offset=0, operand=ast.Constant(1))

Lib/test/test_call.py

@@ -1,6 +1,6 @@
 import unittest
 from test.support import (cpython_only, is_wasi, requires_limited_api, Py_DEBUG,
-                          set_recursion_limit, skip_on_s390x)
+                          set_recursion_limit, skip_on_s390x, skip_emscripten_stack_overflow)
 try:
     import _testcapi
 except ImportError:
@@ -1038,6 +1038,7 @@ class TestRecursion(unittest.TestCase):
     @skip_on_s390x
     @unittest.skipIf(is_wasi and Py_DEBUG, "requires deep stack")
     @unittest.skipIf(_testcapi is None, "requires _testcapi")
+    @skip_emscripten_stack_overflow()
     def test_super_deep(self):
 
         def recurse(n):

Lib/test/test_capi/test_misc.py

@@ -2137,6 +2137,7 @@ def test_py_config_isoloated_per_interpreter(self):
         # test fails, assume that the environment in this process may
         # be altered and suspect.
 
+    @requires_subinterpreters
     @unittest.skipUnless(hasattr(os, "pipe"), "requires os.pipe()")
     def test_configured_settings(self):
         """

Lib/test/test_class.py

@@ -1,7 +1,7 @@
 "Test the functionality of Python classes implementing operators."
 
 import unittest
-from test.support import cpython_only, import_helper, script_helper
+from test.support import cpython_only, import_helper, script_helper, skip_emscripten_stack_overflow
 
 testmeths = [
 
@@ -554,6 +554,7 @@ class Custom:
         self.assertFalse(hasattr(o, "__call__"))
         self.assertFalse(hasattr(c, "__call__"))
 
+    @skip_emscripten_stack_overflow()
     def testSFBug532646(self):
         # Test for SF bug 532646
 

Lib/test/test_compile.py

@@ -121,6 +121,7 @@ def __getitem__(self, key):
         self.assertEqual(d['z'], 12)
 
     @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)
         longexpr = 'x = x or ' + '-x' * repeat
@@ -709,6 +710,7 @@ def test_yet_more_evil_still_undecodable(self):
 
     @support.cpython_only
     @unittest.skipIf(support.is_wasi, "exhausts limited stack on WASI")
+    @support.skip_emscripten_stack_overflow()
     def test_compiler_recursion_limit(self):
         # Expected limit is Py_C_RECURSION_LIMIT
         limit = get_c_recursion_limit()

Lib/test/test_copy.py

@@ -371,6 +371,7 @@ def test_deepcopy_list(self):
         self.assertIsNot(x, y)
         self.assertIsNot(x[0], y[0])
 
+    @support.skip_emscripten_stack_overflow()
     def test_deepcopy_reflexive_list(self):
         x = []
         x.append(x)
@@ -398,6 +399,7 @@ def test_deepcopy_tuple_of_immutables(self):
         y = copy.deepcopy(x)
         self.assertIs(x, y)
 
+    @support.skip_emscripten_stack_overflow()
     def test_deepcopy_reflexive_tuple(self):
         x = ([],)
         x[0].append(x)
@@ -415,6 +417,7 @@ def test_deepcopy_dict(self):
         self.assertIsNot(x, y)
         self.assertIsNot(x["foo"], y["foo"])
 
+    @support.skip_emscripten_stack_overflow()
     def test_deepcopy_reflexive_dict(self):
         x = {}
         x['foo'] = x

Lib/test/test_descr.py

@@ -3663,6 +3663,7 @@ def f(a): return a
                            encoding='latin1', errors='replace')
         self.assertEqual(ba, b'abc\xbd?')
 
+    @support.skip_emscripten_stack_overflow()
     def test_recursive_call(self):
         # Testing recursive __call__() by setting to instance of class...
         class A(object):
@@ -3942,6 +3943,7 @@ def __del__(self):
         # it as a leak.
         del C.__del__
 
+    @unittest.skipIf(support.is_emscripten, "Seems to works in Pyodide?")
     def test_slots_trash(self):
         # Testing slot trash...
         # Deallocating deeply nested slotted trash caused stack overflows
@@ -4864,6 +4866,7 @@ class Thing:
                 # CALL_METHOD_DESCRIPTOR_O
                 deque.append(thing, thing)
 
+    @support.skip_emscripten_stack_overflow()
     def test_repr_as_str(self):
         # Issue #11603: crash or infinite loop when rebinding __str__ as
         # __repr__.