Ensure isinstance is unaffected by sys.setprofile for Concatenate[] and Unpack[] aliases; run PyPy tests under coverage

.github/workflows/ci.yml

@@ -67,13 +67,11 @@ jobs:
  allow-prereleases: true
 
  - name: Install coverage
- if: ${{ !startsWith(matrix.python-version, 'pypy') }}
  run: |
  # Be wary that this does not install typing_extensions in the future
  pip install coverage
 
  - name: Test typing_extensions with coverage
- if: ${{ !startsWith(matrix.python-version, 'pypy') }}
  run: |
  # Be wary of running `pip install` here, since it becomes easy for us to
  # accidentally pick up typing_extensions as installed by a dependency
@@ -82,18 +80,9 @@ jobs:
  # Run tests under coverage
  export COVERAGE_FILE=.coverage_${{ matrix.python-version }}
  python -m coverage run -m unittest test_typing_extensions.py
- - name: Test typing_extensions no coverage on pypy
- if: ${{ startsWith(matrix.python-version, 'pypy') }}
- run: |
- # Be wary of running `pip install` here, since it becomes easy for us to
- # accidentally pick up typing_extensions as installed by a dependency
- cd src
- python --version # just to make sure we're running the right one
- python -m unittest test_typing_extensions.py
 
  - name: Archive code coverage results
  id: archive-coverage
- if: ${{ !startsWith(matrix.python-version, 'pypy') }}
  uses: actions/upload-artifact@v4
  with:
  name: .coverage_${{ matrix.python-version }}

CHANGELOG.md

@@ -1,5 +1,11 @@
 # Unreleased
 
+- Fix incorrect behaviour on Python 3.9 and Python 3.10 that meant that
+ calling `isinstance` with `typing_extensions.Concatenate[...]` or
+ `typing_extensions.Unpack[...]` as the first argument could have a different
+ result in some situations depending on whether or not a profiling function had been
+ set using `sys.setprofile`. This affected both CPython and PyPy implementations.
+ Patch by Brian Schubert.
 - Fix `__init_subclass__()` behavior in the presence of multiple inheritance involving
  an `@deprecated`-decorated base class. Backport of CPython PR
  [#138210](https://github.com/python/cpython/pull/138210) by Brian Schubert.

src/test_typing_extensions.py

@@ -6230,6 +6230,47 @@ def test_is_param_expr(self):
  self.assertTrue(typing._is_param_expr(concat))
  self.assertTrue(typing._is_param_expr(typing_concat))
 
+ def test_isinstance_results_unaffected_by_presence_of_tracing_function(self):
+ # See https://github.com/python/typing_extensions/issues/661
+
+ code = textwrap.dedent(
+ """\
+ import sys, typing
+
+ def trace_call(*args):
+ return trace_call
+
+ def run():
+ sys.modules.pop("typing_extensions", None)
+ from typing_extensions import Concatenate
+ return isinstance(Concatenate[...], typing._GenericAlias)
+ isinstance_result_1 = run()
+ sys.setprofile(trace_call)
+ isinstance_result_2 = run()
+ sys.stdout.write(f"{isinstance_result_1} {isinstance_result_2}")
+ """
+ )
+
+ # Run this in an isolated process or it pollutes the environment
+ # and makes other tests fail:
+ try:
+ proc = subprocess.run(
+ [sys.executable, "-c", code], check=True, capture_output=True, text=True,
+ )
+ except subprocess.CalledProcessError as exc:
+ print("stdout", exc.stdout, sep="\n")
+ print("stderr", exc.stderr, sep="\n")
+ raise
+
+ # Sanity checks that assert the test is working as expected
+ self.assertIsInstance(proc.stdout, str)
+ result1, result2 = proc.stdout.split(" ")
+ self.assertIn(result1, {"True", "False"})
+ self.assertIn(result2, {"True", "False"})
+
+ # The actual test:
+ self.assertEqual(result1, result2)
+
 class TypeGuardTests(BaseTestCase):
  def test_basics(self):
  TypeGuard[int] # OK
@@ -6652,6 +6693,46 @@ def test_type_var_inheritance(self):
  self.assertFalse(isinstance(Unpack[Ts], TypeVar))
  self.assertFalse(isinstance(Unpack[Ts], typing.TypeVar))
 
+ def test_isinstance_results_unaffected_by_presence_of_tracing_function(self):
+ # See https://github.com/python/typing_extensions/issues/661
+
+ code = textwrap.dedent(
+ """\
+ import sys, typing
+
+ def trace_call(*args):
+ return trace_call
+
+ def run():
+ sys.modules.pop("typing_extensions", None)
+ from typing_extensions import TypeVarTuple, Unpack
+ return isinstance(Unpack[TypeVarTuple("Ts")], typing.TypeVar)
+ isinstance_result_1 = run()
+ sys.setprofile(trace_call)
+ isinstance_result_2 = run()
+ sys.stdout.write(f"{isinstance_result_1} {isinstance_result_2}")
+ """
+ )
+
+ # Run this in an isolated process or it pollutes the environment
+ # and makes other tests fail:
+ try:
+ proc = subprocess.run(
+ [sys.executable, "-c", code], check=True, capture_output=True, text=True,
+ )
+ except subprocess.CalledProcessError as exc:
+ print("stdout", exc.stdout, sep="\n")
+ print("stderr", exc.stderr, sep="\n")
+ raise
+
+ # Sanity checks that assert the test is working as expected
+ self.assertIsInstance(proc.stdout, str)
+ result1, result2 = proc.stdout.split(" ")
+ self.assertIn(result1, {"True", "False"})
+ self.assertIn(result2, {"True", "False"})
+
+ # The actual test:
+ self.assertEqual(result1, result2)
 
 class TypeVarTupleTests(BaseTestCase):
 

src/typing_extensions.py

@@ -1986,7 +1986,9 @@ class _ConcatenateGenericAlias(list):
  __class__ = typing._GenericAlias
 
  def __init__(self, origin, args):
- super().__init__(args)
+ # Cannot use `super().__init__` here because of the `__class__` assignment
+ # in the class body (https://github.com/python/typing_extensions/issues/661)
+ list.__init__(self, args)
  self.__origin__ = origin
  self.__args__ = args
 
@@ -2545,7 +2547,10 @@ def __typing_is_unpacked_typevartuple__(self):
  def __getitem__(self, args):
  if self.__typing_is_unpacked_typevartuple__:
  return args
- return super().__getitem__(args)
+ # Cannot use `super().__getitem__` here because of the `__class__` assignment
+ # in the class body on Python <=3.11
+ # (https://github.com/python/typing_extensions/issues/661)
+ return typing._GenericAlias.__getitem__(self, args)
 
  @_UnpackSpecialForm
  def Unpack(self, parameters):