Revert exposing a function that directly manipulates the exception state

This is done as a separate commit to make reviewing the next commit (ie.
the actual implementation) easier. If accepted, this commit should be
squashed.

Author: pR0Ps

Lib/contextlib.py

@@ -20,12 +20,6 @@
            "chdir"]
 
 
-try:
-    from _contextlib import _setup_genmgr_ctx
-except ImportError:
-    _setup_genmgr_ctx = None
-
-
 class AbstractContextManager(abc.ABC):
 
     """An abstract base class for context managers."""
@@ -245,8 +239,6 @@ def __exit__(self, typ, value, traceback):
                 # context to be what it was just before the generator's yield
                 # statement before throwing the current exception into it.
                 # (see gh-111676).
-                if _setup_genmgr_ctx is not None:
-                    _setup_genmgr_ctx(exc_context)
                 self.gen.throw(value)
             except StopIteration as exc:
                 # Suppress StopIteration *unless* it's the same exception that

Lib/test/test_contextlib.py

@@ -1671,138 +1671,5 @@ def test_exception(self):
         self.assertEqual(os.getcwd(), old_cwd)
 
 
-try:
-    from _contextlib import _setup_genmgr_ctx
-except ImportError:
-    _setup_genmgr_ctx = None
-
-if _setup_genmgr_ctx:
-    class SetExceptionTests(unittest.TestCase):
-
-        def tearDown(self):
-            # make sure we don't leave the global exception set
-            _setup_genmgr_ctx(None);
-
-        def test_set_exc_invalid_values(self):
-            for x in (0, "1", b"2"):
-                with self.assertRaises(TypeError):
-                    _setup_genmgr_ctx(x);
-
-        def test_clear_exc(self):
-            try:
-                raise ValueError()
-            except ValueError:
-                self.assertIsInstance(sys.exception(), ValueError)
-                _setup_genmgr_ctx(None)
-                self.assertIsNone(sys.exception())
-
-        def test_set_exc(self):
-            exc = ValueError()
-            self.assertIsNone(sys.exception())
-            _setup_genmgr_ctx(exc)
-            self.assertIs(sys.exception(), exc)
-
-        def test_set_exc_replaced_by_new_exception_and_restored(self):
-            exc = ValueError()
-            _setup_genmgr_ctx(exc)
-            self.assertIs(sys.exception(), exc)
-            try:
-                raise TypeError()
-            except TypeError:
-                self.assertIsInstance(sys.exception(), TypeError)
-                self.assertIs(sys.exception().__context__, exc)
-
-            self.assertIs(sys.exception(), exc)
-
-        def test_set_exc_popped_on_exit_except(self):
-            exc = ValueError()
-            try:
-                raise TypeError()
-            except TypeError:
-                self.assertIsInstance(sys.exception(), TypeError)
-                _setup_genmgr_ctx(exc)
-                self.assertIs(sys.exception(), exc)
-            self.assertIsNone(sys.exception())
-
-        def test_cleared_exc_overridden_and_restored(self):
-            try:
-                raise ValueError()
-            except ValueError:
-                try:
-                    raise TypeError()
-                except TypeError:
-                    self.assertIsInstance(sys.exception(), TypeError)
-                    _setup_genmgr_ctx(None)
-                    self.assertIsNone(sys.exception())
-                    try:
-                        raise IndexError()
-                    except IndexError:
-                        self.assertIsInstance(sys.exception(), IndexError)
-                        self.assertIsNone(sys.exception().__context__)
-                    self.assertIsNone(sys.exception())
-                self.assertIsInstance(sys.exception(), ValueError)
-            self.assertIsNone(sys.exception())
-
-        def test_clear_exc_in_generator(self):
-            def inner():
-                self.assertIsNone(sys.exception())
-                yield
-                self.assertIsInstance(sys.exception(), ValueError)
-                _setup_genmgr_ctx(None)
-                self.assertIsNone(sys.exception())
-                yield
-                self.assertIsNone(sys.exception())
-
-            # with a single exception in exc_info stack
-            g = inner()
-            next(g)
-            try:
-                raise ValueError()
-            except:
-                self.assertIsInstance(sys.exception(), ValueError)
-                next(g)
-                self.assertIsInstance(sys.exception(), ValueError)
-            self.assertIsNone(sys.exception())
-            with self.assertRaises(StopIteration):
-                next(g)
-            self.assertIsNone(sys.exception())
-
-            # with multiple exceptions in exc_info stack by chaining generators
-            def outer():
-                g = inner()
-                self.assertIsNone(sys.exception())
-                yield next(g)
-                self.assertIsInstance(sys.exception(), TypeError)
-                try:
-                    raise ValueError()
-                except:
-                    self.assertIsInstance(sys.exception(), ValueError)
-                    self.assertIsInstance(sys.exception().__context__, TypeError)
-                    yield next(g)
-                    # at this point the TypeError from the caller has been handled
-                    # by the caller's except block. Even still, it should still be
-                    # referenced as the __context__ of the current exception.
-                    self.assertIsInstance(sys.exception(), ValueError)
-                    self.assertIsInstance(sys.exception().__context__, TypeError)
-                # not handling an exception, caller isn't handling one either
-                self.assertIsNone(sys.exception())
-                with self.assertRaises(StopIteration):
-                    next(g)
-                self.assertIsNone(sys.exception())
-
-            g = outer()
-            next(g)
-            try:
-                raise TypeError()
-            except:
-                self.assertIsInstance(sys.exception(), TypeError)
-                next(g)
-                self.assertIsInstance(sys.exception(), TypeError)
-            self.assertIsNone(sys.exception())
-            with self.assertRaises(StopIteration):
-                next(g)
-            self.assertIsNone(sys.exception())
-
-
 if __name__ == "__main__":
     unittest.main()

Modules/Setup.bootstrap.in

@@ -31,7 +31,6 @@ _weakref _weakref.c
 
 # commonly used core modules
 _abc _abc.c
-_contextlib _contextlibmodule.c
 _functools _functoolsmodule.c
 _locale _localemodule.c
 _opcode _opcode.c

Modules/_contextlibmodule.c

@@ -444,7 +444,6 @@
     </ClCompile>
     <ClCompile Include="..\Modules\_codecsmodule.c" />
     <ClCompile Include="..\Modules\_collectionsmodule.c" />
-    <ClCompile Include="..\Modules\_contextlibmodule.c" />
     <ClCompile Include="..\Modules\_csv.c" />
     <ClCompile Include="..\Modules\_functoolsmodule.c" />
     <ClCompile Include="..\Modules\_hacl\Hacl_Hash_MD5.c" />