Remove deprecated `pytest.warns(None)`

doc/en/deprecations.rst

@@ -374,18 +374,6 @@ Users expected in this case that the ``usefixtures`` mark would have its intende
 Now pytest will issue a warning when it encounters this problem, and will raise an error in the future versions.
 
 
-Using ``pytest.warns(None)``
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-.. deprecated:: 7.0
-
-:func:`pytest.warns(None) <pytest.warns>` is now deprecated because it was frequently misused.
-Its correct usage was checking that the code emits at least one warning of any type - like ``pytest.warns()``
-or ``pytest.warns(Warning)``.
-
-See :ref:`warns use cases` for examples.
-
-
 Returning non-None value in test functions
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
@@ -445,6 +433,19 @@ an appropriate period of deprecation has passed.
 Some breaking changes which could not be deprecated are also listed.
 
 
+Using ``pytest.warns(None)``
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. deprecated:: 7.0
+.. versionremoved:: 8.0
+
+:func:`pytest.warns(None) <pytest.warns>` is now deprecated because it was frequently misused.
+Its correct usage was checking that the code emits at least one warning of any type - like ``pytest.warns()``
+or ``pytest.warns(Warning)``.
+
+See :ref:`warns use cases` for examples.
+
+
 Backward compatibilities in ``Parser.addoption``
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 

src/_pytest/deprecated.py

@@ -65,13 +65,6 @@ NODE_CTOR_FSPATH_ARG = UnformattedWarning(
     "#fspath-argument-for-node-constructors-replaced-with-pathlib-path",
 )
 
-WARNS_NONE_ARG = PytestRemovedIn8Warning(
-    "Passing None has been deprecated.\n"
-    "See https://docs.pytest.org/en/latest/how-to/capture-warnings.html"
-    "#additional-use-cases-of-warnings-in-tests"
-    " for alternatives in common use cases."
-)
-
 KEYWORD_MSG_ARG = UnformattedWarning(
     PytestRemovedIn8Warning,
     "pytest.{func}(msg=...) is now deprecated, use pytest.{func}(reason=...) instead",

src/_pytest/recwarn.py

@@ -18,7 +18,6 @@ from typing import TypeVar
 from typing import Union
 
 from _pytest.deprecated import check_ispytest
-from _pytest.deprecated import WARNS_NONE_ARG
 from _pytest.fixtures import fixture
 from _pytest.outcomes import fail
 
@@ -264,9 +263,7 @@ class WarningsRecorder(warnings.catch_warnings):  # type:ignore[type-arg]
 class WarningsChecker(WarningsRecorder):
     def __init__(
         self,
-        expected_warning: Optional[
+        expected_warning: Union[Type[Warning], Tuple[Type[Warning], ...]] = Warning,
-            Union[Type[Warning], Tuple[Type[Warning], ...]]
-        ] = Warning,
         match_expr: Optional[Union[str, Pattern[str]]] = None,
         *,
         _ispytest: bool = False,
@@ -275,15 +272,14 @@ class WarningsChecker(WarningsRecorder):
         super().__init__(_ispytest=True)
 
         msg = "exceptions must be derived from Warning, not %s"
-        if expected_warning is None:
+        if isinstance(expected_warning, tuple):
-            warnings.warn(WARNS_NONE_ARG, stacklevel=4)
-            expected_warning_tup = None
-        elif isinstance(expected_warning, tuple):
             for exc in expected_warning:
                 if not issubclass(exc, Warning):
                     raise TypeError(msg % type(exc))
             expected_warning_tup = expected_warning
-        elif issubclass(expected_warning, Warning):
+        elif isinstance(expected_warning, type) and issubclass(
+            expected_warning, Warning
+        ):
             expected_warning_tup = (expected_warning,)
         else:
             raise TypeError(msg % type(expected_warning))
@@ -307,10 +303,6 @@ class WarningsChecker(WarningsRecorder):
 
         __tracebackhide__ = True
 
-        if self.expected_warning is None:
-            # nothing to do in this deprecated case, see WARNS_NONE_ARG above
-            return
-
         def found_str():
             return pformat([record.message for record in self], indent=2)
 

testing/deprecated_test.py

@@ -120,20 +120,6 @@ def test_hookproxy_warnings_for_pathlib(tmp_path, hooktype, request):
             )
 
 
-def test_warns_none_is_deprecated():
-    with pytest.warns(
-        PytestDeprecationWarning,
-        match=re.escape(
-            "Passing None has been deprecated.\n"
-            "See https://docs.pytest.org/en/latest/how-to/capture-warnings.html"
-            "#additional-use-cases-of-warnings-in-tests"
-            " for alternatives in common use cases."
-        ),
-    ):
-        with pytest.warns(None):  # type: ignore[call-overload]
-            pass
-
-
 class TestSkipMsgArgumentDeprecated:
     def test_skip_with_msg_is_deprecated(self, pytester: Pytester) -> None:
         p = pytester.makepyfile(

testing/test_recwarn.py

@@ -345,17 +345,9 @@ class TestWarns:
         assert str(record[0].message) == "user"
         assert str(record[1].message) == "runtime"
 
-    def test_record_only_none_deprecated_warn(self) -> None:
+    def test_record_only_none_type_error(self) -> None:
-        # This should become an error when WARNS_NONE_ARG is removed in Pytest 8.0
+        with pytest.raises(TypeError):
-        with warnings.catch_warnings():
+            pytest.warns(None)  # type: ignore[call-overload]
-            warnings.simplefilter("ignore")
-            with pytest.warns(None) as record:  # type: ignore[call-overload]
-                warnings.warn("user", UserWarning)
-                warnings.warn("runtime", RuntimeWarning)
-
-            assert len(record) == 2
-            assert str(record[0].message) == "user"
-            assert str(record[1].message) == "runtime"
 
     def test_record_by_subclass(self) -> None:
         with pytest.warns(Warning) as record:

testing/test_tmpdir.py

@@ -530,13 +530,11 @@ class TestRmRf:
             assert fn.is_file()
 
         # ignored function
-        with warnings.catch_warnings():
+        with warnings.catch_warnings(record=True) as w:
-            warnings.simplefilter("ignore")
-            with pytest.warns(None) as warninfo:  # type: ignore[call-overload]
             exc_info4 = PermissionError()
             on_rm_rf_error(os.open, str(fn), exc_info4, start_path=tmp_path)
             assert fn.is_file()
-            assert not [x.message for x in warninfo]
+            assert not [x.message for x in w]
 
         exc_info5 = PermissionError()
         on_rm_rf_error(os.unlink, str(fn), exc_info5, start_path=tmp_path)