Change PytestRemovedIn7Warning to error by default

Per our backward compatibility policy.

Co-authored-by: Bruno Oliveira <nicoddemus@gmail.com>

changelog/9308.breaking.rst

@@ -0,0 +1,22 @@
+**PytestRemovedIn7Warning deprecation warnings are now errors by default.**
+
+Following our plan to remove deprecated features with as little disruption as
+possible, all warnings of type ``PytestRemovedIn7Warning `` now generate errors
+instead of warning messages by default.
+
+**The affected features will be effectively removed in pytest 7.1**, so please consult the
+:ref:`deprecations` section in the docs for directions on how to update existing code.
+
+In the pytest ``7.0.X`` series, it is possible to change the errors back into warnings as a
+stopgap measure by adding this to your ``pytest.ini`` file:
+
+.. code-block:: ini
+
+    [pytest]
+    filterwarnings =
+        ignore::pytest.PytestRemovedIn7Warning
+
+But this will stop working when pytest ``7.1`` is released.
+
+**If you have concerns** about the removal of a specific feature, please add a
+comment to :issue:`9308`.

src/_pytest/warnings.py

@@ -49,6 +49,8 @@ def catch_warnings_for_item(
             warnings.filterwarnings("always", category=DeprecationWarning)
             warnings.filterwarnings("always", category=PendingDeprecationWarning)
 
+        warnings.filterwarnings("error", category=pytest.PytestRemovedIn7Warning)
+
         apply_warning_filters(config_filters, cmdline_filters)
 
         # apply filters from "filterwarnings" marks

testing/test_mark.py

@@ -831,7 +831,9 @@ class TestKeywordSelection:
             def test_three(): assert 1
         """
         )
-        reprec = pytester.inline_run("-k", "test_two:", threepass)
+        reprec = pytester.inline_run(
+            "-Wignore::pytest.PytestRemovedIn7Warning", "-k", "test_two:", threepass
+        )
         passed, skipped, failed = reprec.listoutcomes()
         assert len(passed) == 2
         assert not failed

testing/test_terminal.py

@@ -682,7 +682,9 @@ class TestTerminalFunctional:
                     pass
            """
         )
-        result = pytester.runpytest("-k", "test_two:", testpath)
+        result = pytester.runpytest(
+            "-Wignore::pytest.PytestRemovedIn7Warning", "-k", "test_two:", testpath
+        )
         result.stdout.fnmatch_lines(
             ["collected 3 items / 1 deselected / 2 selected", "*test_deselected.py ..*"]
         )

testing/test_warnings.py

@@ -518,11 +518,8 @@ class TestDeprecationWarningsByDefault:
 
 
 @pytest.mark.parametrize("change_default", [None, "ini", "cmdline"])
-@pytest.mark.skip(
-    reason="This test should be enabled again before pytest 7.0 is released"
-)
-def test_deprecation_warning_as_error(pytester: Pytester, change_default) -> None:
-    """This ensures that PytestDeprecationWarnings raised by pytest are turned into errors.
+def test_removed_in_x_warning_as_error(pytester: Pytester, change_default) -> None:
+    """This ensures that PytestRemovedInXWarnings raised by pytest are turned into errors.
 
     This test should be enabled as part of each major release, and skipped again afterwards
     to ensure our deprecations are turning into warnings as expected.
@@ -531,7 +528,7 @@ def test_deprecation_warning_as_error(pytester: Pytester, change_default) -> Non
         """
         import warnings, pytest
         def test():
-            warnings.warn(pytest.PytestDeprecationWarning("some warning"))
+            warnings.warn(pytest.PytestRemovedIn7Warning("some warning"))
     """
     )
     if change_default == "ini":
@@ -539,12 +536,12 @@ def test_deprecation_warning_as_error(pytester: Pytester, change_default) -> Non
             """
             [pytest]
             filterwarnings =
-                ignore::pytest.PytestDeprecationWarning
+                ignore::pytest.PytestRemovedIn7Warning
         """
         )
 
     args = (
-        ("-Wignore::pytest.PytestDeprecationWarning",)
+        ("-Wignore::pytest.PytestRemovedIn7Warning",)
         if change_default == "cmdline"
         else ()
     )