config/argparsing: use our own get_terminal_width()

src/_pytest/_io/__init__.py

@@ -1,6 +1,8 @@
+from .terminalwriter import get_terminal_width
 from .terminalwriter import TerminalWriter
 
 
 __all__ = [
     "TerminalWriter",
+    "get_terminal_width",
 ]

src/_pytest/config/argparsing.py

@@ -15,6 +15,7 @@ from typing import Union
 
 import py
 
+import _pytest._io
 from _pytest.compat import TYPE_CHECKING
 from _pytest.config.exceptions import UsageError
 
@@ -466,7 +467,7 @@ class DropShorterLongHelpFormatter(argparse.HelpFormatter):
     def __init__(self, *args: Any, **kwargs: Any) -> None:
         """Use more accurate terminal width via pylib."""
         if "width" not in kwargs:
-            kwargs["width"] = py.io.get_terminal_width()
+            kwargs["width"] = _pytest._io.get_terminal_width()
         super().__init__(*args, **kwargs)
 
     def _format_action_invocation(self, action: argparse.Action) -> str:

testing/test_config.py

@@ -1253,7 +1253,7 @@ def test_help_formatter_uses_py_get_terminal_width(monkeypatch):
     formatter = DropShorterLongHelpFormatter("prog")
     assert formatter._width == 90
 
-    monkeypatch.setattr("py.io.get_terminal_width", lambda: 160)
+    monkeypatch.setattr("_pytest._io.get_terminal_width", lambda: 160)
     formatter = DropShorterLongHelpFormatter("prog")
     assert formatter._width == 160