Support -va as well as -av

docs/changelog/2343.bugfix.rst

@@ -0,0 +1 @@
+Fix CLI raises an error for ``-va`` with ``ignored explicit argument 'a'`` - by :user:`gaborbernat`.

src/tox/config/cli/parse.py

@@ -43,7 +43,11 @@ def get_options(*args: str) -> Options:
 def _get_base(args: Sequence[str]) -> tuple[int, ToxHandler, Source]:
     """First just load the base options (verbosity+color) to setup the logging framework."""
     tox_parser = ToxParser.base()
-    parsed, _ = tox_parser.parse_known_args(args)
+    parsed = Parsed()
+    try:
+        tox_parser.parse_known_args(args, namespace=parsed)
+    except SystemExit:
+        ...  # ignore parse errors, such as -va raises ignored explicit argument 'a'
     guess_verbosity = parsed.verbosity
     handler = setup_report(guess_verbosity, parsed.is_colored)
     from tox.plugin.manager import MANAGER  # load the plugin system right after we set up report

tests/config/cli/test_parse.py

@@ -38,3 +38,9 @@ def test_verbosity_guess_miss_match(capsys: CaptureFixture) -> None:
 
     out, err = capsys.readouterr()
     assert out == "ROOT: E\nROOT: W\nROOT: I\n"
+
+
+@pytest.mark.parametrize("arg", ["-av", "-va"])
+def test_verbosity(arg: str) -> None:
+    result = get_options(arg)
+    assert result.parsed.verbosity == 3