[deprecation] Make 'OutputLine' require a fixed number of args

Co-authored-by: Daniël van Noord <13665637+DanielNoord@users.noreply.github.com>

doc/whatsnew/fragments/8474.internal

@@ -0,0 +1,5 @@
+Following a deprecation period, the ``OutputLine`` class now requires
+the right number of argument all the time. The functional output can be
+regenerated automatically to achieve that easily.
+
+Refs #8474

pylint/testutils/output_line.py

@@ -4,7 +4,6 @@
 
 from __future__ import annotations
 
-import warnings
 from collections.abc import Sequence
 from typing import Any, NamedTuple, TypeVar
 
@@ -89,63 +88,22 @@ def from_csv(
         """
         if isinstance(row, str):
             row = row.split(",")
-        # noinspection PyBroadException
-        # pylint: disable = too-many-try-statements
         try:
+            line = int(row[1])
             column = cls._get_column(row[2])
-            if len(row) == 5:
-                # TODO: 3.0
-                warnings.warn(
-                    "In pylint 3.0 functional tests expected output should always include the "
-                    "expected confidence level, expected end_line and expected end_column. "
-                    "An OutputLine should thus have a length of 8.",
-                    DeprecationWarning,
-                    stacklevel=2,
-                )
-                return cls(
-                    row[0],
-                    int(row[1]),
-                    column,
-                    None,
-                    None,
-                    row[3],
-                    row[4],
-                    UNDEFINED.name,
-                )
-            if len(row) == 6:
-                # TODO: 3.0
-                warnings.warn(
-                    "In pylint 3.0 functional tests expected output should always include the "
-                    "expected end_line and expected end_column. An OutputLine should thus have "
-                    "a length of 8.",
-                    DeprecationWarning,
-                    stacklevel=2,
-                )
-                return cls(
-                    row[0], int(row[1]), column, None, None, row[3], row[4], row[5]
-                )
-            if len(row) == 8:
-                end_line = cls._get_py38_none_value(row[3], check_endline)
-                end_column = cls._get_py38_none_value(row[4], check_endline)
-                return cls(
-                    row[0],
-                    int(row[1]),
-                    column,
-                    cls._value_to_optional_int(end_line),
-                    cls._value_to_optional_int(end_column),
-                    row[5],
-                    row[6],
-                    row[7],
-                )
-            raise IndexError
-        except Exception:  # pylint: disable=broad-except
-            warnings.warn(
-                "Expected 'msg-symbolic-name:42:27:MyClass.my_function:The message:"
-                f"CONFIDENCE' but we got '{':'.join(row)}'. Try updating the expected"
-                f" output with:\npython tests/test_functional.py {UPDATE_OPTION}",
-                UserWarning,
-                stacklevel=2,
+            end_line = cls._value_to_optional_int(
+                cls._get_py38_none_value(row[3], check_endline)
+            )
+            end_column = cls._value_to_optional_int(
+                cls._get_py38_none_value(row[4], check_endline)
             )
+            # symbol, line, column, end_line, end_column, node, msg, confidences
+            assert len(row) == 8
+            return cls(
+                row[0], line, column, end_line, end_column, row[5], row[6], row[7]
+            )
+        except Exception:  # pylint: disable=broad-except
+            # We need this to not fail for the update script to work.
             return cls("", 0, 0, None, None, "", "", "")
 
     def to_csv(self) -> tuple[str, str, str, str, str, str, str, str]:

tests/testutils/test_output_line.py

@@ -133,83 +133,11 @@ def test_output_line_to_csv(confidence: Confidence, message: _MessageCallable) -
         confidence.name,
     )
 
-
-def test_output_line_from_csv_error() -> None:
-    """Test that errors are correctly raised for incorrect OutputLine's."""
-    # Test a csv-string which does not have a number for line and column
-    with pytest.warns(
-        UserWarning,
-        match="msg-symbolic-name:42:27:MyClass.my_function:The message",
-    ):
-        OutputLine.from_csv("'missing-docstring', 'line', 'column', 'obj', 'msg'", True)
-    # Test a tuple which does not have a number for line and column
-    with pytest.warns(
-        UserWarning, match="we got 'missing-docstring:line:column:obj:msg'"
-    ):
-        csv = ("missing-docstring", "line", "column", "obj", "msg")
-        OutputLine.from_csv(csv, True)
-    # Test a csv-string that is too long
-    with pytest.warns(
-        UserWarning,
-        match="msg-symbolic-name:42:27:MyClass.my_function:The message",
-    ):
-        OutputLine.from_csv(
-            "'missing-docstring', 1, 2, 'obj', 'msg', 'func', 'message', 'conf', 'too_long'",
-            True,
-        )
-
-
-@pytest.mark.parametrize(
-    "confidence,expected_confidence", [[None, "UNDEFINED"], ["INFERENCE", "INFERENCE"]]
-)
-def test_output_line_from_csv_deprecated(
-    confidence: str | None, expected_confidence: str
-) -> None:
-    """Test that the OutputLine NamedTuple is instantiated correctly with from_csv.
-    Test OutputLine's of length 5 or 6.
-    """
-    if confidence:
-        proper_csv = [
-            "missing-docstring",
-            "1",
-            "2",
-            "obj",
-            "msg",
-            confidence,
-        ]
-    else:
-        proper_csv = ["missing-docstring", "1", "2", "obj", "msg"]
-    with pytest.warns(DeprecationWarning) as records:
-        output_line = OutputLine.from_csv(proper_csv, True)
-        assert len(records) == 1
-
-    expected_column = 2 if PY38_PLUS else 0
-    assert output_line == OutputLine(
-        symbol="missing-docstring",
-        lineno=1,
-        column=expected_column,
-        end_lineno=None,
-        end_column=None,
-        object="obj",
-        msg="msg",
-        confidence=expected_confidence,
-    )
-
-
 def test_output_line_from_csv() -> None:
     """Test that the OutputLine NamedTuple is instantiated correctly with from_csv.
     Test OutputLine of length 8.
     """
-    proper_csv = [
-        "missing-docstring",
-        "1",
-        "2",
-        "1",
-        "None",
-        "obj",
-        "msg",
-        "HIGH",
-    ]
+    proper_csv = ["missing-docstring", "1", "2", "1", "None", "obj", "msg", "HIGH"]
     expected_column = 2 if PY38_PLUS else 0
 
     output_line = OutputLine.from_csv(proper_csv)