Remove PY_COLORS, fix spelling and don't modify in place

Author: DanielNoord

custom_dict.txt

@@ -108,6 +108,7 @@ encodings
 endswith
 enum
 enums
+env
 epilog
 epylint
 epytext

doc/user_guide/usage/output.rst

@@ -27,12 +27,12 @@ The colorization of the output can also be controlled through environment
 variables. The precedence for determining output format is as follows:
 
 1. ``NO_COLOR``
-2. ``FORCE_COLOR``, or ``PY_COLORS``
+2. ``FORCE_COLOR``
 3. ``--output-format=...``
 
 Setting ``NO_COLOR`` (to any value) will disable colorized output, while
-``FORCE_COLOR`` or ``PY_COLORS`` (to any value) will enable it, overriding
-the ``--output-format`` option if specified.
+``FORCE_COLOR`` (to any value) will enable it, overriding the
+``--output-format`` option if specified.
 
 
 Custom message formats

doc/whatsnew/fragments/3995.feature

@@ -1,5 +1,6 @@
-Support for ``NO_COLOR`` and ``FORCE_COLOR`` (and ``PY_COLORS``, as an alias to ``FORCE_COLOR``) environment variables has been added.
-When running `pylint`, the reporter that reports to ``stdout`` will be modified according to the requested mode.
-The order is: ``NO_COLOR`` > ``FORCE_COLOR``, ``PY_COLORS`` > ``--output=...``.
+Support for ``NO_COLOR`` and ``FORCE_COLOR`` environment variables has been added.
+When running `pylint`, the reporter that reports to ``stdout`` will be modified according
+to the requested mode.
+The order is: ``NO_COLOR`` > ``FORCE_COLOR`` > ``--output=...``.
 
 Closes #3995 (https://github.com/pylint-dev/pylint/issues/3995).

pylint/lint/pylinter.py

@@ -74,7 +74,6 @@
 
 NO_COLOR = "NO_COLOR"
 FORCE_COLOR = "FORCE_COLOR"
-PY_COLORS = "PY_COLORS"
 
 WARN_FORCE_COLOR_SET = "FORCE_COLOR is set; ignoring `text` at stdout"
 WARN_NO_COLOR_SET = "NO_COLOR is set; ignoring `colorized` at stdout"
@@ -261,10 +260,9 @@ def _load_reporter_by_class(reporter_class: str) -> type[BaseReporter]:
 }
 
 
-def _handle_force_color_no_color(reporter: list[reporters.BaseReporter]) -> None:
+def _handle_force_color_no_color(reporters: list[reporters.BaseReporter]) -> list[reporters.BaseReporter]:
     """
-    Check ``NO_COLOR``, ``FORCE_COLOR``, ``PY_COLOR`` and modify the reporter list
-    accordingly.
+    Check ``NO_COLOR`` and ``FORCE_COLOR``, and return the modified reporter list accordingly.
 
     Rules are presented in this table:
     +--------------+---------------+-----------------+------------------------------------------------------------+
@@ -281,9 +279,7 @@ def _handle_force_color_no_color(reporter: list[reporters.BaseReporter]) -> None
     +--------------+---------------+-----------------+------------------------------------------------------------+
     """
     no_color = _is_env_set_and_non_empty(NO_COLOR)
-    force_color = _is_env_set_and_non_empty(FORCE_COLOR) or _is_env_set_and_non_empty(
-        PY_COLORS
-    )
+    force_color = _is_env_set_and_non_empty(FORCE_COLOR)
 
     if no_color and force_color:
         warnings.warn(
@@ -293,34 +289,31 @@ def _handle_force_color_no_color(reporter: list[reporters.BaseReporter]) -> None
         )
         force_color = False
 
-    if no_color:
-        for idx, rep in enumerate(list(reporter)):
-            if not isinstance(rep, ColorizedTextReporter):
-                continue
-
-            if rep.out.buffer is sys.stdout.buffer:
-                warnings.warn(
-                    WARN_NO_COLOR_SET,
-                    ReporterWarning,
-                    stacklevel=2,
-                )
-                reporter.pop(idx)
-                reporter.append(TextReporter())
-
-    elif force_color:
-        for idx, rep in enumerate(list(reporter)):
-            # pylint: disable=unidiomatic-typecheck # Want explicit type check
-            if type(rep) is not TextReporter:
-                continue
+    final_reporters: list[reporters.BaseReporter] = []
+    
+    for idx, rep in enumerate(reporters):
+        if no_color and isinstance(rep, ColorizedTextReporter) and rep.out.buffer is sys.stdout.buffer:
+            warnings.warn(
+                WARN_NO_COLOR_SET,
+                ReporterWarning,
+                stacklevel=2,
+            )
+            final_reporters.append(TextReporter())
+
+   
+        # pylint: disable=unidiomatic-typecheck # Want explicit type check
+        elif force_color and type(rep) is TextReporter and rep.out.buffer is sys.stdout.buffer:
+            warnings.warn(
+                WARN_FORCE_COLOR_SET,
+                ReporterWarning,
+                stacklevel=2,
+            )
+            final_reporters.append(ColorizedTextReporter())
 
-            if rep.out.buffer is sys.stdout.buffer:
-                warnings.warn(
-                    WARN_FORCE_COLOR_SET,
-                    ReporterWarning,
-                    stacklevel=2,
-                )
-                reporter.pop(idx)
-                reporter.append(ColorizedTextReporter())
+        else:
+            final_reporters.append(rep)
+    
+    return final_reporters
 
 
 # pylint: disable=too-many-instance-attributes,too-many-public-methods
@@ -508,7 +501,7 @@ def _load_reporters(self, reporter_names: str) -> None:
             # Extend the lifetime of all opened output files
             close_output_files = stack.pop_all().close
 
-        _handle_force_color_no_color(sub_reporters)
+        sub_reporters = _handle_force_color_no_color(sub_reporters)
 
         if len(sub_reporters) > 1 or output_files:
             self.set_reporter(

tests/lint/test_pylinter.py

@@ -20,7 +20,6 @@
     FORCE_COLOR,
     MANAGER,
     NO_COLOR,
-    PY_COLORS,
     WARN_BOTH_COLOR_SET,
     PyLinter,
     _handle_force_color_no_color,
@@ -139,11 +138,6 @@ def pytest_generate_tests(metafunc: pytest.Metafunc) -> None:
     [True, False],
     ids=lambda no_color: f"{no_color=}",
 )
-@pytest.mark.parametrize(
-    "py_colors",
-    [True, False],
-    ids=lambda py_colors: f"{py_colors=}",
-)
 @pytest.mark.parametrize(
     "force_color",
     [True, False],
@@ -153,16 +147,12 @@ def test_handle_force_color_no_color(
     monkeypatch: pytest.MonkeyPatch,
     recwarn: pytest.WarningsRecorder,
     no_color: bool,
-    py_colors: bool,
     force_color: bool,
     text_reporters: tuple[str],
     colorized_reporters: tuple[str],
 ) -> None:
     monkeypatch.setenv(NO_COLOR, "1" if no_color else "")
     monkeypatch.setenv(FORCE_COLOR, "1" if force_color else "")
-    monkeypatch.setenv(PY_COLORS, "1" if py_colors else "")
-
-    force_color = force_color or py_colors
 
     if STDOUT_TEXT in text_reporters or STDOUT_TEXT in colorized_reporters:
         monkeypatch.setattr(sys, STDOUT_TEXT, io.TextIOWrapper(io.BytesIO()))

tests/lint/test_utils.py

@@ -70,22 +70,17 @@ def test_issue_template_on_fatal_errors(capsys: pytest.CaptureFixture) -> None:
         ("", False),
         (0, True),
         (1, True),
-        (2, True),
         (False, True),
-        ("no", True),
-        ("off", True),
         ("on", True),
-        (True, True),
-        ("yes", True),
     ],
     ids=repr,
 )
 def test_is_env_set_and_non_empty(
-    monkeypatch: pytest.MonkeyPatch, value: Any, expected: bool
+    monkeypatch: pytest.MonkeyPatch, value: object, expected: bool
 ) -> None:
     """Test the function returns True if the environment variable is set and non-empty."""
     env_var = "TEST_VAR"
     if value is not None:
         monkeypatch.setenv(env_var, str(value))
 
-    assert _is_env_set_and_non_empty(env_var) == expected
+    assert _is_env_set_and_non_empty(env_var) is expected