Disable design by default

.gitignore

@@ -25,3 +25,5 @@ debian/pylint
 .eggs/
 .pytest_cache/
 .mypy_cache/
+.vscode
+venv/

doc/faq.rst

@@ -182,9 +182,12 @@ tricks like: ::
 
 pylint does have some messages disabled by default, either because
 they are prone to false positives or that they are opinionated enough
-for not being included as default messages. But most of the disabled
-messages are from the Python 3 porting checker, which is disabled by
-default. It needs special activation with the ``--py3k`` flag.
+for not being included as default messages. The disabled messages are 
+from the Python 3 porting checker and design checker, which are disabled 
+by default. The Python 3 porting checker needs special activation with 
+the ``--py3k`` flag. The design checker can be enabled with
+``--enabled=design``.
+
 
 4.8 I am using another popular linter alongside pylint. Which messages should I disable to avoid duplicates?
 ------------------------------------------------------------------------------------------------------------

doc/whatsnew/2.7.rst

@@ -20,3 +20,5 @@ Other Changes
 * Fix bug that lead to duplicate messages when using ``--jobs 2`` or more.
 
   Close #3584
+
+* The `design` checker has been disabled by default, users can still explicitly enable the checker by specifying ``--enabled=design`` at the command line or including ``enable=design`` under the "MESSAGES CONTROL" section in their config files.

pylint/checkers/design_analysis.py

@@ -160,6 +160,7 @@ class MisdesignChecker(BaseChecker):
     """
 
     __implements__ = (IAstroidChecker,)
+    enabled = False
 
     # configuration section name
     name = "design"

pylint/testutils.py

@@ -504,6 +504,7 @@ def __init__(self, test_file):
         self._linter.set_reporter(_test_reporter)
         self._linter.config.persistent = 0
         checkers.initialize(self._linter)
+        self._linter.enable("design")
         self._linter.disable("I")
         try:
             self._linter.read_config_file(test_file.option_file)

tests/lint/unittest_lint.py

@@ -584,6 +584,15 @@ def test_python3_checker_disabled(linter):
     assert "python3" in checker_names
 
 
+def test_design_checker_disabled(linter):
+    checker_names = [c.name for c in linter.prepare_checkers()]
+    assert "design" not in checker_names
+
+    linter.set_option("enable", "design")
+    checker_names = [c.name for c in linter.prepare_checkers()]
+    assert "design" in checker_names
+
+
 def test_full_documentation(linter):
     out = StringIO()
     linter.print_full_documentation(out)

tests/test_func.py

@@ -71,6 +71,7 @@ def _check_result(self, got):
         assert self._get_expected().strip() + "\n" == got.strip() + "\n"
 
     def _test(self, tocheck):
+        self.linter.enable("design")
         if INFO_TEST_RGX.match(self.module):
             self.linter.enable("I")
         else: