Make sure that --generate-rcfile generates a valid file (#6566)

Author: DanielNoord

pylint/utils/utils.py

@@ -380,6 +380,11 @@ def _ini_format(stream: TextIO, options: list[tuple[str, OptionDict, Any]]) -> N
         DeprecationWarning,
     )
     for optname, optdict, value in options:
+        # Skip deprecated option
+        if "kwargs" in optdict:
+            assert isinstance(optdict["kwargs"], dict)
+            if "new_names" in optdict["kwargs"]:
+                continue
         value = _format_option_value(optdict, value)
         help_opt = optdict.get("help")
         if help_opt:
@@ -389,7 +394,7 @@ def _ini_format(stream: TextIO, options: list[tuple[str, OptionDict, Any]]) -> N
             print(help_opt, file=stream)
         else:
             print(file=stream)
-        if value is None:
+        if value in {"None", "False"}:
             print(f"#{optname}=", file=stream)
         else:
             value = str(value).strip()

tests/test_self.py

@@ -1345,6 +1345,17 @@ def test_generate_rcfile() -> None:
         )
         assert process.stdout == process_two.stdout
 
+        # Check that the generated file is valid
+        with tempfile.NamedTemporaryFile(mode="w", delete=False) as temp:
+            filename = temp.name
+            temp.write(process.stdout)
+            runner = Run(
+                [join(HERE, "regrtest_data", "empty.py"), f"--rcfile={filename}"],
+                exit=False,
+            )
+            assert not runner.linter.msg_status
+        os.remove(filename)
+
     @staticmethod
     def test_generate_config_disable_symbolic_names() -> None:
         """Test that --generate-rcfile puts symbolic names in the --disable option."""