Load custom plugins when linting in parallel (#8683)

2 files changed, 11 insertions, 3 deletions

diff --git a/pylint/lint/parallel.py b/pylint/lint/parallel.py
index e57c7e8ab..72f770043 100644
--- a/pylint/lint/parallel.py
+++ b/pylint/lint/parallel.py
@@ -52,6 +52,11 @@ def _worker_initialize(
     _worker_linter.set_reporter(reporters.CollectingReporter())
     _worker_linter.open()
 
+    # Re-register dynamic plugins, since the pool does not have access to the
+    # astroid module that existed when the linter was pickled.
+    _worker_linter.load_plugin_modules(_worker_linter._dynamic_plugins, force=True)
+    _worker_linter.load_plugin_configuration()
+
     if extra_packages_paths:
         _augment_sys_path(extra_packages_paths)
 
diff --git a/pylint/lint/pylinter.py b/pylint/lint/pylinter.py
index ed607aca5..324c54b1b 100644
--- a/pylint/lint/pylinter.py
+++ b/pylint/lint/pylinter.py
@@ -13,7 +13,7 @@ import sys
 import tokenize
 import traceback
 from collections import defaultdict
-from collections.abc import Callable, Iterator, Sequence
+from collections.abc import Callable, Iterable, Iterator, Sequence
 from io import TextIOWrapper
 from pathlib import Path
 from re import Pattern
@@ -363,15 +363,18 @@ class PyLinter(
         checkers.initialize(self)
         reporters.initialize(self)
 
-    def load_plugin_modules(self, modnames: list[str]) -> None:
+    def load_plugin_modules(self, modnames: Iterable[str], force: bool = False) -> None:
         """Check a list of pylint plugins modules, load and register them.
 
         If a module cannot be loaded, never try to load it again and instead
         store the error message for later use in ``load_plugin_configuration``
         below.
+
+        If `force` is True (useful when multiprocessing), then the plugin is
+        reloaded regardless if an entry exists in self._dynamic_plugins.
         """
         for modname in modnames:
-            if modname in self._dynamic_plugins:
+            if modname in self._dynamic_plugins and not force:
                 continue
             try:
                 module = astroid.modutils.load_module_from_name(modname)