Make all exceptions pickleable

CHANGELOG.md

@@ -6,6 +6,7 @@ Find out more about isort's release policy [here](https://pycqa.github.io/isort/
 
 ### 5.9.3 TBD
   - Improved text of skipped file message to mention gitignore feature.
+  - Made all exceptions pickleable.
   - Fixed #1779: Pylama integration ignores pylama specific isort config overrides.
   - Fixed #1781: `--from-first` CLI flag shouldn't take any arguments.
   - Fixed #1785: `_ast` module incorrectly excluded from stdlib definition.

isort/exceptions.py

@@ -1,4 +1,5 @@
 """All isort specific exception classes should be defined here"""
+from functools import partial
 from pathlib import Path
 from typing import Any, Dict, List, Type, Union
 
@@ -8,6 +9,9 @@
 class ISortError(Exception):
     """Base isort exception object from which all isort sourced exceptions should inherit"""
 
+    def __reduce__(self):  # type: ignore
+        return (partial(type(self), **self.__dict__), ())
+
 
 class InvalidSettingsPath(ISortError):
     """Raised when a settings path is provided that is neither a valid file or directory"""
@@ -48,13 +52,14 @@ class FileSkipped(ISortError):
 
     def __init__(self, message: str, file_path: str):
         super().__init__(message)
+        self.message = message
         self.file_path = file_path
 
 
 class FileSkipComment(FileSkipped):
     """Raised when an entire file is skipped due to a isort skip file comment"""
 
-    def __init__(self, file_path: str):
+    def __init__(self, file_path: str, **kwargs: str):
         super().__init__(
             f"{file_path} contains a file skip comment and was skipped.", file_path=file_path
         )
@@ -63,7 +68,7 @@ def __init__(self, file_path: str):
 class FileSkipSetting(FileSkipped):
     """Raised when an entire file is skipped due to provided isort settings"""
 
-    def __init__(self, file_path: str):
+    def __init__(self, file_path: str, **kwargs: str):
         super().__init__(
             f"{file_path} was skipped as it's listed in 'skip' setting"
             " or matches a glob in 'skip_glob' setting",

tests/unit/test_exceptions.py

@@ -1,3 +1,5 @@
+import pickle
+
 from isort import exceptions
 
 
@@ -8,6 +10,9 @@ def setup_class(self):
     def test_init(self):
         assert isinstance(self.instance, exceptions.ISortError)
 
+    def test_pickleable(self):
+        assert isinstance(pickle.loads(pickle.dumps(self.instance)), exceptions.ISortError)
+
 
 class TestExistingSyntaxErrors(TestISortError):
     def setup_class(self):