Support both isort 4 and isort 5

.isort.cfg

@@ -4,4 +4,4 @@ line_length=88
 known_third_party=astroid, sphinx, isort, pytest, mccabe, six, toml
 include_trailing_comma=True
 skip_glob=tests/functional/**,tests/input/**,tests/extensions/data/**,tests/regrtest_data/**,tests/data/**,astroid/**,venv/**
-project=pylint
+src_paths=pylint

ChangeLog

@@ -41,6 +41,10 @@ Release date: TBA
 
 * Add `raise-missing-from` check for exceptions that should have a cause.
 
+* Support both isort 4 and isort 5. If you have pinned isort 4 in your projet requirements, nothing changes. If you use isort 5, though, note that the `known-standard-library` option is not interpreted the same in isort 4 and isort 5 (see the migration guide in isort documentation for further details). For compatibility's sake for most pylint users, the `known-standard-library` option in pylint now maps to `extra-standard-library` in isort 5. If you really want what `known-standard-library` now means in isort 5, you must disable the `wrong-import-order` check in pylint and run isort manually with a proper isort configuration file.
+
+  Close #3722
+
 
 What's New in Pylint 2.5.4?
 ===========================

doc/whatsnew/2.6.rst

@@ -27,3 +27,7 @@ Other Changes
 * `mixed-indentation` has been removed, it is no longer useful since TabError is included directly in python3
 
 * Fix superfluous-parens false-positive for the walrus operator
+
+* Add support for both isort 4 and isort 5. If you have pinned isort 4 in your projet requirements, nothing changes. If you use isort 5, though, note that the `known-standard-library` option is not interpreted the same in isort 4 and isort 5 (see `the migration guide in isort documentation`_ for further details). For compatibility's sake for most pylint users, the `known-standard-library` option in pylint now maps to `extra-standard-library` in isort 5. If you really want what `known-standard-library` now means in isort 5, you must disable the `wrong-import-order` check in pylint and run isort manually with a proper isort configuration file.
+
+.. _the migration guide in isort documentation: https://timothycrosley.github.io/isort/docs/upgrade_guides/5.0.0/#known_standard_library

man/pylint.1

@@ -209,7 +209,7 @@ Create a graph of external dependencies in the given file (report RP0402 must no
 .IP "--int-import-graph=<file.dot>"
 Create a graph of internal dependencies in the given file (report RP0402 must not be disabled). [default: none]
 .IP "--known-standard-library=<modules>"
-Force import order to recognize a module as part of the standard compatibility libraries. [default: none]
+Force import order to recognize a module as part of the standard compatibility libraries.
 .IP "--known-third-party=<modules>"
 Force import order to recognize a module as part of a third party library. [default: enchant]
 .IP "--allow-any-import-level=<modules>"

pylint/__pkginfo__.py

@@ -38,7 +38,7 @@
 
 install_requires = [
     "astroid>=2.4.0,<=2.5",
-    "isort>=4.2.5,<5",
+    "isort>=4.2.5,<6",
     "mccabe>=0.6,<0.7",
     "toml>=0.7.1",
 ]

pylint/checkers/base.py

@@ -54,7 +54,6 @@
 # For details: https://github.com/PyCQA/pylint/blob/master/COPYING
 
 """basic checker for Python code"""
-
 import builtins
 import collections
 import itertools
@@ -67,8 +66,8 @@
 import astroid.scoped_nodes
 from astroid.arguments import CallSite
 
-import pylint.utils as lint_utils
 from pylint import checkers, exceptions, interfaces
+from pylint import utils as lint_utils
 from pylint.checkers import utils
 from pylint.checkers.utils import (
     is_overload_stub,

pylint/checkers/imports.py

@@ -46,7 +46,6 @@
 from distutils import sysconfig
 
 import astroid
-import isort
 from astroid import modutils
 from astroid.decorators import cached
 
@@ -60,7 +59,7 @@
 from pylint.graph import DotBackend, get_cycles
 from pylint.interfaces import IAstroidChecker
 from pylint.reporters.ureports.nodes import Paragraph, VerbatimText
-from pylint.utils import get_global_option
+from pylint.utils import IsortDriver, get_global_option
 
 
 def _qualified_names(modname):
@@ -709,11 +708,7 @@ def _check_imports_order(self, _module_node):
         third_party_not_ignored = []
         first_party_not_ignored = []
         local_not_ignored = []
-        isort_obj = isort.SortImports(
-            file_contents="",
-            known_third_party=self.config.known_third_party,
-            known_standard_library=self.config.known_standard_library,
-        )
+        isort_driver = IsortDriver(self.config)
         for node, modname in self._imports_stack:
             if modname.startswith("."):
                 package = "." + modname.split(".")[1]
@@ -723,7 +718,7 @@ def _check_imports_order(self, _module_node):
             ignore_for_import_order = not self.linter.is_message_enabled(
                 "wrong-import-order", node.fromlineno
             )
-            import_category = isort_obj.place_module(package)
+            import_category = isort_driver.place_module(package)
             node_and_package_import = (node, package)
             if import_category in ("FUTURE", "STDLIB"):
                 std_imports.append(node_and_package_import)

pylint/checkers/spelling.py

@@ -21,7 +21,6 @@
 
 """Checker for spelling errors in comments and docstrings.
 """
-
 import os
 import re
 import tokenize
@@ -33,12 +32,12 @@
 try:
     import enchant
     from enchant.tokenize import (  # type: ignore
-        get_tokenizer,
         Chunker,
-        Filter,
         EmailFilter,
+        Filter,
         URLFilter,
         WikiWordFilter,
+        get_tokenizer,
     )
 except ImportError:
     enchant = None

pylint/checkers/utils.py

@@ -50,13 +50,12 @@
 from functools import lru_cache, partial
 from typing import Callable, Dict, Iterable, List, Match, Optional, Set, Tuple, Union
 
+import _string
 import astroid
 from astroid import bases as _bases
 from astroid import helpers, scoped_nodes
 from astroid.exceptions import _NonDeducibleTypeHierarchy
 
-import _string  # pylint: disable=wrong-import-position, wrong-import-order
-
 BUILTINS_NAME = builtins.__name__
 COMP_NODE_TYPES = (
     astroid.ListComp,

pylint/epylint.py

@@ -56,10 +56,10 @@
 its output.
 """
 import os
-import os.path as osp
 import shlex
 import sys
 from io import StringIO
+from os import path as osp
 from subprocess import PIPE, Popen
 
 

pylint/extensions/docparams.py

@@ -21,9 +21,9 @@
 """
 import astroid
 
-import pylint.extensions._check_docs_utils as utils
 from pylint.checkers import BaseChecker
 from pylint.checkers import utils as checker_utils
+from pylint.extensions import _check_docs_utils as utils
 from pylint.interfaces import IAstroidChecker
 
 

pylint/graph.py

@@ -13,13 +13,12 @@
 
 (dot generation adapted from pypy/translator/tool/make_dot.py)
 """
-
 import codecs
 import os
-import os.path as osp
 import subprocess
 import sys
 import tempfile
+from os import path as osp
 
 
 def target_info_from_filename(filename):

pylint/utils/__init__.py

@@ -46,6 +46,8 @@
 from pylint.utils.ast_walker import ASTWalker
 from pylint.utils.file_state import FileState
 from pylint.utils.utils import (
+    HAS_ISORT_5,
+    IsortDriver,
     _basename_in_blacklist_re,
     _check_csv,
     _format_option_value,

pylint/utils/utils.py

@@ -1,6 +1,15 @@
 # Licensed under the GPL: https://www.gnu.org/licenses/old-licenses/gpl-2.0.html
 # For details: https://github.com/PyCQA/pylint/blob/master/COPYING
 
+try:
+    import isort.api
+
+    HAS_ISORT_5 = True
+except ImportError:  # isort < 5
+    import isort
+
+    HAS_ISORT_5 = False
+
 import codecs
 import os
 import re
@@ -398,3 +407,29 @@ def _ini_format(stream, options):
                 # remove trailing ',' from last element of the list
                 value = value[:-1]
             print("%s=%s" % (optname, value), file=stream)
+
+
+class IsortDriver:
+    """A wrapper around isort API that changed between versions 4 and 5."""
+
+    def __init__(self, config):
+        if HAS_ISORT_5:
+            self.isort5_config = isort.api.Config(
+                # There is not typo here. EXTRA_standard_library is
+                # what most users want. The option has been named
+                # KNOWN_standard_library for ages in pylint and we
+                # don't want to break compatibility.
+                extra_standard_library=config.known_standard_library,
+                known_third_party=config.known_third_party,
+            )
+        else:
+            self.isort4_obj = isort.SortImports(  # pylint: disable=no-member
+                file_contents="",
+                known_standard_library=config.known_standard_library,
+                known_third_party=config.known_third_party,
+            )
+
+    def place_module(self, package):
+        if HAS_ISORT_5:
+            return isort.api.place_module(package, self.isort5_config)
+        return self.isort4_obj.place_module(package)

setup.py

@@ -39,8 +39,8 @@
 
     USE_SETUPTOOLS = 1
 except ImportError:
-    from distutils.core import setup
     from distutils.command import install_lib  # pylint: disable=unused-import
+    from distutils.core import setup
 
     USE_SETUPTOOLS = 0
     easy_install_lib = None

tests/checkers/unittest_typecheck.py

@@ -26,7 +26,7 @@
 from pylint.testutils import CheckerTestCase, Message, set_config
 
 try:
-    import coverage.tracer as _
+    from coverage import tracer as _  # pylint: disable=unused-import
 
     C_EXTENTIONS_AVAILABLE = True
 except ImportError:

tests/extensions/test_bad_builtin.py

@@ -8,8 +8,7 @@
 
 """Tests for the pylint checker in :mod:`pylint.extensions.bad_builtin
 """
-
-import os.path as osp
+from os import path as osp
 
 import pytest
 

tests/extensions/test_broad_try_clause.py

@@ -8,9 +8,8 @@
 # For details: https://github.com/PyCQA/pylint/blob/master/COPYING
 
 """Tests for the pylint checker in :mod:`pylint.extensions.broad_try_clause`"""
-
-import os.path as osp
 import unittest
+from os import path as osp
 
 from pylint import checkers
 from pylint.extensions.broad_try_clause import BroadTryClauseChecker

tests/extensions/test_check_docs_utils.py

@@ -14,7 +14,7 @@
 import astroid
 import pytest
 
-import pylint.extensions._check_docs_utils as utils
+from pylint.extensions import _check_docs_utils as utils
 
 
 @pytest.mark.parametrize(

tests/extensions/test_check_mccabe.py

@@ -10,7 +10,7 @@
 """Tests for the pylint checker in :mod:`pylint.extensions.check_mccabe"""
 # pylint: disable=redefined-outer-name
 
-import os.path as osp
+from os import path as osp
 
 import pytest
 

tests/extensions/test_elseif_used.py

@@ -9,8 +9,7 @@
 
 """Tests for the pylint checker in :mod:`pylint.extensions.check_elif
 """
-
-import os.path as osp
+from os import path as osp
 
 import pytest
 

tests/extensions/test_emptystring.py

@@ -12,8 +12,7 @@
 
 """Tests for the pylint checker in :mod:`pylint.extensions.emptystring
 """
-
-import os.path as osp
+from os import path as osp
 
 import pytest
 

tests/extensions/test_redefined.py

@@ -7,8 +7,7 @@
 # For details: https://github.com/PyCQA/pylint/blob/master/COPYING
 
 """Tests for the pylint checker in :mod:`pylint.extensions.check_elif"""
-
-import os.path as osp
+from os import path as osp
 
 import pytest
 

tests/functional/w/wrong_import_order.txt

@@ -1,6 +1,6 @@
 wrong-import-order:12::standard import "import os.path" should be placed before "import six"
 wrong-import-order:14::standard import "import sys" should be placed before "import six"
 wrong-import-order:15::standard import "import datetime" should be placed before "import six"
-wrong-import-order:18::first party import "import totally_missing" should be placed before "from .package import Class"
-wrong-import-order:20::third party import "import astroid" should be placed before "import unused_import"
-wrong-import-order:24::third party import "from six.moves.urllib.parse import quote" should be placed before "import unused_import"
+wrong-import-order:18::third party import "import totally_missing" should be placed before "from .package import Class"
+wrong-import-order:20::third party import "import astroid" should be placed before "from .package import Class"
+wrong-import-order:24::third party import "from six.moves.urllib.parse import quote" should be placed before "from .package import Class"

tests/lint/unittest_lint.py

@@ -47,8 +47,7 @@
 
 import pytest
 
-import pylint.testutils as testutils
-from pylint import checkers, config, exceptions, interfaces, lint
+from pylint import checkers, config, exceptions, interfaces, lint, testutils
 from pylint.checkers.utils import check_messages
 from pylint.constants import (
     MSG_STATE_CONFIDENCE,

tests/test_functional.py

@@ -28,6 +28,7 @@
 import pytest
 
 from pylint import testutils
+from pylint.utils import HAS_ISORT_5
 
 
 class test_dialect(csv.excel):
@@ -77,6 +78,10 @@ def get_tests():
             continue
         for filename in filenames:
             if filename != "__init__.py" and filename.endswith(".py"):
+                # isort 5 has slightly different rules as isort 4. Testing
+                # both would be hard: test with isort 5 only.
+                if filename == "wrong_import_order.py" and not HAS_ISORT_5:
+                    continue
                 suite.append(testutils.FunctionalTestFile(dirpath, filename))
     return suite
 

tests/test_import_graph.py

@@ -18,7 +18,7 @@
 
 import pytest
 
-import pylint.testutils as testutils
+from pylint import testutils
 from pylint.checkers import imports, initialize
 from pylint.lint import PyLinter
 

tests/test_regr.py

@@ -24,7 +24,7 @@
 import astroid
 import pytest
 
-import pylint.testutils as testutils
+from pylint import testutils
 
 REGR_DATA = join(dirname(abspath(__file__)), "regrtest_data")
 sys.path.insert(1, REGR_DATA)

tests/unittest_pyreverse_diadefs.py

@@ -19,6 +19,7 @@
 
 import astroid
 import pytest
+from unittest_pyreverse_writer import Config, get_project
 
 from pylint.pyreverse.diadefslib import (
     ClassDiadefGenerator,
@@ -27,7 +28,6 @@
     DiadefsHandler,
 )
 from pylint.pyreverse.inspector import Linker
-from unittest_pyreverse_writer import Config, get_project
 
 
 def _process_classes(classes):