Normalize input of ``ignore-paths`` for all path types (#5201)

Closes #5194

Co-authored-by: Pierre Sassoulas <pierre.sassoulas@gmail.com>

8 files changed, 166 insertions, 43 deletions

diff --git a/ChangeLog b/ChangeLog
index 13a2d977f..be49bc113 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -82,6 +82,11 @@ Release date: TBA
 
   Closes #3031
 
+* Normalize the input to the ``ignore-paths`` option to allow both Posix and
+  Windows paths
+
+  Closes #5194
+
 * Fix double emitting of ``not-callable`` on inferrable ``properties``
 
   Closes #4426
diff --git a/doc/whatsnew/2.12.rst b/doc/whatsnew/2.12.rst
index 2a6c321fe..1126ebd53 100644
--- a/doc/whatsnew/2.12.rst
+++ b/doc/whatsnew/2.12.rst
@@ -86,6 +86,11 @@ Other Changes
 
   Closes #4426
 
+* Normalize the input to the ``ignore-paths`` option to allow both Posix and
+  Windows paths
+
+  Closes #5194
+
 * ``mising-param-doc`` now correctly parses asterisks for variable length and
   keyword parameters
 
diff --git a/pylint/config/option.py b/pylint/config/option.py
index 0a9a37069..7b3e3b1b1 100644
--- a/pylint/config/option.py
+++ b/pylint/config/option.py
@@ -3,7 +3,9 @@
 
 import copy
 import optparse  # pylint: disable=deprecated-module
+import pathlib
 import re
+from typing import List, Pattern
 
 from pylint import utils
 
@@ -25,6 +27,19 @@ def _regexp_csv_validator(_, name, value):
     return [_regexp_validator(_, name, val) for val in _csv_validator(_, name, value)]
 
 
+def _regexp_paths_csv_validator(_, name: str, value: str) -> List[Pattern[str]]:
+    patterns = []
+    for val in _csv_validator(_, name, value):
+        patterns.append(
+            re.compile(
+                str(pathlib.PureWindowsPath(val)).replace("\\", "\\\\")
+                + "|"
+                + pathlib.PureWindowsPath(val).as_posix()
+            )
+        )
+    return patterns
+
+
 def _choice_validator(choices, name, value):
     if value not in choices:
         msg = "option %s: invalid value: %r, should be in %s"
@@ -80,6 +95,7 @@ VALIDATORS = {
     "float": float,
     "regexp": lambda pattern: re.compile(pattern or ""),
     "regexp_csv": _regexp_csv_validator,
+    "regexp_paths_csv": _regexp_paths_csv_validator,
     "csv": _csv_validator,
     "yn": _yn_validator,
     "choice": lambda opt, name, value: _choice_validator(opt["choices"], name, value),
@@ -122,6 +138,7 @@ class Option(optparse.Option):
     TYPES = optparse.Option.TYPES + (
         "regexp",
         "regexp_csv",
+        "regexp_paths_csv",
         "csv",
         "yn",
         "multiple_choice",
@@ -132,6 +149,7 @@ class Option(optparse.Option):
     TYPE_CHECKER = copy.copy(optparse.Option.TYPE_CHECKER)
     TYPE_CHECKER["regexp"] = _regexp_validator
     TYPE_CHECKER["regexp_csv"] = _regexp_csv_validator
+    TYPE_CHECKER["regexp_paths_csv"] = _regexp_paths_csv_validator
     TYPE_CHECKER["csv"] = _csv_validator
     TYPE_CHECKER["yn"] = _yn_validator
     TYPE_CHECKER["multiple_choice"] = _multiple_choices_validating_option
diff --git a/pylint/lint/expand_modules.py b/pylint/lint/expand_modules.py
index 1d4432322..cea4b5c17 100644
--- a/pylint/lint/expand_modules.py
+++ b/pylint/lint/expand_modules.py
@@ -43,7 +43,7 @@ def expand_modules(
     files_or_modules: List[str],
     ignore_list: List[str],
     ignore_list_re: List[Pattern],
-    ignore_list_paths_re: List[Pattern],
+    ignore_list_paths_re: List[Pattern[str]],
 ) -> Tuple[List[ModuleDescriptionDict], List[ErrorDescriptionDict]]:
     """take a list of files/modules/packages and return the list of tuple
     (file, module name) which have to be actually checked
diff --git a/pylint/lint/pylinter.py b/pylint/lint/pylinter.py
index 6e6ccd59b..3be78c46c 100644
--- a/pylint/lint/pylinter.py
+++ b/pylint/lint/pylinter.py
@@ -46,7 +46,14 @@ from pylint.typing import (
     MessageLocationTuple,
     ModuleDescriptionDict,
 )
-from pylint.utils import ASTWalker, FileState, LinterStats, ModuleStats, utils
+from pylint.utils import (
+    ASTWalker,
+    FileState,
+    LinterStats,
+    ModuleStats,
+    get_global_option,
+    utils,
+)
 from pylint.utils.pragma_parser import (
     OPTION_PO,
     InvalidPragmaError,
@@ -220,12 +227,12 @@ class PyLinter(
             (
                 "ignore-paths",
                 {
-                    "type": "regexp_csv",
+                    "type": "regexp_paths_csv",
                     "metavar": "<pattern>[,<pattern>...]",
-                    "dest": "ignore_list_paths_re",
-                    "default": (),
-                    "help": "Add files or directories matching the regex patterns to the"
-                    " ignore-list. The regex matches against paths.",
+                    "default": [],
+                    "help": "Add files or directories matching the regex patterns to the "
+                    "ignore-list. The regex matches against paths and can be in "
+                    "Posix or Windows format.",
                 },
             ),
             (
@@ -1101,7 +1108,7 @@ class PyLinter(
             modules,
             self.config.black_list,
             self.config.black_list_re,
-            self.config.ignore_list_paths_re,
+            self._ignore_paths,
         )
         for error in errors:
             message = modname = error["mod"]
@@ -1259,6 +1266,7 @@ class PyLinter(
                 self.config.extension_pkg_whitelist
             )
         self.stats.reset_message_count()
+        self._ignore_paths = get_global_option(self, "ignore-paths")
 
     def generate_reports(self):
         """close the whole package /module, it's time to make reports !
diff --git a/pylint/utils/utils.py b/pylint/utils/utils.py
index 96f8a6acc..6c9f11298 100644
--- a/pylint/utils/utils.py
+++ b/pylint/utils/utils.py
@@ -56,16 +56,24 @@ GLOBAL_OPTION_LIST = Literal["ignored-modules"]
 GLOBAL_OPTION_PATTERN = Literal[
     "no-docstring-rgx", "dummy-variables-rgx", "ignored-argument-names"
 ]
+GLOBAL_OPTION_PATTERN_LIST = Literal["ignore-paths"]
 GLOBAL_OPTION_TUPLE_INT = Literal["py-version"]
 GLOBAL_OPTION_NAMES = Union[
     GLOBAL_OPTION_BOOL,
     GLOBAL_OPTION_INT,
     GLOBAL_OPTION_LIST,
     GLOBAL_OPTION_PATTERN,
+    GLOBAL_OPTION_PATTERN_LIST,
     GLOBAL_OPTION_TUPLE_INT,
 ]
 T_GlobalOptionReturnTypes = TypeVar(
-    "T_GlobalOptionReturnTypes", bool, int, List[str], Pattern[str], Tuple[int, ...]
+    "T_GlobalOptionReturnTypes",
+    bool,
+    int,
+    List[str],
+    Pattern[str],
+    List[Pattern[str]],
+    Tuple[int, ...],
 )
 
 
@@ -223,6 +231,15 @@ def get_global_option(
 @overload
 def get_global_option(
     checker: "BaseChecker",
+    option: GLOBAL_OPTION_PATTERN_LIST,
+    default: Optional[List[Pattern[str]]] = None,
+) -> List[Pattern[str]]:
+    ...
+
+
+@overload
+def get_global_option(
+    checker: "BaseChecker",
     option: GLOBAL_OPTION_TUPLE_INT,
     default: Optional[Tuple[int, ...]] = None,
 ) -> Tuple[int, ...]:
diff --git a/tests/lint/unittest_expand_modules.py b/tests/lint/unittest_expand_modules.py
index ef98cf575..4d679ad64 100644
--- a/tests/lint/unittest_expand_modules.py
+++ b/tests/lint/unittest_expand_modules.py
@@ -4,10 +4,14 @@
 
 import re
 from pathlib import Path
+from typing import Dict, Tuple, Type
 
 import pytest
 
+from pylint.checkers import BaseChecker
 from pylint.lint.expand_modules import _is_in_ignore_list_re, expand_modules
+from pylint.testutils import CheckerTestCase, set_config
+from pylint.utils.utils import get_global_option
 
 
 def test__is_in_ignore_list_re_match() -> None:
@@ -21,17 +25,6 @@ def test__is_in_ignore_list_re_match() -> None:
     assert _is_in_ignore_list_re("src/tests/whatever.xml", patterns)
 
 
-def test__is_in_ignore_list_re_nomatch() -> None:
-    patterns = [
-        re.compile(".*enchilada.*"),
-        re.compile("unittest_.*"),
-        re.compile(".*tests/.*"),
-    ]
-    assert not _is_in_ignore_list_re("test_utils.py", patterns)
-    assert not _is_in_ignore_list_re("enchilad.py", patterns)
-    assert not _is_in_ignore_list_re("src/tests.py", patterns)
-
-
 TEST_DIRECTORY = Path(__file__).parent.parent
 INIT_PATH = str(TEST_DIRECTORY / "lint/__init__.py")
 EXPAND_MODULES = str(TEST_DIRECTORY / "lint/unittest_expand_modules.py")
@@ -84,27 +77,70 @@ init_of_package = {
 }
 
 
-@pytest.mark.parametrize(
-    "files_or_modules,expected",
-    [
-        ([__file__], [this_file]),
-        (
-            [Path(__file__).parent],
-            [
-                init_of_package,
-                test_pylinter,
-                test_utils,
-                this_file_from_init,
-                unittest_lint,
-            ],
-        ),
-    ],
-)
-def test_expand_modules(files_or_modules, expected):
-    ignore_list, ignore_list_re, ignore_list_paths_re = [], [], []
-    modules, errors = expand_modules(
-        files_or_modules, ignore_list, ignore_list_re, ignore_list_paths_re
+class TestExpandModules(CheckerTestCase):
+    """Test the expand_modules function while allowing options to be set"""
+
+    class Checker(BaseChecker):
+        """This dummy checker is needed to allow options to be set"""
+
+        name = "checker"
+        msgs: Dict[str, Tuple[str, ...]] = {}
+        options = (("An option", {"An option": "dict"}),)
+
+    CHECKER_CLASS: Type = Checker
+
+    @pytest.mark.parametrize(
+        "files_or_modules,expected",
+        [
+            ([__file__], [this_file]),
+            (
+                [str(Path(__file__).parent)],
+                [
+                    init_of_package,
+                    test_pylinter,
+                    test_utils,
+                    this_file_from_init,
+                    unittest_lint,
+                ],
+            ),
+        ],
+    )
+    @set_config(ignore_paths="")
+    def test_expand_modules(self, files_or_modules, expected):
+        """Test expand_modules with the default value of ignore-paths"""
+        ignore_list, ignore_list_re = [], []
+        modules, errors = expand_modules(
+            files_or_modules,
+            ignore_list,
+            ignore_list_re,
+            get_global_option(self, "ignore-paths"),
+        )
+        modules.sort(key=lambda d: d["name"])
+        assert modules == expected
+        assert not errors
+
+    @pytest.mark.parametrize(
+        "files_or_modules,expected",
+        [
+            ([__file__], []),
+            (
+                [str(Path(__file__).parent)],
+                [
+                    init_of_package,
+                ],
+            ),
+        ],
     )
-    modules.sort(key=lambda d: d["name"])
-    assert modules == expected
-    assert not errors
+    @set_config(ignore_paths=".*/lint/.*")
+    def test_expand_modules_with_ignore(self, files_or_modules, expected):
+        """Test expand_modules with a non-default value of ignore-paths"""
+        ignore_list, ignore_list_re = [], []
+        modules, errors = expand_modules(
+            files_or_modules,
+            ignore_list,
+            ignore_list_re,
+            get_global_option(self.checker, "ignore-paths"),
+        )
+        modules.sort(key=lambda d: d["name"])
+        assert modules == expected
+        assert not errors
diff --git a/tests/unittest_config.py b/tests/unittest_config.py
index 9be02fc4c..9979aa41b 100644
--- a/tests/unittest_config.py
+++ b/tests/unittest_config.py
@@ -16,10 +16,14 @@
 
 import re
 import sre_constants
+from typing import Dict, Tuple, Type
 
 import pytest
 
 from pylint import config
+from pylint.checkers import BaseChecker
+from pylint.testutils import CheckerTestCase, set_config
+from pylint.utils.utils import get_global_option
 
 RE_PATTERN_TYPE = getattr(re, "Pattern", getattr(re, "_pattern_type", None))
 
@@ -65,3 +69,33 @@ def test__regexp_csv_validator_invalid() -> None:
     pattern_strings = ["test_.*", "foo\\.bar", "^baz)$"]
     with pytest.raises(sre_constants.error):
         config.option._regexp_csv_validator(None, None, ",".join(pattern_strings))
+
+
+class TestPyLinterOptionSetters(CheckerTestCase):
+    """Class to check the set_config decorator and get_global_option util
+    for options declared in PyLinter."""
+
+    class Checker(BaseChecker):
+        name = "checker"
+        msgs: Dict[str, Tuple[str, ...]] = {}
+        options = (("An option", {"An option": "dict"}),)
+
+    CHECKER_CLASS: Type = Checker
+
+    @set_config(ignore_paths=".*/tests/.*,.*\\ignore\\.*")
+    def test_ignore_paths_with_value(self) -> None:
+        """Test ignore-paths option with value"""
+        options = get_global_option(self.checker, "ignore-paths")
+
+        assert any(i.match("dir/tests/file.py") for i in options)
+        assert any(i.match("dir\\tests\\file.py") for i in options)
+        assert any(i.match("dir/ignore/file.py") for i in options)
+        assert any(i.match("dir\\ignore\\file.py") for i in options)
+
+    def test_ignore_paths_with_no_value(self) -> None:
+        """Test ignore-paths option with no value.
+        Compare against actual list to see if validator works."""
+        options = get_global_option(self.checker, "ignore-paths")
+
+        # pylint: disable-next=use-implicit-booleaness-not-comparison
+        assert options == []