Use ty instead of MyPy for type checking

.github/workflows/check.yml

@@ -25,7 +25,7 @@ jobs:
         env:
         - lint
         - format
-        - mypy
+        - types
         - package
         - license
     steps:

pyclean/runner.py

@@ -4,25 +4,36 @@
 
 """Cleanup runner with dry-run and file operations functionality."""
 
+from __future__ import annotations
+
 import logging
+from typing import TYPE_CHECKING
+
+if TYPE_CHECKING:
+    from argparse import Namespace
+    from pathlib import Path
 
 log = logging.getLogger(__name__)
 
 
+def noop(_: Path) -> None:
+    """No-op function for uninitialized runner."""
+
+
 class CleanupRunner:
     """Execution engine with object counting, logging and optional dry-run."""
 
     def __init__(self):
         """Cleanup runner with optional dry-run behavior."""
-        self.unlink = None
-        self.rmdir = None
-        self.ignore = None
-        self.unlink_count = None
-        self.unlink_failed = None
-        self.rmdir_count = None
-        self.rmdir_failed = None
-
-    def configure(self, args):
+        self.unlink = noop
+        self.rmdir = noop
+        self.ignore: list[str] = []
+        self.unlink_count = 0
+        self.unlink_failed = 0
+        self.rmdir_count = 0
+        self.rmdir_failed = 0
+
+    def configure(self, args: Namespace) -> None:
         """Set up runner according to command line options."""
         self.unlink = print_filename if args.dry_run else remove_file
         self.rmdir = print_dirname if args.dry_run else remove_directory
@@ -36,7 +47,7 @@ def configure(self, args):
 Runner = CleanupRunner()
 
 
-def remove_file(fileobj):
+def remove_file(fileobj: Path) -> None:
     """Attempt to delete a file object for real."""
     log.debug('Deleting file: %s', fileobj)
     try:
@@ -47,7 +58,7 @@ def remove_file(fileobj):
         Runner.unlink_failed += 1
 
 
-def remove_directory(dirobj):
+def remove_directory(dirobj: Path) -> None:
     """Attempt to remove a directory object for real."""
     log.debug('Removing directory: %s', dirobj)
     try:
@@ -58,13 +69,13 @@ def remove_directory(dirobj):
         Runner.rmdir_failed += 1
 
 
-def print_filename(fileobj):
+def print_filename(fileobj: Path) -> None:
     """Only display the file name, used with --dry-run."""
     log.debug('Would delete file: %s', fileobj)
     Runner.unlink_count += 1
 
 
-def print_dirname(dirobj):
+def print_dirname(dirobj: Path) -> None:
     """Only display the directory name, used with --dry-run."""
     log.debug('Would delete directory: %s', dirobj)
     Runner.rmdir_count += 1

pyclean/traversal.py

@@ -4,6 +4,8 @@
 
 """Directory traversal and ignore pattern matching."""
 
+from __future__ import annotations
+
 import logging
 import os
 from pathlib import Path
@@ -23,7 +25,7 @@ def normalize(path_pattern: str) -> str:
     return path_pattern.replace(os.sep, os.altsep or os.sep)
 
 
-def should_ignore(pathname: str, ignore_patterns: list[str]) -> bool:
+def should_ignore(pathname: str, ignore_patterns: list[str] | None) -> bool:
     """
     Check if a path should be ignored based on ignore patterns.
 

pyproject.toml

@@ -58,19 +58,6 @@ exclude_also = ["if __name__ == .__main__.:"]
 show_missing = true
 skip_covered = true
 
-[tool.mypy]
-exclude = [
-  "tests/",
-  "tests\\.py$",
-  "test_.*\\.py$",
-  ".*_tests\\.py$",
-]
-ignore_missing_imports = true
-pretty = true
-warn_redundant_casts = true
-warn_unreachable = true
-warn_unused_ignores = true
-
 [tool.pytest.ini_options]
 addopts = "--color=yes --doctest-modules --junitxml=tests/junit-report.xml --verbose"
 

tests/test_traversal.py

@@ -92,8 +92,7 @@ def test_should_ignore(path_str, patterns, expected):
     """
     Does should_ignore correctly match path patterns?
     """
-    path = Path(path_str)
-    result = should_ignore(path, patterns)
+    result = should_ignore(path_str, patterns)
     assert result == expected
 
 
@@ -112,8 +111,7 @@ def test_should_ignore_windows_paths(path_str, patterns, expected):
     Does should_ignore correctly handle Windows-style backslash patterns?
     This test only runs on Windows where backslash is a path separator.
     """
-    path = Path(path_str)
-    result = should_ignore(path, patterns)
+    result = should_ignore(path_str, patterns)
     assert result == expected
 
 

tox.ini

@@ -8,8 +8,8 @@
 envlist =
     lint
     format
+    types
     license
-    mypy
     py3{9,10,11,12,13,14}
     pypy3{9,10,11}
     package
@@ -59,12 +59,6 @@ skip_install = true
 deps = ruff
 commands = ruff check {posargs:.}
 
-[testenv:mypy]
-description = Perform static type checking
-skip_install = true
-deps = mypy
-commands = mypy {posargs:.}
-
 [testenv:package]
 description = Build package and check metadata (or upload package)
 skip_install = true
@@ -78,3 +72,12 @@ passenv =
     TWINE_USERNAME
     TWINE_PASSWORD
     TWINE_REPOSITORY_URL
+
+[testenv:types]
+description = Perform static type checking
+skip_install = true
+deps =
+    cli-test-helpers
+    pytest
+    ty
+commands = ty check {posargs}