style: add a few more checks

.pre-commit-config.yaml

@@ -1,22 +1,25 @@
 repos:
--   repo: https://gitlab.com/pycqa/flake8
+- repo: https://gitlab.com/pycqa/flake8
-    rev: 3.8.3
+  rev: 3.8.3
-    hooks:
+  hooks:
-    - id: flake8
+  - id: flake8
-      pass_filenames: true
+    exclude: cibuildwheel/resources/
-      # this seems to need to be here in addition to setup.cfg
+    additional_dependencies: [flake8-bugbear]
-      exclude: cibuildwheel/resources/
+
--   repo: https://github.com/pre-commit/pre-commit-hooks
+- repo: https://github.com/pre-commit/pre-commit-hooks
-    rev: v3.2.0
+  rev: v3.2.0
-    hooks:
+  hooks:
-    - id: check-yaml
+  - id: check-case-conflict
-    - id: check-merge-conflict
+  - id: check-merge-conflict
-    - id: end-of-file-fixer
+  - id: check-yaml
-      exclude: cibuildwheel/resources/pinned_docker_images.cfg
+  - id: end-of-file-fixer
--   repo: https://github.com/pre-commit/mirrors-mypy
+    exclude: cibuildwheel/resources/pinned_docker_images.cfg
-    rev: v0.782
+  - id: mixed-line-ending
-    hooks:
+  - id: trailing-whitespace
-    - id: mypy
+
-      files: cibuildwheel/|test/
+- repo: https://github.com/pre-commit/mirrors-mypy
-      entry: mypy
+  rev: v0.782
-      pass_filenames: false
+  hooks:
+  - id: mypy
+    files: cibuildwheel/|test/
+    pass_filenames: false

cibuildwheel/docker_container.py

@@ -117,11 +117,12 @@ class DockerContainer:
 
         return [PurePath(p) for p in path_strs]
 
-    def call(self, args: Sequence[Union[str, PathLike]], env: Dict[str, str] = {},
+    def call(self, args: Sequence[Union[str, PathLike]], env: Optional[Dict[str, str]] = None,
              capture_output=False, cwd: Optional[Union[str, PathLike]] = None) -> str:
+
         chdir = f'cd {cwd}' if cwd else ''
         env_assignments = ' '.join(f'{shlex.quote(k)}={shlex.quote(v)}'
-                                   for k, v in env.items())
+                                   for k, v in env.items()) if env is not None else ''
         command = ' '.join(shlex.quote(str(a)) for a in args)
         end_of_message = str(uuid.uuid4())
 

setup.cfg

@@ -1,5 +1,6 @@
 [flake8]
-ignore = E501,W503,E741,E226
+ignore = E501,W503,E741,E226,B950
+select = C,E,F,W,B,B9
 application-import-names = cibuildwheel
 exclude =
   cibuildwheel/resources/,