Fixed typing

.pre-commit-config.yaml

@@ -25,7 +25,13 @@ repos:
       - id: mypy
         # Avoid error: Duplicate module named 'setup'
         # https://github.com/python/mypy/issues/4008
+        # Keep exclude in sync with mypy own excludes
         exclude: ^tests/test_data/
+        additional_dependencies:
+          - click==8.0.1
+          - pep517==0.10.0
+          - toml==0.10.2
+          - pip==20.3.4
   - repo: https://github.com/PyCQA/bandit
     rev: 1.7.0
     hooks:

piptools/scripts/compile.py

@@ -2,7 +2,7 @@
 import shlex
 import sys
 import tempfile
-from typing import Any, BinaryIO, List, Optional, Tuple, cast
+from typing import IO, Any, BinaryIO, List, Optional, Tuple, Union, cast
 
 import click
 from click.utils import LazyFile, safecall
@@ -231,7 +231,7 @@ def cli(
     annotate: bool,
     upgrade: bool,
     upgrade_packages: Tuple[str, ...],
-    output_file: Optional[LazyFile],
+    output_file: Union[LazyFile, IO[Any], None],
     allow_unsafe: bool,
     generate_hashes: bool,
     reuse_hashes: bool,
@@ -282,7 +282,9 @@ def cli(
 
         # Close the file at the end of the context execution
         assert output_file is not None
-        ctx.call_on_close(safecall(output_file.close_intelligently))
+        # only LazyFile has close_intelligently, newer IO[Any] does not
+        if isinstance(output_file, LazyFile):  # pragma: no cover
+            ctx.call_on_close(safecall(output_file.close_intelligently))
 
     ###
     # Setup

setup.cfg

@@ -93,5 +93,9 @@ warn_return_any = true
 warn_unused_configs = true
 warn_unused_ignores = true
 
+# Avoid error: Duplicate module named 'setup'
+# https://github.com/python/mypy/issues/4008
+exclude = ^tests/test_data/
+
 [mypy-tests.*]
 disallow_untyped_defs = false