Remove redundant 3.6 code and bump mypy's python_version to 3.7 (#3313)

Author: hugovk

autoload/black.vim

@@ -57,8 +57,8 @@ def _get_virtualenv_site_packages(venv_path, pyver):
 
 def _initialize_black_env(upgrade=False):
   pyver = sys.version_info[:3]
-  if pyver < (3, 6, 2):
-    print("Sorry, Black requires Python 3.6.2+ to run.")
+  if pyver < (3, 7):
+    print("Sorry, Black requires Python 3.7+ to run.")
     return False
 
   from pathlib import Path

mypy.ini

@@ -2,7 +2,7 @@
 # Specify the target platform details in config, so your developers are
 # free to run mypy on Windows, Linux, or macOS and get consistent
 # results.
-python_version=3.6
+python_version=3.7
 
 mypy_path=src
 
@@ -19,11 +19,6 @@ no_implicit_reexport = False
 # to avoid 'em in the first place.
 warn_unreachable=True
 
-[mypy-black]
-# The following is because of `patch_click()`. Remove when
-# we drop Python 3.6 support.
-warn_unused_ignores=False
-
 [mypy-blib2to3.driver.*]
 ignore_missing_imports = True
 

src/black/__init__.py

@@ -1382,9 +1382,9 @@ def patch_click() -> None:
 
     for module in modules:
         if hasattr(module, "_verify_python3_env"):
-            module._verify_python3_env = lambda: None  # type: ignore
+            module._verify_python3_env = lambda: None
         if hasattr(module, "_verify_python_env"):
-            module._verify_python_env = lambda: None  # type: ignore
+            module._verify_python_env = lambda: None
 
 
 def patched_main() -> None:

src/black/concurrency.py

@@ -47,12 +47,8 @@ def cancel(tasks: Iterable["asyncio.Task[Any]"]) -> None:
 def shutdown(loop: asyncio.AbstractEventLoop) -> None:
     """Cancel all pending tasks on `loop`, wait for them, and close the loop."""
     try:
-        if sys.version_info[:2] >= (3, 7):
-            all_tasks = asyncio.all_tasks
-        else:
-            all_tasks = asyncio.Task.all_tasks
         # This part is borrowed from asyncio/runners.py in Python 3.7b2.
-        to_cancel = [task for task in all_tasks(loop) if not task.done()]
+        to_cancel = [task for task in asyncio.all_tasks(loop) if not task.done()]
         if not to_cancel:
             return
 

src/black/parsing.py

@@ -27,8 +27,7 @@
 try:
     from typed_ast import ast3
 except ImportError:
-    # Either our python version is too low, or we're on pypy
-    if sys.version_info < (3, 7) or (sys.version_info < (3, 8) and not _IS_PYPY):
+    if sys.version_info < (3, 8) and not _IS_PYPY:
         print(
             "The typed_ast package is required but not installed.\n"
             "You can upgrade to Python 3.8+ or install typed_ast with\n"