Add support for Python 3.10 (#986)

* Add support for Python 3.10

* YAPF supports Python 2.7 and 3.6.4+

* Add support for Python 3.10

.github/workflows/ci.yml

@@ -11,7 +11,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        python-version: [2.7, 3.7, 3.8, 3.9]
+        python-version: ["2.7", "3.7", "3.8", "3.9", "3.10"]
         os: [ubuntu-latest, macos-latest]
 
     steps:

CHANGELOG

@@ -5,6 +5,7 @@
 ## [0.40.0] UNRELEASED
 ### Changes
 - Moved 'pytree' parsing tools into its own subdirectory.
+- Add support for Python 3.10.
 
 ## [0.32.0] 2021-12-26
 ### Added

setup.py

@@ -61,6 +61,10 @@ with codecs.open('README.rst', 'r', 'utf-8') as fd:
           'Programming Language :: Python :: 2.7',
           'Programming Language :: Python :: 3',
           'Programming Language :: Python :: 3.6',
+          'Programming Language :: Python :: 3.7',
+          'Programming Language :: Python :: 3.8',
+          'Programming Language :: Python :: 3.9',
+          'Programming Language :: Python :: 3.10',
           'Topic :: Software Development :: Libraries :: Python Modules',
           'Topic :: Software Development :: Quality Assurance',
       ],

tox.ini

@@ -1,5 +1,5 @@
 [tox]
-envlist=py27,py34,py35,py36,py37,py38
+envlist=py27,py36,py37,py38,py39,py310
 
 [testenv]
 commands=

yapf/yapflib/yapf_api.py

@@ -198,12 +198,12 @@ def FormatCode(unformatted_source,
 
 
 def _CheckPythonVersion():  # pragma: no cover
-  errmsg = 'yapf is only supported for Python 2.7 or 3.4+'
+  errmsg = 'yapf is only supported for Python 2.7 or 3.6+'
   if sys.version_info[0] == 2:
     if sys.version_info[1] < 7:
       raise RuntimeError(errmsg)
   elif sys.version_info[0] == 3:
-    if sys.version_info[1] < 4:
+    if sys.version_info[1] < 6:
       raise RuntimeError(errmsg)