Python support: remove 3.6, add 3.10

Resolves #343

.github/workflows/checks.yml

@@ -12,7 +12,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: [3.6, 3.7, 3.8, 3.9]
+        python-version: [3.7, 3.8, 3.9, 3.10]
 
     steps:
     - uses: actions/checkout@v2

CHANGELOG.md

@@ -1,5 +1,13 @@
 # Change Log
 
+## Unreleased
+
+### Python Versions
+
+* Removed Python 3.6 support ([#343])
+* Added Python 3.10 support ([#343])
+
+
 ## [v1.6.0]
 
 **Release date: 2021-09-30**
@@ -1521,3 +1529,4 @@ information about changes, except for
 [#331]: https://github.com/delph-in/pydelphin/issues/331
 [#333]: https://github.com/delph-in/pydelphin/issues/333
 [#334]: https://github.com/delph-in/pydelphin/issues/334
+[#343]: https://github.com/delph-in/pydelphin/issues/343

CONTRIBUTING.md

@@ -32,7 +32,7 @@ For bug requests, please provide the following, if possible:
   >>> mrs.__version__  # package version
   '1.6.0'
   ```
-* Python version (e.g. 3.6, 3.7, etc.)
+* Python version (e.g. 3.7, 3.8, etc.)
 
 For feature requests, please provide a use case for the feature.
 

docs/guides/setup.rst

@@ -19,7 +19,7 @@ its source files.
 Requirements
 ------------
 
-PyDelphin works with Python 3.6 and higher, regardless of the
+PyDelphin works with Python 3.7 and higher, regardless of the
 platform. Certain features, however, may require additional
 dependencies or may be platform specific, as shown in the table below:
 

setup.py

@@ -47,10 +47,10 @@
         'Intended Audience :: Science/Research',
         'License :: OSI Approved :: MIT License',
         '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 :: Scientific/Engineering :: Information Analysis',
         'Topic :: Software Development :: Libraries :: Python Modules',
         'Topic :: Text Processing :: Linguistic',

tests/tdl_test.py

@@ -495,8 +495,6 @@ def test_parse_cons_list():
         tdlparse('a := b & [ ATTR < [] [] > ].')
 
 
-@pytest.mark.skipif(sys.version_info < (3, 7),
-                    reason='recursion test is flaky on Python 3.6')
 @pytest.mark.slow
 def test_issue_294():
     # check for recursion error