fix: support python 3.9 (#397)

.github/actions/detect-python/action.yml

@@ -0,0 +1,7 @@
+name: detect-python
+runs:
+  using: "composite"
+  steps:
+    - name: Determine Python Version
+      run: echo PYTHON_VERSION=$(cat .python-version | tr -d '\n') >> $GITHUB_ENV
+      shell: bash

.github/workflows/pythonapp.yml

@@ -11,10 +11,11 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v1
-      - name: Set up Python 3.8
+      - uses: ./.github/actions/detect-python
+      - name: Setup Python
         uses: actions/setup-python@v1
         with:
-          python-version: 3.8
+          python-version: ${{ env.PYTHON_VERSION }}
       - name: Install project dependencies
         run: |
           python -m pip install -U pip --no-cache-dir
@@ -27,7 +28,7 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest, windows-latest]
-        python-version: [3.6, 3.7, 3.8]
+        python-version: [3.6, 3.7, 3.8, 3.9]
       fail-fast: false
     steps:
       - uses: actions/checkout@v1
@@ -49,15 +50,16 @@ jobs:
     needs: [analysis, tests]
     steps:
       - uses: actions/checkout@v1
-      - name: Set up Python 3.8
+      - uses: ./.github/actions/detect-python
+      - name: Setup Python
         uses: actions/setup-python@v1
         with:
-          python-version: 3.8
+          python-version: ${{ env.PYTHON_VERSION }}
       - name: Install project dependencies
         run: |
           python -m pip install -U pip --no-cache-dir
           python -m pip install -e . -r dev_requirements.txt
-      - name: Release Python 3.8
+      - name: Release
         env:
           TWINE_USERNAME: ${{ secrets.TWINE_USERNAME }}
           TWINE_PASSWORD: ${{ secrets.TWINE_PASSWORD }}

.python-version

@@ -1 +1 @@
-3.8.1
+3.9.0

dev_requirements.txt

@@ -9,13 +9,15 @@ attrs==20.2.0             # via flake8-bugbear, pytest, syrupy
 black==20.8b1             # via syrupy
 bleach==3.2.1             # via readme-renderer
 certifi==2020.6.20        # via requests
+cffi==1.14.3              # via cryptography
 chardet==3.0.4            # via requests
 click==7.1.2              # via black, pip-tools
-codecov==2.1.10            # via syrupy
+codecov==2.1.10           # via syrupy
 colorama==0.4.4           # via twine
 colored==1.4.2            # via syrupy
 configparser==5.0.1       # via py-githooks
 coverage[toml]==5.3       # via codecov, syrupy
+cryptography==3.2.1       # via secretstorage
 deprecated==1.2.10        # via pygithub
 docutils==0.16            # via readme-renderer
 flake8-bugbear==20.1.4    # via syrupy
@@ -27,38 +29,40 @@ idna==2.10                # via requests
 iniconfig==1.1.1          # via pytest
 invoke==1.4.1             # via syrupy
 isort==5.6.4              # via syrupy
+jeepney==0.4.3            # via keyring, secretstorage
 keyring==21.4.0           # via twine
 mccabe==0.6.1             # via flake8
-more-itertools==8.5.0     # via pytest
 mypy-extensions==0.4.3    # via black, mypy
 mypy==0.790               # via syrupy
 packaging==20.4           # via bleach, pytest
 pathspec==0.8.0           # via black
 pip-tools==5.3.1          # via syrupy
-pkginfo==1.6.1          # via twine
+pkginfo==1.6.1            # via twine
 pluggy==0.13.1            # via pytest
 py-githooks==1.1.0        # via syrupy
 py==1.9.0                 # via pytest
 pycodestyle==2.6.0        # via flake8
+pycparser==2.20           # via cffi
 pyflakes==2.2.0           # via flake8
 pygithub==1.53            # via syrupy
 pygments==2.7.2           # via readme-renderer
 pyjwt==1.7.1              # via pygithub
 pyparsing==2.4.7          # via packaging
 pyperf==2.0.0             # via syrupy
-pytest==6.1.1             # via syrupy
+pytest==6.1.2             # via syrupy
 readme-renderer==28.0     # via twine
-regex==2020.10.23          # via black
+regex==2020.10.28         # via black
 requests-toolbelt==0.9.1  # via twine
 requests==2.24.0          # via codecov, pygithub, requests-toolbelt, twine
 rfc3986==1.4.0            # via twine
+secretstorage==3.1.2      # via keyring
 semver==2.13.0            # via syrupy
-six==1.15.0               # via bleach, packaging, pip-tools, readme-renderer
+six==1.15.0               # via bleach, cryptography, packaging, pip-tools, readme-renderer
 toml==0.10.1              # via black, coverage, pytest
 tqdm==4.51.0              # via twine
 twine==3.2.0              # via syrupy
 typed-ast==1.4.1          # via black, mypy
-typing-extensions==3.7.4.3  # via black, mypy, syrupy
+typing-extensions==3.7.4.3  # via black, mypy
 urllib3==1.25.11          # via requests
 webencodings==0.5.1       # via bleach
 wheel==0.35.1             # via syrupy

setup.py

@@ -11,7 +11,7 @@
 install_requires = [
     "attrs>=18.2.0,<21.0.0",
     "colored>=1.3.92,<2.0.0",
-    "typing_extensions>=3.6,<4.0.0",
+    "typing_extensions>=3.6,<4.0.0; python_version < '3.7.0'",
     "pytest>=5.1.0,<7.0.0",
 ]
 test_requires = [
@@ -78,6 +78,11 @@ def readme() -> str:
             "Intended Audience :: Developers",
             "Operating System :: OS Independent",
             "Programming Language :: Python :: 3",
+            "Programming Language :: Python :: 3.6",
+            "Programming Language :: Python :: 3.7",
+            "Programming Language :: Python :: 3.8",
+            "Programming Language :: Python :: 3.9",
             "Topic :: Software Development :: Libraries",
+            "Topic :: Software Development :: Testing",
         ],
     )