make mypy_3.6: Still check the types in a Python 3.6 context, but using Py 3.7+

Author: mr-c

.github/workflows/ci-tests.yml

@@ -25,6 +25,10 @@ jobs:
         py-ver-major: [3]
         py-ver-minor: [6, 7, 8, 9, 10]
         step: [lint, unit, bandit, mypy]
+        exclude:
+          - py-ver-major: 3
+            py-ver-minor: 6
+            step: mypy
 
     env:
       py-semver: ${{ format('{0}.{1}', matrix.py-ver-major, matrix.py-ver-minor) }}

Makefile

@@ -171,6 +171,9 @@ mypy3: mypy
 mypy: $(filter-out setup.py,${PYSOURCES})
 	MYPYPATH=$$MYPYPATH:mypy-stubs mypy $^
 
+mypy_3.6: $(filter-out setup.py,${PYSOURCES})
+	MYPYPATH=$$MYPYPATH:mypy-stubs mypy --python-version 3.6 $^
+
 shellcheck: FORCE
 	shellcheck release-test.sh
 

tox.ini

@@ -3,7 +3,7 @@ envlist =
   py{36,37,38,39,310}-lint,
   py{36,37,38,39,310}-unit,
   py{36,37,38,39,310}-bandit,
-  py{36,37,38,39,310}-mypy,
+  py{37,38,39,310}-mypy,
   py310-lint-readme,
   py310-pydocstyle
 
@@ -25,7 +25,7 @@ description =
   py{36,37,38,39,310}-unit: Run the unit tests
   py{36,37,38,39,310}-lint: Lint the Python code
   py{36,37,38,39,310}-bandit: Search for common security issues
-  py{36,37,38,39,310}-mypy: Check for type safety
+  py{37,38,39,310}-mypy: Check for type safety
   py310-pydocstyle: docstring style checker
   py310-lint-readme: Lint the README.rst->.md conversion
 
@@ -49,7 +49,8 @@ commands =
   py{36,37,38,39,310}-bandit: bandit --recursive cwl_utils
   py{36,37,38,39,310}-lint: make flake8
   py{36,37,38,39,310}-lint: make format-check
-  py{36,37,38,39,310}-mypy: make mypy
+  py{37,38,39,310}-mypy: make mypy
+  py37-mypy: make mypy_3.6
 
 whitelist_externals =
   py{36,37,38,39,310}-lint: flake8