Check codebase using mypy in github actions

.github/workflows/dist.yml

@@ -16,6 +16,22 @@ jobs:
     - uses: actions/checkout@v2
     - uses: psf/black@stable
   
+  check-mypy:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    # - uses: jpetrucciani/mypy-check@0.930
+    # .. can't use that because we need to install pytest
+    - uses: actions/setup-python@v2
+      with:
+        python-version: 3.8
+    - name: Install requirements
+      run: |
+        pip --disable-pip-version-check install mypy pytest
+    - name: Run mypy
+      run: |
+        mypy .
+
   check-doc:
     runs-on: ubuntu-18.04
     
@@ -77,7 +93,7 @@ jobs:
 
   publish:
     runs-on: ubuntu-latest
-    needs: [check, check-doc, test]
+    needs: [check, check-mypy, check-doc, test]
     if: github.event_name == 'push' && startsWith(github.event.ref, 'refs/tags')
 
     steps:

mypy.ini

@@ -0,0 +1,5 @@
+[mypy]
+exclude = setup\.py|docs
+
+[mypy-cxxheaderparser._ply.*]
+ignore_errors = True

setup.py

@@ -71,6 +71,7 @@ setup(
     license="BSD",
     platforms="Platform Independent",
     packages=find_packages(),
+    package_data={"cxxheaderparser": ["py.typed"]},
     keywords="c++ header parser ply",
     python_requires=">= 3.6",
     classifiers=CLASSIFIERS,