Type Checking in CI (#3705)

* add mypy type hinting machinery and CI testing

.github/workflows/mypy.yaml

@@ -0,0 +1,51 @@
+name: "mypy"
+on:
+  push:
+    branches:
+      - develop
+  pull_request:
+    branches:
+      - develop
+
+concurrency:
+
+  group: "${{ github.ref }}-${{ github.head_ref }}-${{ github.workflow }}"
+  cancel-in-progress: true
+
+defaults:
+  run:
+    shell: bash -l {0}
+
+jobs:
+  mypy :
+    if: "github.repository == 'MDAnalysis/mdanalysis'"
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: setup_miniconda
+        uses: conda-incubator/setup-miniconda@v2
+        with:
+          python-version: 3.8
+          auto-update-conda: true
+          channel-priority: flexible
+          channels: conda-forge, bioconda
+          add-pip-as-python-dependency: true
+          mamba-version: "*"
+          architecture: x64
+
+      - name: install_deps
+        uses: ./.github/actions/setup-deps
+        with:
+          mamba: true
+          full-deps: true
+          numpy: numpy=1.20.0
+
+      - name: install
+        run: |
+          python -m pip install mypy
+
+      - name: "Run mypy"
+        run: |
+          mypy package/MDAnalysis/

mypy.ini

@@ -0,0 +1,54 @@
+[mypy]
+ignore_missing_imports = True
+exclude = doc/sphinx/source/
+
+
+[mypy-MDAnalysis.analysis.*]
+ignore_errors = True
+
+[mypy-MDAnalysis.auxiliary.*]
+ignore_errors = True
+
+[mypy-MDAnalysis.converters.*]
+ignore_errors = True
+
+[mypy-MDAnalysis.coordinates.*]
+ignore_errors = True
+
+[mypy-MDAnalysis.core.*]
+ignore_errors = True
+
+[mypy-MDAnalysis.lib.*]
+ignore_errors = True
+
+[mypy-MDAnalysis.selections.*]
+ignore_errors = True
+
+[mypy-MDAnalysis.tests.*]
+ignore_errors = True
+
+[mypy-MDAnalysis.topology.*]
+ignore_errors = True
+
+[mypy-MDAnalysis.transformations.*]
+ignore_errors = True
+
+[mypy-MDAnalysis.visualization.*]
+ignore_errors = True
+
+[mypy-MDAnalysis.due]
+ignore_errors = True
+
+[mypy-MDAnalysis.exceptions]
+ignore_errors = True
+
+[mypy-MDAnalysis.units]
+ignore_errors = True
+
+[mypy-MDAnalysis.version]
+ignore_errors = True
+
+[mypy-MDAnalysis.*]
+ignore_errors = True
+
+

mypy_requirements.txt

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+mypy==0.960
+typing_extensions