infra: add CI test for MinGW

Author: msiemens

.github/workflows/ci-workflow.yml

@@ -49,3 +49,28 @@ jobs:
         COVERALLS_REPO_TOKEN: ${{ secrets.COVERALLS_REPO_TOKEN }}
       run: |
         uv run coveralls
+
+  mingw:
+    name: MinGW (MSYS2)
+    runs-on: windows-latest
+    steps:
+    - uses: actions/checkout@v4
+    - name: Set up MSYS2 (MinGW64)
+      uses: msys2/setup-msys2@v2
+      with:
+        msystem: MINGW64
+        update: true
+        install: >-
+          mingw-w64-x86_64-python
+          mingw-w64-x86_64-python-pip
+          git
+    - name: Install dependencies
+      shell: msys2 {0}
+      run: |
+        python -m pip install -U pip
+        pip install -e .
+        pip install pytest pytest-cov
+    - name: Run test suite
+      shell: msys2 {0}
+      run: |
+        pytest -v --cov=PyGitUp