Add a GitHub Actions workflow for automatic PyPi publishing whenever …

…creating a new release

.github/workflows/publish.yml

@@ -0,0 +1,94 @@
+name: Publish to PyPi
+
+on:
+  release:
+    types: [published]
+
+jobs:
+  build-package:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Set up Python
+        uses: actions/setup-python@v4
+        with:
+          python-version: '3.x'
+
+      - name: Install dependencies
+        run: |
+          python -m pip install --upgrade pip
+          pip install setuptools wheel twine
+
+      - name: Build package
+        run: python setup.py sdist bdist_wheel
+
+      - name: Upload package artifact
+        uses: actions/upload-artifact@v4
+        with:
+          name: package
+          path: dist
+
+  test-package:
+    needs: build-package
+
+    strategy:
+      matrix:
+        os: [ ubuntu-latest, macos-latest, windows-latest ]
+        python-version: [ "3.8", "3.9", "3.10", "3.11" ]
+
+    runs-on: ${{ matrix.os }}
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Set Up Python ${{ matrix.python-version }}
+        uses: actions/setup-python@v4
+        with:
+          python-version: ${{ matrix.python-version }}
+
+      - name: Download package artifact
+        uses: actions/download-artifact@v4
+        with:
+          name: package
+          path: dist
+
+      - name: Install package and dependencies
+        run: |
+          python -m pip install --upgrade pip
+          pip install dist/plams-*.whl
+          pip install ".[chem_tools,results]"
+          pip install pytest
+
+      - name: Run Unit Tests
+        run: |
+          pytest unit_tests
+
+  publish-package:
+    runs-on: ubuntu-latest
+
+    needs: test-package
+
+    environment: release
+
+    permissions:
+      id-token: write
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Set up Python
+        uses: actions/setup-python@v4
+        with:
+          python-version: '3.x'
+
+      - name: Download package artifact
+        uses: actions/download-artifact@v4
+        with:
+          name: package
+          path: dist
+
+      - name: Publish package
+        uses: pypa/gh-action-pypi-publish@release/v1