fixup! Add an sdist test inclusion smoke test

.github/workflows/ci.yml

@@ -78,6 +78,64 @@ jobs:
             dist/${{ steps.artifact-name.outputs.wheel }}
           retention-days: 5
 
+      - name: >-
+          Smoke-test:
+          retrieve the project source from an sdist inside the GHA artifact
+        uses: re-actors/checkout-python-sdist@release/v2
+        with:
+          source-tarball-name: ${{ steps.artifact-name.outputs.sdist }}
+          workflow-artifact-name: ${{ env.dists-artifact-name }}
+
+      - name: >-
+          Smoke-test: move the sdist-retrieved dir into sdist-src
+        run: |
+          mv -v '${{ github.workspace }}' '${{ runner.temp }}/sdist-src'
+          mkdir -pv '${{ github.workspace }}'
+          mv -v '${{ runner.temp }}/sdist-src' '${{ github.workspace }}/sdist-src'
+        shell: bash -eEuo pipefail {0}
+
+      - name: >-
+          Smoke-test: grab the source from Git into git-src
+        uses: actions/checkout@v4
+        with:
+          path: git-src
+
+      - name: >-
+          Smoke-test: install test requirements from the Git repo
+        run: >-
+          python -Im
+          pip install -c test-requirements.txt -r test-requirements.txt
+        shell: bash -eEuo pipefail {0}
+        working-directory: git-src
+
+      - name: >-
+          Smoke-test: collect tests from the Git repo
+        env:
+          PYTHONPATH: src/
+        run: >-
+          pytest --collect-only -qq .
+          | sort
+          | tee collected-tests
+        shell: bash -eEuo pipefail {0}
+        working-directory: git-src
+
+      - name: >-
+          Smoke-test: collect tests from the sdist tarball
+        env:
+          PYTHONPATH: src/
+        run: >-
+          pytest --collect-only -qq .
+          | sort
+          | tee collected-tests
+        shell: bash -eEuo pipefail {0}
+        working-directory: sdist-src
+
+      - name: >-
+          Smoke-test:
+          verify that all the tests from Git are included in the sdist
+        run: diff --unified sdist-src/collected-tests git-src/collected-tests
+        shell: bash -eEuo pipefail {0}
+
   Windows:
     name: 'Windows (${{ matrix.python }}, ${{ matrix.arch }}${{ matrix.extra_name }})'
     needs: