fix

.github/workflows/ci.yml

@@ -47,7 +47,7 @@ jobs:
         apt-get update && apt-get install -y build-essential
         python -m pip install --upgrade pip
         pip install --no-build-isolation .[test]
-        pip install coverage
+        python setup.py build_ext --inplace
     - name: Run tests
       run: make unittest
     - name: coverage