Add code coverage

* Use coverage to generate the XML and report it with codecov

* Add badge showing users code coverage at the top of the README

Author: tomice

.github/workflows/ci.yml

@@ -27,7 +27,7 @@ jobs:
     - name: Install dependencies
       run: |
         python -m pip install --upgrade pip
-        pip install ruff black
+        pip install ruff black coverage codecov
 
     - name: Lint with Ruff
       run: |
@@ -37,7 +37,13 @@ jobs:
       run: |
         black --check git_py_stats
 
-    - name: Run tests
+    - name: Run tests with coverage
       run: |
-        python -m unittest discover -s git_py_stats/tests
+        coverage run -m unittest discover -s git_py_stats/tests
+        coverage xml
 
+    - name: Upload coverage to Codecov
+      uses: codecov/codecov-action@v4
+      with:
+        token: ${{ secrets.CODECOV_TOKEN }}
+        file: coverage.xml

README.md

@@ -3,6 +3,7 @@
 <div align="center">
 
 [![CI](https://github.com/tomice/git-py-stats/workflows/CI/badge.svg)](https://github.com/tomice/git-py-stats/actions)
+[![codecov](https://codecov.io/gh/tomice/git-py-stats/branch/main/graph/badge.svg)](https://codecov.io/gh/tomice/git-py-stats)
 [![Ruff](https://img.shields.io/badge/linting-Ruff-green?logo=ruff)](https://docs.astral.sh/ruff/)
 [![Black](https://img.shields.io/badge/code%20style-Black-000000.svg?logo=black)](https://black.readthedocs.io/en/stable/)
 [![License: MIT](https://img.shields.io/badge/License-MIT-blue.svg)](LICENSE)