ci: generate a code coverage badge (using coveralls.io)

.github/workflows/validate-code.yaml

@@ -7,7 +7,7 @@
 name: verify pull request
 
 on:
-  push:
+  pull_request:
 
 # our tox configuration leverages pyenv to test on multiple Python versions.
 # It is unclear if we can leverage actions/setup-python@v4 to do the same.
@@ -68,6 +68,16 @@ jobs:
           if [[ -n $CONTRIB_FILES ]] ; then
             pdm run mypy $CONTRIB_FILES
           fi
+      - name: generate coverage report
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: |
+          pdm run coverage run --source=feeph.i2c -m pytest tests/
+          pdm run coveralls
+          mkdir -p coverage
+          pdm run coverage-lcov --output_file_path=coverage/lcov.info
+      - name: coveralls action
+        uses: coverallsapp/github-action@v2
   test:
     name: perform unit tests
     # wait on linting results; makes no sense to test if the code is broken

README.md

@@ -2,6 +2,7 @@
 
 [![Copier](https://img.shields.io/endpoint?url=https://raw.githubusercontent.com/copier-org/copier/master/img/badge/badge-grayscale-inverted-border-purple.json)](https://github.com/copier-org/copier)
 [![pre-commit](https://img.shields.io/badge/pre--commit-enabled-brightgreen?logo=pre-commit)](https://github.com/pre-commit/pre-commit)
+[![Coverage Status](https://coveralls.io/repos/github/feeph/libi2c-python/badge.svg)](https://coveralls.io/github/feeph/libi2c-python)
 [![pdm-managed](https://img.shields.io/endpoint?url=https%3A%2F%2Fcdn.jsdelivr.net%2Fgh%2Fpdm-project%2F.github%2Fbadge.json)](https://pdm-project.org)
 [![tox](https://img.shields.io/badge/tox-ab79d2)](https://tox.wiki/)
 

pyproject.toml

@@ -100,6 +100,7 @@ tools = [
     "autopep8      ~= 2.2",
     "copier        ~= 9.3",
     "coverage-lcov ~= 0.3",
+    "coveralls     ~= 4.0",
     "flake8        ~= 7.0",
     "mypy          ~= 1.10",
     "pylint        ~= 3.2",