Add codecov (#16)

* Add coverage to Makefile

* Add coverage to tests workflow

* Add .codecov.yml

* Configure action

* Add codecov badge to README

* Require diff changes, remove unittest tag

Author: eigenfoo

.codecov.yml

@@ -0,0 +1,20 @@
+codecov:
+  require_ci_to_pass: yes
+
+coverage:
+  precision: 2
+  round: down
+  range: "70...100"
+
+  status:
+    project: yes
+    patch: yes
+    changes: no
+
+comment:
+  layout: "reach, diff, flags, files"
+  behavior: default
+  require_changes: true   # if true: only post the comment if coverage changes
+  require_base: no        # [yes :: must have a base report to post]
+  require_head: yes       # [yes :: must have a head report to post]
+  branches: null          # branch names that can post comment

.github/workflows/tests.yml

@@ -22,5 +22,14 @@ jobs:
         python -m pip install --upgrade pip
         pip install -r requirements.txt
         pip install -r requirements-dev.txt
-    - name: pytest
+    - name: Run tests and generate reports
       run: make test
+    - name: Upload coverage to Codecov
+      uses: codecov/codecov-action@v1
+      if: matrix.python-version == 3.7
+      with:
+        token: ${{ secrets.CODECOV_TOKEN }}
+        file: ./coverage.xml
+        name: codecov-umbrella
+        yml: ./.codecov.yml
+        fail_ci_if_error: true

Makefile

@@ -69,7 +69,7 @@ black:  # Format code in-place using black.
 
 .PHONY: test
 test:  # Test code using pytest.
-	pytest -v littlemcmc tests --doctest-modules --html=testing-report.html --self-contained-html
+	pytest -v littlemcmc tests --doctest-modules --html=testing-report.html --self-contained-html --cov=./ --cov-report=xml
 
 .PHONY: lint
 lint: blackstyle pylintstyle pydocstyle mypytypes  # Lint code using black, pylint, pydocstyle and mypy.
@@ -79,7 +79,7 @@ check: lint test  # Both lint and test code. Runs `make lint` followed by `make
 
 .PHONY: clean
 clean:  # Clean project directories.
-	rm -rf dist/ site/ littlemcmc.egg-info/ pip-wheel-metadata/ __pycache__/ testing-report.html
+	rm -rf dist/ site/ littlemcmc.egg-info/ pip-wheel-metadata/ __pycache__/ coverage.xml
 	find littlemcmc/ tests/ -type d -name "__pycache__" -exec rm -rf {} +
 	find littlemcmc/ tests/ -type d -name "__pycache__" -delete
 	find littlemcmc/ tests/ -type f -name "*.pyc" -delete

README.md

@@ -2,7 +2,8 @@
 
 ![Tests Status](https://github.com/eigenfoo/littlemcmc/workflows/tests/badge.svg)
 ![Lint Status](https://github.com/eigenfoo/littlemcmc/workflows/lint/badge.svg)
-![License](https://img.shields.io/github/license/eigenfoo/littlemcmc)
+[![Coverage Status](https://codecov.io/gh/eigenfoo/littlemcmc/branch/master/graph/badge.svg)](https://codecov.io/gh/eigenfoo/littlemcmc)
+[![License](https://img.shields.io/github/license/eigenfoo/littlemcmc)](https://github.com/eigenfoo/littlemcmc/blob/master/LICENSE.littlemcmc.txt)
 
 > littlemcmc     /lɪtəl ɛm si ɛm si/     _noun_
 >