Add diff-cover check to Github Actions CI. Closes jaraco/skeleton#90.

Author: jaraco

.github/workflows/main.yml

@@ -53,6 +53,24 @@ jobs:
       - name: Run
         run: tox
 
+  diffcov:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+        with:
+          fetch-depth: 0
+      - name: Setup Python
+        uses: actions/setup-python@v4
+        with:
+          python-version: 3.x
+      - name: Install tox
+        run: |
+          python -m pip install tox
+      - name: Evaluate coverage
+        run: tox
+        env:
+          TOXENV: diffcov
+
   docs:
     runs-on: ubuntu-latest
     env:

tox.ini

@@ -8,6 +8,14 @@ usedevelop = True
 extras =
 	testing
 
+[testenv:diffcov]
+deps =
+	diff-cover
+commands =
+	pytest {posargs} --cov-report xml
+	diff-cover coverage.xml --compare-branch=origin/main --html-report diffcov.html
+	diff-cover coverage.xml --compare-branch=origin/main --fail-under=100
+
 [testenv:docs]
 extras =
 	docs