diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 38b62995..8d916e49 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -34,6 +34,5 @@ jobs:
         cog --check docs/*.rst
     - name: Check if blacken-docs needs to be run
       run: |
+        # This fails on syntax errors, or a diff was applied
         blacken-docs -l 60 docs/*.rst
-        # This fails if a diff was generated:
-        git diff-index --quiet HEAD --
diff --git a/docs/testing_plugins.rst b/docs/testing_plugins.rst
index 6361d744..1bbaaac1 100644
--- a/docs/testing_plugins.rst
+++ b/docs/testing_plugins.rst
@@ -118,7 +118,9 @@ Here's an example that uses the `sqlite-utils library <https://sqlite-utils.data
 
     @pytest.mark.asyncio
     async def test_example_table_json(datasette):
-        response = await datasette.client.get("/test/dogs.json?_shape=array")
+        response = await datasette.client.get(
+            "/test/dogs.json?_shape=array"
+        )
         assert response.status_code == 200
         assert response.json() == [
             {"id": 1, "name": "Cleo", "age": 5},