Run black with `--diff` to show what is wrong

Closes #1803
4 years ago · 0cac0bc761
1 changed files with 1 additions and 0 deletions
--- a/.github/workflows/black.yml
+++ b/.github/workflows/black.yml
@ -19,3 +19,4 @@ jobs:
            --line-length=120
            --target-version=py36
            --check
+            --diff