Add --diff flag to Black for easier debugging (#219)

diff --git a/noxfile.py b/noxfile.py
index bd74a2b25ae203fff99017bd0cdb8bb616753b31..739470ab99cf68156d171f1935fa9a38f11995b4 100644 (file)
--- a/noxfile.py
+++ b/noxfile.py
@@ -21,7 +21,7 @@ def check(session):
         "black", "flake8", "flake8-bugbear", "flake8-comprehensions", "mypy"
     )
 
-    session.run("black", "--check", "--target-version=py36", *source_files)
+    session.run("black", "--check", "--diff", "--target-version=py36", *source_files)
     session.run("flake8", *source_files)
     session.run("mypy", "httpx")