Support skipping AST printing on test failure

diff --git a/tests/test_black.py b/tests/test_black.py
index 7dba611141c099e9054421f55bd371ac242fced3..ec7a883b5b3291054b500f6f938c5595c68c3910 100644 (file)
--- a/tests/test_black.py
+++ b/tests/test_black.py
@@ -1,6 +1,7 @@
 #!/usr/bin/env python3
 from functools import partial
 from io import StringIO
+import os
 from pathlib import Path
 import sys
 from typing import Any, List, Tuple
@@ -47,7 +48,7 @@ class BlackTestCase(unittest.TestCase):
     maxDiff = None
 
     def assertFormatEqual(self, expected: str, actual: str) -> None:
-        if actual != expected:
+        if actual != expected and not os.environ.get('SKIP_AST_PRINT'):
             bdv: black.DebugVisitor[Any]
             black.out('Expected tree:', fg='green')
             try: