make test_support's captured_output a bit more robust when exceptions happen

diff --git a/Lib/test/test_support.py b/Lib/test/test_support.py
index 6f739af3fb2cab410eb2c9c0e2985971a14e2e20..04a0ab85740081b117ca6bddbc7ab8971cb97b2d 100644 (file)
--- a/Lib/test/test_support.py
+++ b/Lib/test/test_support.py
@@ -482,8 +482,10 @@ def captured_output(stream_name):
     import StringIO
     orig_stdout = getattr(sys, stream_name)
     setattr(sys, stream_name, StringIO.StringIO())
-    yield getattr(sys, stream_name)
-    setattr(sys, stream_name, orig_stdout)
+    try:
+        yield getattr(sys, stream_name)
+    finally:
+        setattr(sys, stream_name, orig_stdout)
 
 def captured_stdout():
     return captured_output("stdout")