Convert bytes to string even for the empty case
If we don't convert, the later `format` will coerce to the literal
`b''`.  We don't want that but `''` (t.i. nothing) in the message.
@@ -212,8 +212,8 @@ def check_output(cmd, cwd=None):
except Exception as err:
import textwrap
output_ = getattr(err, 'output', '')
- if output_:
output_ = process_popen_output(output_)
+ if output_:
output_ = textwrap.indent(output_, ' ')
output_ = "\n ...\n{}".format(output_)
logger.warning(
