"""General utilities for working with subprocesses.""" import signal import subprocess from subprocess import PIPE # noqa: F401 __all__ = ["PIPE", "CalledProcessError", "check_output"] class CalledProcessError(subprocess.CalledProcessError): """Add stdout,stderr to str representation""" def __str__(self): if self.returncode and self.returncode < 0: try: return "Command '%s' died with %r.\nStdout: %s\nStderr: %s" % ( self.cmd, signal.Signals( -self.returncode ), # noqa E501 pylint: disable=E1101 self.stdout, self.stderr, ) except ValueError: return ( "Command '%s' died with unknown signal %d." "\nStdout: %s\nStderr: %s" % (self.cmd, -self.returncode, self.stdout, self.stderr) ) else: return ( "Command '%s' returned non-zero exit status %d." "\nStdout: %s\nStderr: %s" % (self.cmd, self.returncode, self.stdout, self.stderr) ) def check_output(*args, **kwargs): """A wrapper for stdlib subprocess.check_output. Include stdout/stderr in error message. """ try: return subprocess.check_output(*args, **kwargs) except subprocess.CalledProcessError as e: raise CalledProcessError( e.returncode, e.cmd, e.stdout, e.stderr ) from None