specs/debug.py

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'''Debugging utilities.'''


import sys
import traceback
import inspect


def excepthook(type, value, tb):
	"""
	Automatically start the debugger on an exception.

	See also:
	- http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/65287
	"""

	if hasattr(sys, 'ps1') \
	or not (sys.stdin.isatty() and sys.stdout.isatty() and sys.stderr.isatty()) \
	or type == SyntaxError or type == KeyboardInterrupt:
		# we are in interactive mode or we don't have a tty-like
		# device, so we call the default hook
		oldexcepthook(type, value, tb)
	else:
		import traceback, pdb
		# we are NOT in interactive mode, print the exception...
		traceback.print_exception(type, value, tb)
		print()
		# ...then start the debugger in post-mortem mode.
		pdb.pm()

oldexcepthook, sys.excepthook = sys.excepthook, excepthook


def dump(var):
	sys.stderr.write(repr(var) + '\n')