I got annoyed the other day when I kept editing mission critical json based config files and had no way of knowing if the files were syntactically correct.

test_json.py

#!/usr/bin/env python

import json
import sys

checkedfiles={'good':[], 'bad':[]}

if len(sys.argv) > 1:
	for arg in sys.argv[1:]:
		try:
			data = json.load(open(arg))
			checkedfiles['good'].append(arg)
		except:
			checkedfiles['bad'].append(arg)
	
	print "%d OK: %s" % ( len(checkedfiles['good']) , ",".join(checkedfiles['good']) )
	print "%d BAD: %s" % ( len(checkedfiles['bad']) , ",".join(checkedfiles['bad']) )

print "Checked total of %d files." % len(sys.argv[1:])
print "---"