import os
import sys
import unittest
from cStringIO import StringIO
from optparse import OptionParser
import nose.core
from nose.config import Config
from nose.tools import set_trace
from mock import Bucket, MockOptParser


class NullLoader:
    def loadTestsFromNames(self, names):
        return unittest.TestSuite()

class TestAPI_run(unittest.TestCase):

    def test_restore_stdout(self):
        print "AHOY"
        s = StringIO()
        print s
        stdout = sys.stdout
        conf = Config(stream=s)
        # set_trace()
        print "About to run"
        res = nose.core.run(
            testLoader=NullLoader(), argv=['test_run'], env={}, config=conf)
        print "Done running"
        stdout_after = sys.stdout
        self.assertEqual(stdout, stdout_after)

class Undefined(object):
    pass

class TestUsage(unittest.TestCase):
    
    def test_from_directory(self):
        usage_txt = nose.core.TestProgram.usage()
        assert usage_txt.startswith('nose collects tests automatically'), (
                "Unexpected usage: '%s...'" % usage_txt[0:50].replace("\n", '\n'))
    
    def test_from_zip(self):
        requested_data = []
        
        # simulates importing nose from a zip archive
        # with a zipimport.zipimporter instance
        class fake_zipimporter(object):
            
            prefix = ''
            zipfile = '<fake zipfile>'
            
            def get_data(self, path):
                requested_data.append(path)
                return "<usage>"
                    
        existing_loader = getattr(nose, '__loader__', Undefined)
        try:
            nose.__loader__ = fake_zipimporter()
            usage_txt = nose.core.TestProgram.usage()
            self.assertEqual(usage_txt, '<usage>')
            self.assertEqual(requested_data, ['nose%susage.txt' % os.sep])
        finally:
            if existing_loader is not Undefined:
                nose.__loader__ = existing_loader
            else:
                del nose.__loader__
    
    def test_from_zip_with_prefix(self):
        requested_data = []
        
        # simulates importing nose from a zip archive
        # with a zipimport.zipimporter instance
        class fake_zipimporter(object):
            
            prefix = 'PREFIX'
            zipfile = '<fake zipfile>'
            
            def get_data(self, path):
                requested_data.append(path)
                return "<usage>"
                
        existing_loader = getattr(nose, '__loader__', Undefined)
        try:            
            nose.__loader__ = fake_zipimporter()
            usage_txt = nose.core.TestProgram.usage()
            self.assertEqual(usage_txt, '<usage>')
            self.assertEqual(requested_data, 
                             ['PREFIX%snose%susage.txt' % (os.sep, os.sep)])
        finally:
            if existing_loader is not Undefined:
                nose.__loader__ = existing_loader
            else:
                del nose.__loader__
        
if __name__ == '__main__':
    unittest.main()