import sys, time, os

from django.conf import settings

from django.core import mail

from django.core.mail.backends import locmem

from django.test import signals

from django.template import Template

from django.utils.translation import deactivate

class ContextList(list):

    """A wrapper that provides direct key access to context items contained

    in a list of context objects.

    """

    def __getitem__(self, key):

        if isinstance(key, basestring):

            for subcontext in self:

                if key in subcontext:

                    return subcontext[key]

            raise KeyError(key)

        else:

            return super(ContextList, self).__getitem__(key)

def instrumented_test_render(self, context):

    """

    An instrumented Template render method, providing a signal

    that can be intercepted by the test system Client

    """

    signals.template_rendered.send(sender=self, template=self, context=context)

    return self.nodelist.render(context)

def setup_test_environment():

    """Perform any global pre-test setup. This involves:

        - Installing the instrumented test renderer

        - Set the email backend to the locmem email backend.

        - Setting the active locale to match the LANGUAGE_CODE setting.

    """

    Template.original_render = Template._render

    Template._render = instrumented_test_render

    mail.original_SMTPConnection = mail.SMTPConnection

    mail.SMTPConnection = locmem.EmailBackend

    mail.original_email_backend = settings.EMAIL_BACKEND

    settings.EMAIL_BACKEND = 'django.core.mail.backends.locmem.EmailBackend'

    mail.outbox = []

    deactivate()

def teardown_test_environment():

    """Perform any global post-test teardown. This involves:

        - Restoring the original test renderer

        - Restoring the email sending functions

    """

    Template._render = Template.original_render

    del Template.original_render

    mail.SMTPConnection = mail.original_SMTPConnection

    del mail.original_SMTPConnection

    settings.EMAIL_BACKEND = mail.original_email_backend

    del mail.original_email_backend

    del mail.outbox

def get_runner(settings):

    test_path = settings.TEST_RUNNER.split('.')

    # Allow for Python 2.5 relative paths

    if len(test_path) > 1:

        test_module_name = '.'.join(test_path[:-1])

    else:

        test_module_name = '.'

    test_module = __import__(test_module_name, {}, {}, test_path[-1])

    test_runner = getattr(test_module, test_path[-1])

    return test_runner