Decorators based BDD testing

Differs from mainstream BDD by extended stages set - given-when-then-should

@when

• may raise ScenarioPreconditionsNotMet to skip tests
• may return list of Behaviour objects to start subtests

Main purpose is to experiment with testing of tree structures (DOM for example) with tree of tests

An example:

from bdd import Behaviour
class TestSub(Behaviour):
    @given
    def number(self, n):
        return n
    @should
    def be_equal_to_5(self, n):
        return n==5

class TestOfTest(Behaviour):
    @given
    def some_string(self, a):
        return a
    @when
    def string_is_testArg(self, a):
        assert a == 'testarg'

    @should
    def len_string_equal_to_7(self, a):
        return len(a) == 7

    @when
    def all_is_good(self, a):
        return TestSub(5), TestSub(6)    
    @should
    def be_equal_ToTestarg(self, a):
        return a == 'testarg'            

    @should
    def len_string_equal_to_7a(self, a):
        return len(a) == 7

TODO

1. Integrate with unittest.TestCase test run
2. Integrate with TestCase result formatter
3. Enable TestCase subclassing with Behaviour.

Smth like:

from bdd import TestCaseBehaviour
from django.test import LiveServerTestCase
class LivePageTestCase(TestCaseBehaviour(LiveServerTestCase)):
    pass