Mini Shell

##############################################################################
#
# Copyright (c) 2003 Zope Foundation and Contributors.
# All Rights Reserved.
#
# This software is subject to the provisions of the Zope Public License,
# Version 2.1 (ZPL).  A copy of the ZPL should accompany this distribution.
# THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
# WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
# FOR A PARTICULAR PURPOSE.
#
##############################################################################
"""Tests for advice

This module was adapted from 'protocols.tests.advice', part of the Python
Enterprise Application Kit (PEAK).  Please notify the PEAK authors
(pje@telecommunity.com and tsarna@sarna.org) if bugs are found or
Zope-specific changes are required, so that the PEAK version of this module
can be kept in sync.

PEAK is a Python application framework that interoperates with (but does
not require) Zope 3 and Twisted.  It provides tools for manipulating UML
models, object-relational persistence, aspect-oriented programming, and more.
Visit the PEAK home page at http://peak.telecommunity.com for more information.
"""

import sys
import unittest


class FrameInfoTest(unittest.TestCase):

    def test_w_module(self):
        from zope.interface.tests import advisory_testing
        (kind, module,
         f_locals, f_globals) = advisory_testing.moduleLevelFrameInfo
        self.assertEqual(kind, "module")
        for d in module.__dict__, f_locals, f_globals:
            self.assertIs(d, advisory_testing.my_globals)

    def test_w_class(self):
        from zope.interface.tests import advisory_testing
        (kind,
         module,
         f_locals,
         f_globals) = advisory_testing.NewStyleClass.classLevelFrameInfo
        self.assertEqual(kind, "class")

        for d in module.__dict__, f_globals:
            self.assertIs(d, advisory_testing.my_globals)

    def test_inside_function_call(self):
        from zope.interface.advice import getFrameInfo
        kind, module, f_locals, f_globals = getFrameInfo(sys._getframe())
        self.assertEqual(kind, "function call")

        frame = sys._getframe()
        self.assertEqual(f_locals, frame.f_locals)
        self.assertEqual(f_locals, locals())

        for d in module.__dict__, f_globals:
            self.assertIs(d, globals())

    def test_inside_exec(self):
        from zope.interface.advice import getFrameInfo
        _globals = {'getFrameInfo': getFrameInfo}
        _locals = {}
        exec(_FUNKY_EXEC, _globals, _locals)
        self.assertEqual(_locals['kind'], "exec")
        self.assertIs(_locals['f_locals'], _locals)
        self.assertIsNone(_locals['module'])
        self.assertIs(_locals['f_globals'], _globals)


_FUNKY_EXEC = """\
import sys
kind, module, f_locals, f_globals = getFrameInfo(sys._getframe())
"""


class Test_isClassAdvisor(unittest.TestCase):

    def _callFUT(self, *args, **kw):
        from zope.interface.advice import isClassAdvisor
        return isClassAdvisor(*args, **kw)

    def test_w_non_function(self):
        self.assertEqual(self._callFUT(self), False)

    def test_w_normal_function(self):

        def foo():
            raise NotImplementedError()

        self.assertEqual(self._callFUT(foo), False)

    def test_w_advisor_function(self):

        def bar():
            raise NotImplementedError()

        bar.previousMetaclass = object()
        self.assertEqual(self._callFUT(bar), True)


class Test_determineMetaclass(unittest.TestCase):

    def _callFUT(self, *args, **kw):
        from zope.interface.advice import determineMetaclass
        return determineMetaclass(*args, **kw)

    def test_empty_w_explicit_metatype(self):

        class Meta(type):
            pass

        self.assertEqual(self._callFUT((), Meta), Meta)

    def test_single(self):

        class Meta(type):
            pass

        self.assertEqual(self._callFUT((Meta,)), type)

    def test_meta_of_class(self):

        class Metameta(type):
            pass

        class Meta(type, metaclass=Metameta):
            pass

        self.assertEqual(self._callFUT((Meta, type)), Metameta)

    def test_multiple_in_hierarchy_py3k(self):

        class Meta_A(type):
            pass

        class Meta_B(Meta_A):
            pass

        class A(type, metaclass=Meta_A):
            pass

        class B(type, metaclass=Meta_B):
            pass

        self.assertEqual(self._callFUT((A, B)), Meta_B)

    def test_multiple_not_in_hierarchy_py3k(self):

        class Meta_A(type):
            pass

        class Meta_B(type):
            pass

        class A(type, metaclass=Meta_A):
            pass

        class B(type, metaclass=Meta_B):
            pass

        self.assertRaises(TypeError, self._callFUT, (A, B))


class Test_minimalBases(unittest.TestCase):

    def _callFUT(self, klasses):
        from zope.interface.advice import minimalBases
        return minimalBases(klasses)

    def test_empty(self):
        self.assertEqual(self._callFUT([]), [])

    def test_w_newstyle_meta(self):
        self.assertEqual(self._callFUT([type]), [type])

    def test_w_newstyle_class(self):

        class C:
            pass

        self.assertEqual(self._callFUT([C]), [C])

    def test_simple_hierarchy_skips_implied(self):

        class A:
            pass

        class B(A):
            pass

        class C(B):
            pass

        class D:
            pass

        self.assertEqual(self._callFUT([A, B, C]), [C])
        self.assertEqual(self._callFUT([A, C]), [C])
        self.assertEqual(self._callFUT([B, C]), [C])
        self.assertEqual(self._callFUT([A, B]), [B])
        self.assertEqual(self._callFUT([D, B, D]), [B, D])

    def test_repeats_kicked_to_end_of_queue(self):

        class A:
            pass

        class B:
            pass

        self.assertEqual(self._callFUT([A, B, A]), [B, A])