test_copy_traits.py

#  Copyright (c) 2007, Enthought, Inc.
#  All rights reserved.
#
#  This software is provided without warranty under the terms of the BSD
#  license included in /LICENSE.txt and may be redistributed only
#  under the conditions described in the aforementioned license.  The license
#  is also available online at http://www.enthought.com/licenses/BSD.txt

from __future__ import absolute_import

from traits.testing.unittest_tools import unittest

from ..api import HasTraits, Instance, Str


class Shared(HasTraits):
    s = Str('new instance of Shared')


class Foo(HasTraits):
    s = Str('new instance of Foo')
    shared = Instance(Shared)


class Bar(HasTraits):
    s = Str('new instance of Bar')
    foo = Instance(Foo)
    shared = Instance(Shared)


class Baz(HasTraits):
    s = Str('new instance of Baz')
    bar = Instance(Bar)
    shared = Instance(Shared)


class CopyTraitsBase(unittest.TestCase):
    """ Validate that copy_traits
    """
    __test__ = False

    def setUp(self):
        print '\n**CopyTraitsBase.setUp ',
        super(CopyTraitsBase, self).setUp()
        self.shared = Shared(s='shared')
        self.foo = Foo(shared=self.shared, s='foo')
        self.bar = Bar(shared=self.shared, foo=self.foo, s='bar')
        self.baz = Baz(shared=self.shared, bar=self.bar, s='baz')

        self.shared2 = Shared(s='shared2')
        self.foo2 = Foo(shared=self.shared2, s='foo2')
        self.bar2 = Bar(shared=self.shared2, foo=self.foo2, s='bar2')
        self.baz2 = Baz(shared=self.shared2, bar=self.bar2, s='baz2')

        return

    def print_copy(self):
        print '\nfoo.copy:', self.foo.base_trait('shared').copy
        print 'bar.copy:', self.bar.base_trait('shared').copy
        print 'baz.copy:', self.baz.base_trait('shared').copy
        print 'foo2.copy:', self.foo2.base_trait('shared').copy
        print 'bar2.copy:', self.bar2.base_trait('shared').copy
        print 'baz2.copy:', self.baz2.base_trait('shared').copy

    def set_shared_copy(self, value):
        """ Change the copy style for the 'shared' traits. """
        #self.print_copy()
        self.foo.base_trait('shared').copy = value
        self.bar.base_trait('shared').copy = value
        self.baz.base_trait('shared').copy = value

        # copy is metadata and therefore a shared  a class attribute
        # self.foo2.base_trait('shared').copy = value
        # self.bar2.base_trait('shared').copy = value
        # self.baz2.base_trait('shared').copy = value
        #self.print_copy()


class TestCopyTraitsSetup(CopyTraitsBase):
    __test__ = True

    def setUp(self):
        super(TestCopyTraitsSetup, self).setUp()
        print '\nshared', self.shared
        print 'foo', self.foo
        print 'bar', self.bar
        print 'baz', self.baz
        print '\nshared2', self.shared2
        print 'foo2', self.foo2
        print 'bar2', self.bar2
        print 'baz2', self.baz2

        return

    def test_setup(self):
        self.assertIs(self.foo, self.bar.foo)
        self.assertIs(self.bar, self.baz.bar)
        self.assertIs(self.foo.shared, self.shared)
        self.assertIs(self.bar.shared, self.shared)
        self.assertIs(self.baz.shared, self.shared)

        self.assertIs(self.foo2, self.bar2.foo)
        self.assertIs(self.bar2, self.baz2.bar)
        self.assertIs(self.foo2.shared, self.shared2)
        self.assertIs(self.bar2.shared, self.shared2)
        self.assertIs(self.baz2.shared, self.shared2)
        return


class CopyTraits:

    def test_baz2_s(self):
        self.assertEqual(self.baz2.s, 'baz')
        self.assertEqual(self.baz2.s, self.baz.s)

    def test_baz2_bar_s(self):
        self.assertEqual(self.baz2.bar.s, 'bar')
        self.assertEqual(self.baz2.bar.s, self.baz.bar.s)

    def test_baz2_bar_foo_s(self):
        self.assertEqual(self.baz2.bar.foo.s, 'foo')
        self.assertEqual(self.baz2.bar.foo.s, self.baz.bar.foo.s)

    def test_baz2_shared_s(self):
        self.assertEqual(self.baz2.shared.s, 'shared')
        self.assertEqual(self.baz2.bar.shared.s, 'shared')
        self.assertEqual(self.baz2.bar.foo.shared.s, 'shared')

    def test_baz2_bar(self):
        # First hand Instance trait is different and
        # is not the same object as the source.

        self.assertIsNot(self.baz2.bar, None)
        self.assertIsNot(self.baz2.bar, self.bar2)
        self.assertIsNot(self.baz2.bar, self.baz.bar)

    def test_baz2_bar_foo(self):
        # Second hand Instance trait is a different object and
        # is not the same object as the source.

        self.assertIsNot(self.baz2.bar.foo, None)
        self.assertIsNot(self.baz2.bar.foo, self.foo2)
        self.assertIsNot(self.baz2.bar.foo, self.baz.bar.foo)


class CopyTraitsSharedCopyNone:
    def test_baz2_shared(self):
        # First hand Instance trait is a different object and
        # is not the same object as the source.

        self.assertIsNot(self.baz2.shared, None)
        self.assertIsNot(self.baz2.shared, self.shared2)
        self.assertIsNot(self.baz2.shared, self.shared)

    def test_baz2_bar_shared(self):
        # Second hand Instance that was shared is a different object and
        # not the same object as the source and
        # not the same object as the new first hand instance that was the same.
        # I.e. There are now (at least) two copies of one original object.

        self.assertIsNot(self.baz2.bar.shared, None)
        self.assertIsNot(self.baz2.bar.shared, self.shared2)
        self.assertIsNot(self.baz2.bar.shared, self.shared)
        self.assertIsNot(self.baz2.bar.shared, self.baz2.shared)

    def test_baz2_bar_foo_shared(self):
        # Third hand Instance that was shared is a different object and
        # not the same object as the source and
        # not the same object as the new first hand instance that was the same.
        # I.e. There are now (at least) two copies of one original object.

        self.assertIsNot(self.baz2.bar.foo.shared, None)
        self.assertIsNot(self.baz2.bar.foo.shared, self.shared2)
        self.assertIsNot(self.baz2.bar.foo.shared, self.shared)
        self.assertIsNot(self.baz2.bar.foo.shared, self.baz2.shared)

    def test_baz2_bar_and_foo_shared(self):
        #
        # THE BEHAVIOR DEMONSTRATED BY THIS TEST CASE DOES NOT SEEM TO BE
        # CORRECT.
        #
        # Second and Third hand Instance object that was shared with first hand
        # instance are the same as each other but
        # Every reference to the same original object has been replace by
        # a reference to the same copy of the same source object except the
        # first hand reference which is a different copy.
        # I.e. The shared relationship has been fubarred by copy_traits: it's
        # not maintained, but not completely destroyed.
        self.assertIs(self.baz2.bar.shared, self.baz2.bar.foo.shared)
        self.assertIsNot(self.baz2.shared, self.baz2.bar.foo.shared)


class TestCopyTraitsSharedCopyNone(CopyTraits,
                                   CopyTraitsSharedCopyNone):
    __test__ = False

    def setUp(self):
        print '\n***TestCopyTraitsSharedCopyNone',
        #super(TestCopyTraitsSharedCopyNone,self).setUp()

        # deep is the default value for Instance trait copy
        self.set_shared_copy('deep')
        return


class TestCopyTraitsCopyNotSpecified(CopyTraitsBase,
                                     TestCopyTraitsSharedCopyNone):
    __test__ = True

    def setUp(self):
        print '\n*TestCopyTraitsCopyNotSpecified',
#        super(TestCopyTraitsCopyNotSpecified,self).setUp()
        CopyTraitsBase.setUp(self)
        TestCopyTraitsSharedCopyNone.setUp(self)
        self.baz2.copy_traits(self.baz)
        return


class TestCopyTraitsCopyShallow(CopyTraitsBase, TestCopyTraitsSharedCopyNone):
    __test__ = True

    def setUp(self):
        print '\n*TestCopyTraitsCopyShallow',
#        super(TestCopyTraitsCopyShallow,self).setUp()
        CopyTraitsBase.setUp(self)
        TestCopyTraitsSharedCopyNone.setUp(self)
        self.baz2.copy_traits(self.baz, copy='shallow')
        return


class TestCopyTraitsCopyDeep(CopyTraitsBase, TestCopyTraitsSharedCopyNone):
    __test__ = True

    def setUp(self):
        print '\n*TestCopyTraitsCopyDeep',
#        super(TestCopyTraitsCopyDeep,self).setUp()
        CopyTraitsBase.setUp(self)
        TestCopyTraitsSharedCopyNone.setUp(self)
        self.baz2.copy_traits(self.baz, copy='deep')
        return


class CopyTraitsSharedCopyRef:
    def test_baz2_shared(self):
        # First hand Instance trait is a different object and
        # is the same object as the source.

        self.assertIsNot(self.baz2.shared, None)
        self.assertIsNot(self.baz2.shared, self.shared2)
        self.assertIs(self.baz2.shared, self.shared)

    def test_baz2_bar_shared(self):
        self.assertIsNot(self.baz2.bar.shared, None)
        self.assertIsNot(self.baz2.bar.shared, self.shared2)
        self.assertIs(self.baz2.bar.shared, self.shared)
        self.assertIs(self.baz2.bar.shared, self.baz2.shared)

    def test_baz2_bar_foo_shared(self):
        self.assertIsNot(self.baz2.bar.foo.shared, None)
        self.assertIsNot(self.baz2.bar.foo.shared, self.shared2)
        self.assertIs(self.baz2.bar.foo.shared, self.shared)
        self.assertIs(self.baz2.bar.foo.shared, self.baz2.shared)

    def test_baz2_bar_and_foo_shared(self):
        self.assertIs(self.baz2.bar.shared, self.baz2.bar.foo.shared)
        self.assertIs(self.baz2.shared, self.baz2.bar.foo.shared)


class TestCopyTraitsSharedCopyRef(CopyTraits,
                                  CopyTraitsSharedCopyRef):
    __test__ = False

    def setUp(self):
        print '\n***TestCopyTraitsSharedCopyRef.setUp ',
        #super(TestCopyTraitsSharedCopyRef,self).setUp()
        self.set_shared_copy('ref')
        return


# The next three tests demonstrate that a 'ref' trait is always copied as a
# reference regardless of the copy argument to copy_traits.  That is, shallow
# and deep are indistinguishable.
class TestCopyTraitsCopyNotSpecifiedSharedRef(CopyTraitsBase,
                                              TestCopyTraitsSharedCopyRef):
    __test__ = True

    def setUp(self):
        print '\n*TestCopyTraitsCopyNotSpecifiedSharedRef.setUp',
        CopyTraitsBase.setUp(self)
        TestCopyTraitsSharedCopyRef.setUp(self)
        self.baz2.copy_traits(self.baz)
        return


class TestCopyTraitsCopyShallowSharedRef(CopyTraitsBase,
                                         TestCopyTraitsSharedCopyRef):
    __test__ = True

    def setUp(self):
        print '\n*TestCopyTraitsCopyShallowSharedRef.setUp',
        CopyTraitsBase.setUp(self)
        TestCopyTraitsSharedCopyRef.setUp(self)
        self.baz2.copy_traits(self.baz, copy='shallow')
        return


class TestCopyTraitsCopyDeepSharedRef(CopyTraitsBase,
                                      TestCopyTraitsSharedCopyRef):
    __test__ = True

    def setUp(self):
        print '\n*TestCopyTraitsCopyDeepSharedRef.setUp',
        CopyTraitsBase.setUp(self)
        TestCopyTraitsSharedCopyRef.setUp(self)
        self.baz2.copy_traits(self.baz, copy='deep')
        return
### EOF