juergen.rocks > Python-Klassen-Initialisierung: Bemerkenswertes Verhalten

nested.py

# -*- coding: utf-8 -*-

# Copyright 2015 Juergen Edelbluth
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

__author__ = 'Juergen Edelbluth'


class A(object):

    class ASub:

        A_SUB_VALUE = 1

    def __init__(self, a=ASub.A_SUB_VALUE):
        self.__a = a

    @property
    def a(self):
        return self.__a


class B(object):

    class BSub:

        B_SUB_VALUE = 1

        @classmethod
        def get_b(cls):
            return cls.B_SUB_VALUE

    def __init__(self, b=BSub.get_b()):
        self.__b = b

    @property
    def b(self):
        return self.__b


class C(object):

    class CSub:

        C_SUB_VALUE = 1

    def __init__(self, c=None):
        self.__c = c
        if c is None:
            self.__c = C.CSub.C_SUB_VALUE

    @property
    def c(self):
        return self.__c


class D(object):

    class DSub:

        D_SUB_VALUE = 1

        @classmethod
        def get_d(cls):
            return cls.D_SUB_VALUE

    def __init__(self, d=None):
        self.__d = d
        if d is None:
            self.__d = D.DSub.get_d()

    @property
    def d(self):
        return self.__d

plain.py

# -*- coding: utf-8 -*-

# Copyright 2015 Juergen Edelbluth
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

__author__ = 'Juergen Edelbluth'


class AValue(object):

    A_VALUE = 1


class A(object):

    def __init__(self, a=AValue.A_VALUE):
        self.__a = a

    @property
    def a(self):
        return self.__a

test.py

# -*- coding: utf-8 -*-

# Copyright 2015 Juergen Edelbluth
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

__author__ = 'Juergen Edelbluth'


from unittest import TestCase
import nested
import plain


class NestedTest(TestCase):

    def test_a(self):

        n1 = nested.A()
        self.assertEqual(n1.a, 1)

        nested.A.ASub.A_SUB_VALUE = 10
        n2 = nested.A()
        self.assertEqual(n2.a, 1)

        n3 = nested.A(100)
        self.assertEqual(n3.a, 100)

    def test_b(self):

        n1 = nested.B()
        self.assertEqual(n1.b, 1)

        nested.B.BSub.B_SUB_VALUE = 10
        n2 = nested.B()
        self.assertEqual(n2.b, 1)

        n3 = nested.B(100)
        self.assertEqual(n3.b, 100)

    def test_c(self):

        n1 = nested.C()
        self.assertEqual(n1.c, 1)

        nested.C.CSub.C_SUB_VALUE = 10
        n2 = nested.C()
        self.assertEqual(n2.c, 10)

        n3 = nested.C(100)
        self.assertEqual(n3.c, 100)

    def test_d(self):

        n1 = nested.D()
        self.assertEqual(n1.d, 1)

        nested.D.DSub.D_SUB_VALUE = 10
        n2 = nested.D()
        self.assertEqual(n2.d, 10)

        n3 = nested.D(100)
        self.assertEqual(n3.d, 100)


class PlainTest(TestCase):

    def test_a(self):

        p1 = plain.A()
        self.assertEqual(p1.a, 1)

        plain.AValue.A_VALUE = 10
        p2 = plain.A()
        self.assertEqual(p2.a, 1)

        p3 = plain.A(100)
        self.assertEqual(p3.a, 100)