Beispiel #1
0
def test_true_false():
    x = symbols('x')

    assert true is S.true
    assert false is S.false
    assert true is not True
    assert false is not False
    assert true
    assert not false
    assert true == True
    assert false == False
    assert not (true == False)
    assert not (false == True)
    assert not (true == false)

    assert hash(true) == hash(True)
    assert hash(false) == hash(False)
    assert len(set([true, True])) == len(set([false, False])) == 1

    assert isinstance(true, BooleanAtom)
    assert isinstance(false, BooleanAtom)
    # We don't want to subclass from bool, because bool subclasses from
    # int. But operators like &, |, ^, <<, >>, and ~ act differently on 0 and
    # 1 then we want them to on true and false.  See the docstrings of the
    # various And, Or, etc. functions for examples.
    assert not isinstance(true, bool)
    assert not isinstance(false, bool)

    # Note: using 'is' comparison is important here. We want these to return
    # true and false, not True and False

    assert Not(true) is false
    assert Not(True) is false
    assert Not(false) is true
    assert Not(False) is true
    assert ~true is false
    assert ~false is true

    for T, F in cartes([True, true], [False, false]):
        assert And(T, F) is false
        assert And(F, T) is false
        assert And(F, F) is false
        assert And(T, T) is true
        assert And(T, x) == x
        assert And(F, x) is false
        if not (T is True and F is False):
            assert T & F is false
            assert F & T is false
        if not F is False:
            assert F & F is false
        if not T is True:
            assert T & T is true

        assert Or(T, F) is true
        assert Or(F, T) is true
        assert Or(F, F) is false
        assert Or(T, T) is true
        assert Or(T, x) is true
        assert Or(F, x) == x
        if not (T is True and F is False):
            assert T | F is true
            assert F | T is true
        if not F is False:
            assert F | F is false
        if not T is True:
            assert T | T is true

        assert Xor(T, F) is true
        assert Xor(F, T) is true
        assert Xor(F, F) is false
        assert Xor(T, T) is false
        assert Xor(T, x) == ~x
        assert Xor(F, x) == x
        if not (T is True and F is False):
            assert T ^ F is true
            assert F ^ T is true
        if not F is False:
            assert F ^ F is false
        if not T is True:
            assert T ^ T is false

        assert Nand(T, F) is true
        assert Nand(F, T) is true
        assert Nand(F, F) is true
        assert Nand(T, T) is false
        assert Nand(T, x) == ~x
        assert Nand(F, x) is true

        assert Nor(T, F) is false
        assert Nor(F, T) is false
        assert Nor(F, F) is true
        assert Nor(T, T) is false
        assert Nor(T, x) is false
        assert Nor(F, x) == ~x

        assert Implies(T, F) is false
        assert Implies(F, T) is true
        assert Implies(F, F) is true
        assert Implies(T, T) is true
        assert Implies(T, x) == x
        assert Implies(F, x) is true
        assert Implies(x, T) is true
        assert Implies(x, F) == ~x
        if not (T is True and F is False):
            assert T >> F is false
            assert F << T is false
            assert F >> T is true
            assert T << F is true
        if not F is False:
            assert F >> F is true
            assert F << F is true
        if not T is True:
            assert T >> T is true
            assert T << T is true

        assert Equivalent(T, F) is false
        assert Equivalent(F, T) is false
        assert Equivalent(F, F) is true
        assert Equivalent(T, T) is true
        assert Equivalent(T, x) == x
        assert Equivalent(F, x) == ~x
        assert Equivalent(x, T) == x
        assert Equivalent(x, F) == ~x

        assert ITE(T, T, T) is true
        assert ITE(T, T, F) is true
        assert ITE(T, F, T) is false
        assert ITE(T, F, F) is false
        assert ITE(F, T, T) is true
        assert ITE(F, T, F) is false
        assert ITE(F, F, T) is true
        assert ITE(F, F, F) is false
Beispiel #2
0
def test_true_false():
    assert true is S.true
    assert false is S.false
    assert true is not True
    assert false is not False
    assert true
    assert not false
    assert true == True
    assert false == False
    assert not (true == False)
    assert not (false == True)
    assert not (true == false)

    assert hash(true) == hash(True)
    assert hash(false) == hash(False)
    assert len({true, True}) == len({false, False}) == 1

    assert isinstance(true, BooleanAtom)
    assert isinstance(false, BooleanAtom)
    # We don't want to subclass from bool, because bool subclasses from
    # int. But operators like &, |, ^, <<, >>, and ~ act differently on 0 and
    # 1 then we want them to on true and false.  See the docstrings of the
    # various And, Or, etc. functions for examples.
    assert not isinstance(true, bool)
    assert not isinstance(false, bool)

    # Note: using 'is' comparison is important here. We want these to return
    # true and false, not True and False

    assert Not(true) is false
    assert Not(True) is false
    assert Not(false) is true
    assert Not(False) is true
    assert ~true is false
    assert ~false is true

    for T, F in cartes([True, true], [False, false]):
        assert And(T, F) is false
        assert And(F, T) is false
        assert And(F, F) is false
        assert And(T, T) is true
        assert And(T, x) == x
        assert And(F, x) is false
        if not (T is True and F is False):
            assert T & F is false
            assert F & T is false
        if not F is False:
            assert F & F is false
        if not T is True:
            assert T & T is true

        assert Or(T, F) is true
        assert Or(F, T) is true
        assert Or(F, F) is false
        assert Or(T, T) is true
        assert Or(T, x) is true
        assert Or(F, x) == x
        if not (T is True and F is False):
            assert T | F is true
            assert F | T is true
        if not F is False:
            assert F | F is false
        if not T is True:
            assert T | T is true

        assert Xor(T, F) is true
        assert Xor(F, T) is true
        assert Xor(F, F) is false
        assert Xor(T, T) is false
        assert Xor(T, x) == ~x
        assert Xor(F, x) == x
        if not (T is True and F is False):
            assert T ^ F is true
            assert F ^ T is true
        if not F is False:
            assert F ^ F is false
        if not T is True:
            assert T ^ T is false

        assert Nand(T, F) is true
        assert Nand(F, T) is true
        assert Nand(F, F) is true
        assert Nand(T, T) is false
        assert Nand(T, x) == ~x
        assert Nand(F, x) is true

        assert Nor(T, F) is false
        assert Nor(F, T) is false
        assert Nor(F, F) is true
        assert Nor(T, T) is false
        assert Nor(T, x) is false
        assert Nor(F, x) == ~x

        assert Implies(T, F) is false
        assert Implies(F, T) is true
        assert Implies(F, F) is true
        assert Implies(T, T) is true
        assert Implies(T, x) == x
        assert Implies(F, x) is true
        assert Implies(x, T) is true
        assert Implies(x, F) == ~x
        if not (T is True and F is False):
            assert T >> F is false
            assert F << T is false
            assert F >> T is true
            assert T << F is true
        if not F is False:
            assert F >> F is true
            assert F << F is true
        if not T is True:
            assert T >> T is true
            assert T << T is true

        assert Equivalent(T, F) is false
        assert Equivalent(F, T) is false
        assert Equivalent(F, F) is true
        assert Equivalent(T, T) is true
        assert Equivalent(T, x) == x
        assert Equivalent(F, x) == ~x
        assert Equivalent(x, T) == x
        assert Equivalent(x, F) == ~x

        assert ITE(T, T, T) is true
        assert ITE(T, T, F) is true
        assert ITE(T, F, T) is false
        assert ITE(T, F, F) is false
        assert ITE(F, T, T) is true
        assert ITE(F, T, F) is false
        assert ITE(F, F, T) is true
        assert ITE(F, F, F) is false

    assert all(i.simplify(1, 2) is i for i in (S.true, S.false))