import pytest

from pkgcore.resolver.pigeonholes import PigeonHoledSlots
from pkgcore.restrictions import restriction

from .test_choice_point import fake_package


class fake_blocker(restriction.base):
    __slots__ = ("blocks", "key")

    def __init__(self, key, blocks=()):
        restriction.base.__init__(self)
        if not isinstance(blocks, (list, tuple)):
            blocks = [blocks]
        object.__setattr__(self, "key", key)
        object.__setattr__(self, "blocks", blocks)

    def __str__(self):
        return f"fake_atom({self.key}, {self.blocks})"

    def match(self, obj):
        return any(x is obj for x in self.blocks)


class TestSlot:
    def test_add(self):
        c = PigeonHoledSlots()
        o = fake_package()
        assert not c.fill_slotting(o)
        # test that it doesn't invalidly block o when (innefficiently)
        # doing a re-add
        assert c.fill_slotting(o) == [o]
        assert c.fill_slotting(fake_package()) == [o]
        assert not c.fill_slotting(fake_package(slot=1, key=1))

    def test_add_limiter(self):
        c = PigeonHoledSlots()
        p = fake_package()
        o = fake_blocker(None, p)
        assert not c.fill_slotting(p)
        assert c.add_limiter(o) == [p]
        c.remove_slotting(p)
        assert c.fill_slotting(p) == [o]
        # note we're doing 'is' tests in fake_blocker
        assert not c.fill_slotting(fake_package())

    def test_remove_slotting(self):
        c = PigeonHoledSlots()
        p, p2 = fake_package(), fake_package(slot=2)
        o = fake_blocker(None, p)
        assert not c.add_limiter(o)
        c.remove_limiter(o)
        with pytest.raises(KeyError):
            c.remove_slotting(o)
        with pytest.raises(KeyError):
            c.remove_limiter(o)
        assert not c.fill_slotting(p)
        assert not c.fill_slotting(p2)
        c.remove_slotting(p)
        c.remove_slotting(p2)
