def test_nested() -> None:
# matcher[r][g][b]: (int, int, int)
matcher = match({
Color.red:
match({
Color.red:
forall(Color, (255, 0, 0)),
Color.green:
match({
Color.red: (255, 255, 0),
Color.green: (255, 255, 0),
Color.blue: (255, 255, 255),
}),
Color.blue:
forall(Color, (255, 0, 0)),
}),
Color.green:
forall(Color, forall(Color, (0, 0, 0))),
Color.blue:
forall(Color, forall(Color, (0, 0, 0))),
})
assert matcher[Color.red][Color.green][Color.blue] == (255, 255, 255)
assert matcher[Color.red][Color.green][Color.red] == (255, 255, 0)
assert matcher[Color.red][Color.green][Color.green] == (255, 255, 0)
assert matcher[Color.red][Color.blue][Color.blue] == (255, 0, 0)
assert matcher[Color.red][Color.red][Color.blue] == (255, 0, 0)
assert matcher[Color.green][Color.green][Color.blue] == (0, 0, 0)
assert matcher[Color.blue][Color.green][Color.blue] == (0, 0, 0)
def test_match_invalid_input() -> None:
with pytest.raises(TypeError, match="expecting a dict"):
match([ # type: ignore
(Color.red, "Red"),
(Color.green, "Green"),
(Color.blue, "Blue"),
])
with pytest.raises(
TypeError,
match="the first key of the given dict must be an enum attribute"):
match({
...: (255, 0, 0),
Color.green: (0, 255, 0),
Color.blue: (0, 0, 255)
})
def test_match_all_possibilities() -> None:
matcher = match({
Color.red: (255, 0, 0),
Color.green: (0, 255, 0),
Color.blue: (0, 0, 255)
})
assert matcher[Color.red] == (255, 0, 0)
assert matcher[Color.green] == (0, 255, 0)
assert matcher[Color.blue] == (0, 0, 255)
def test_match_missing_possibility() -> None:
with pytest.raises(ValueError,
match="missing possibilities: Color.green, Color.blue"):
match({Color.red: "Red"})
def test_match_default() -> None:
matcher = match({Color.red: "Red", ...: "Other than Red"})
assert matcher[Color.red] == "Red"
assert matcher[Color.green] == "Other than Red"
assert matcher[Color.blue] == "Other than Red"