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

"""Extended if-expressions."""

from ...syntax import macros, test # noqa: F401

from ...test.fixtures import session, testset

from ...syntax import macros, aif, it, cond, local # noqa: F401, F811

def runtests():

with testset("aif (anaphoric if, you're `it`!)"):

# Anaphoric if: aif[test, then, otherwise]

# Magic identifier "it" refers to the test result.

test[aif[2 * 21,

f"it is {it}",

"it is False"] == "it is 42"]

with testset("cond (lispy multi-branch conditional expression)"):

answer = lambda x: cond[x == 2, "two",

x == 3, "three",

"something else"]

test[answer(2) == "two"]

test[answer(3) == "three"]

test[answer(42) == "something else"]

# implicit do: in any part of aif or cond, use extra brackets for a do[] environment

with testset("integration with implicit do"):

print("Testing aif/cond with implicit do")

test[aif[[local[x << 2 * 21], 2 * x], # noqa: F821, the `local[]` macro defines the name on the LHS of the `<<`.

[print("hi"), f"it is {it}"],

[print("ho"), "it is False"]] == "it is 84"]

# each "test" and "then" branch with multiple expressions should have its own

# extra brackets. (Similarly for the final "otherwise" branch.)

answer = lambda x: cond[[local[y << 2 * x], y == 4], [print("hi again"), "two"], # noqa: F821

x == 3, "three",

"something else"]

test[answer(2) == "two"]

test[answer(3) == "three"]

test[answer(4) == "something else"]

if __name__ == '__main__': # pragma: no cover

with session(__file__):

runtests()