def test_applicative_should_call_memoize_saved_value(lazy_spy):
lazy = Lazy(lazy_spy.fn)
value1 = lazy.get()
assert lazy_spy.fn.call_count == 1
value2 = lazy.get()
assert lazy_spy.fn.call_count == 1
assert value1 is value2
def test_applicative_eq_evaluated():
lazy1 = Lazy(fn)
lazy2 = Lazy(fn)
lazy1.get()
assert lazy1 != lazy2
lazy2.get()
assert lazy1 == lazy2
def test_applicative_eq_value():
lazy1 = Lazy(random)
lazy2 = Lazy(random)
lazy1.get()
lazy2.get()
assert lazy1 == lazy1
assert lazy2 == lazy2
assert lazy1 != lazy2
def test_applicative_should_call_stored_function_during_fold_method_call(
lazy_spy):
applicative = Lazy(lazy_spy.fn)
assert lazy_spy.fn.call_count == 0
assert applicative.get() == 42
assert lazy_spy.fn.call_count == 1
def test_applicative_should_not_call_mapper_until_call_get(lazy_spy):
applicative = Lazy(lazy_spy.fn).map(lazy_spy.mapper)
assert lazy_spy.fn.call_count == 0
assert lazy_spy.mapper.call_count == 0
assert applicative.get() == 43
assert lazy_spy.fn.call_count == 1
assert lazy_spy.mapper.call_count == 1
def test_applicative_should_not_call_binder_until_call_get(lazy_spy):
lazy = Lazy(lazy_spy.fn)
assert lazy_spy.fn.call_count == 0
assert lazy_spy.binder.call_count == 0
lazy = lazy.bind(lazy_spy.binder)
assert lazy_spy.fn.call_count == 0
assert lazy_spy.binder.call_count == 0
result = lazy.get()
assert lazy_spy.fn.call_count == 1
assert lazy_spy.binder.call_count == 1
assert result == 43