def test_rescue_failure():
"""Ensures that rescue works for Failure container."""
def factory(inner_value) -> RCR[int, str, int]:
return RCR.from_failure(inner_value * 2)
assert RCR.from_value(5).rescue(factory, )(0) == RCR.from_value(5)(0)
assert RCR.from_failure(5).rescue(factory, )(0) == RCR.from_failure(10)(0)
def test_lash_success():
"""Ensures that lash works for Success container."""
def factory(inner_value) -> RCR[int, str, int]:
return RCR.from_value(inner_value * 2)
assert RCR.from_value(5).lash(factory, )(0) == RCR.from_value(5)(0)
assert RCR.from_failure(5).lash(factory, )(0) == RCR.from_value(10)(0)
def test_rescue_with_context_result():
"""Ensures that functions can be composed and return type is correct."""
rescued = rescue(_context_result_function)
assert rescued(RequiresContextResult.from_value(1), )(1) == Success(1)
assert rescued(RequiresContextResult.from_failure(1), )(1) == Success(2)
assert rescued(
RequiresContextResult.from_failure(0), )(1) == Failure('nope')
def test_bind_regular_context():
"""Ensures that regular ``RequiresContext`` can be bound."""
def factory(inner_value: int) -> RequiresContext[float, int]:
return RequiresContext(lambda deps: inner_value / deps)
first: RCR[int, str, int] = RCR.from_value(1)
third: RCR[int, str, int] = RCR.from_failure('a')
assert first.bind_context(factory)(2) == Success(0.5)
assert RCR.from_value(2).bind_context(factory, )(1) == Success(2.0)
assert third.bind_context(factory)(1) == Failure('a')
def test_rescue_success():
"""Ensures that rescue works for Success container."""
def factory(inner_value) -> RCR[int, int, str]:
return RCR.from_success(inner_value * 2)
assert RCR.from_success(5).rescue(
factory,
)(0) == RCR.from_success(5)(0)
assert RCR.from_failure(5).rescue(
factory,
)(0) == RCR.from_success(10)(0)
def test_bind_regular_result():
"""Ensures that regular ``Result`` can be bound."""
def factory(inner_value: int) -> Result[int, str]:
if inner_value > 0:
return Success(inner_value + 1)
return Failure('nope')
first: RCR[int, str, int] = RCR.from_value(1)
third: RCR[int, str, int] = RCR.from_failure('a')
assert first.bind_result(factory)(RCR.empty) == Success(2)
assert RCR.from_value(0).bind_result(factory, )(
RCR.empty) == Failure('nope')
assert third.bind_result(factory)(RCR.empty) == Failure('a')
def test_bind():
"""Ensures that bind works."""
def factory(inner_value: int) -> RCR[float, str, int]:
if inner_value > 0:
return RCR(lambda deps: Success(inner_value / deps))
return RCR.from_failure(str(inner_value))
input_value = 5
bound: RCR[int, str, int] = RCR.from_value(input_value)
assert bound.bind(factory)(2) == factory(input_value)(2)
assert bound.bind(factory)(2) == Success(2.5)
assert RCR.from_value(0).bind(
factory, )(2) == factory(0)(2) == Failure('0')
def test_requires_context_aliases():
"""Ensures that ReaderResult correctly typecast."""
container: ReaderResultE[float, int] = _function(1)
container2: ReaderResult[float, Exception, int] = _function(1)
container3: ReaderResultE[float, int] = ReaderResultE.from_value(10.0, )
container4: ReaderResultE[float, int] = ReaderResult.from_value(10.0)
assert container(0) == container2(0) == container3(0) == container4(0)
assert container(0) == RequiresContextResult.from_value(10.0)(0)
def test_requires_context_resulte():
"""Ensures that RequiresContextResultE correctly typecast."""
container: RequiresContextResult[float, Exception, int] = _function(1)
assert container(0) == RequiresContextResult.from_value(10.0)(0)
def test_requires_context_result_immutable():
"""Ensures that container is immutable."""
with pytest.raises(ImmutableStateError):
RequiresContextResult.from_success(1).abc = 1
from returns.context import ContextResult, RequiresContextResult
from returns.primitives.exceptions import ImmutableStateError
from returns.primitives.interfaces import (
Altable,
Bindable,
Fixable,
Mappable,
Rescueable,
Unitable,
Unwrapable,
)
from returns.result import Failure, Success
@pytest.mark.parametrize('container', [
RequiresContextResult(lambda _: Success(1)),
RequiresContextResult(lambda _: Failure(1)),
RequiresContextResult.from_success(1),
RequiresContextResult.from_failure(1),
RequiresContextResult.from_result(Success(1)),
RequiresContextResult.from_result(Failure(1)),
ContextResult.ask(),
])
@pytest.mark.parametrize('protocol', [
Bindable,
Mappable,
Rescueable,
Unwrapable,
Altable,
Fixable,
Unitable,
# Nope:
(Nothing, Nothing),
(Failure(Failure('a')), Failure(Failure('a'))),
(Failure(Success('a')), Failure(Success('a'))),
(IOFailure(IOFailure('a')), IOFailure(IOFailure('a'))),
(IOFailure(IOSuccess('a')), IOFailure(IOSuccess('a'))),
])
def test_flatten(container, merged):
"""Ensures that `flatten` is always returning the correct type."""
assert flatten(container) == merged
@pytest.mark.parametrize(('container', 'merged'), [
(
RequiresContextResult.from_value(
RequiresContextResult.from_value(1), ),
RequiresContextResult.from_value(1),
),
(
RequiresContextIOResult.from_value(
RequiresContextIOResult.from_value(1), ),
RequiresContextIOResult.from_value(1),
),
(
RequiresContext.from_value(RequiresContext.from_value(1)),
RequiresContext.from_value(1),
),
])
def test_flatten_context(container, merged):
"""Ensures that `flatten` is always returning the correct type."""
assert flatten(container)(...) == merged(...)
def test_apply_with_context_result():
"""Ensures that functions can be composed and return type is correct."""
applied = apply(RequiresContextResult.from_value(_function))
assert applied(RequiresContextResult.from_value(1), )(...) == Success('2')
def test_bind_with_context_result():
"""Ensures that functions can be composed and return type is correct."""
binded = bind(_context_result_function)
assert binded(RequiresContextResult.from_success(3))(5) == Success(8)
def factory(inner_value: int) -> RequiresContextResult[float, str, int]:
return RequiresContextResult(lambda deps: Success(inner_value / deps))
def _context_result_function(
argument: int, ) -> RequiresContextResult[int, int, str]:
if argument > 0:
return RequiresContextResult(lambda deps: Success(argument + deps))
return RequiresContextResult.from_failure('nope')
def _function(arg: int) -> RequiresContextResultE[float, int]:
if arg == 0:
return RequiresContextResult.from_failure(
ZeroDivisionError('Divided by 0'), )
return RequiresContextResult.from_value(10 / arg)
def test_immutable_copy():
"""Ensures that helper returns it self when passed to copy function."""
context_result = RequiresContextResult.from_value(1)
assert context_result is copy(context_result)
def factory(inner_value) -> RCR[int, str, int]:
return RCR.from_value(inner_value * 2)
def test_return_false_with_requires_context_result_container(): # noqa: WPS118
"""Ensures `is_io` function will return False for RequiresContextResult."""
assert is_io(RequiresContextResult.from_success(Success(True))) is False
def factory(inner_value) -> RCR[int, int, str]:
return RCR.from_success(inner_value * 2)
def factory(inner_value) -> RCR[int, int, str]:
return RCR.from_failure(inner_value * 2)
def factory(inner_value: int) -> RCR[int, float, str]:
if inner_value > 0:
return RCR(lambda deps: Success(inner_value / deps))
return RCR.from_failure(str(inner_value))
def _context_result_function(
argument: int, ) -> RequiresContextResult[int, int, str]:
return RequiresContextResult(lambda other: Success(argument + other))
):
if should_lash:
return container.lash(lambda inner: container.from_failure(inner))
return container.bind(lambda inner: container.from_value(inner))
@pytest.mark.parametrize('container', [
Success(1),
Failure(1),
IOSuccess(1),
IOFailure(1),
RequiresContextIOResult.from_value(1),
RequiresContextIOResult.from_failure(1),
RequiresContextFutureResult.from_value(1),
RequiresContextFutureResult.from_failure(1),
RequiresContextResult.from_value(1),
RequiresContextResult.from_failure(1),
FutureResult.from_value(1),
FutureResult.from_failure(1),
])
@pytest.mark.parametrize('kwargs', [
{
'should_lash': True
},
])
def test_error_handled(container, returns, kwargs):
"""Demo on how to use ``pytest`` helpers to work with error handling."""
error_handled = _under_test(container, **kwargs)
assert returns.is_error_handled(error_handled)
assert returns.is_error_handled(error_handled.map(identity))
(IOSuccess(IOSuccess(1)), IOSuccess(1)),
(Some(Some(None)), Nothing),
(Some(Some([])), Some([])),
# Nope:
(Failure(Failure('a')), Failure(Failure('a'))),
(IOFailure(IOFailure('a')), IOFailure(IOFailure('a'))),
])
def test_flatten(container, merged):
"""Ensures that `flatten` is always returning the correct type."""
assert flatten(container) == merged
@pytest.mark.parametrize(('container', 'merged'), [
(
RequiresContextResult.from_success(
RequiresContextResult.from_success(1), ),
RequiresContextResult.from_success(1),
),
(
RequiresContextIOResult.from_success(
RequiresContextIOResult.from_success(1), ),
RequiresContextIOResult.from_success(1),
),
(
RequiresContext.from_value(RequiresContext.from_value(1)),
RequiresContext.from_value(1),
),
])
def test_flatten_context(container, merged):
"""Ensures that `flatten` is always returning the correct type."""
assert flatten(container)(...) == merged(...)
):
if should_rescue:
return container.rescue(lambda inner: container.from_failure(inner))
if should_fix:
return container.fix(identity)
return container.bind(lambda inner: container.from_success(inner))
@pytest.mark.parametrize('container', [
Success(1),
Failure(1),
IOSuccess(1),
IOFailure(1),
RequiresContextIOResult.from_success(1),
RequiresContextIOResult.from_failure(1),
RequiresContextResult.from_success(1),
RequiresContextResult.from_failure(1),
])
@pytest.mark.parametrize('kwargs', [
{'should_rescue': True},
{'should_fix': True},
{'should_rescue': True, 'should_fix': True},
])
def test_error_handled(container, returns, kwargs):
"""Demo on how to use ``pytest`` helpers to work with error handling."""
error_handled = _under_test(container, **kwargs)
assert returns.is_error_handled(error_handled)
assert returns.is_error_handled(error_handled.map(identity))
assert returns.is_error_handled(error_handled.alt(identity))
