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for finding and fixing issues
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import pytest
from lagom import Singleton, Container
class MyBasicDep:
pass
class MyMoreComplicatedDep:
def __init__(self, some_number):
self.sum_number = some_number
class MyCompositeDep:
def __init__(self, a: MyBasicDep, b: MyMoreComplicatedDep):
self.a = a
self.b = b
@pytest.fixture
def container_with_deps(container: Container):
container.define(MyBasicDep, Singleton(MyBasicDep))
container.define(MyMoreComplicatedDep, Singleton(lambda: MyMoreComplicatedDep(5)))
container.define(MyCompositeDep, Singleton(MyCompositeDep))
return container
def test_singleton_is_only_resolved_once(container_with_deps: Container):
first = container_with_deps.resolve(MyBasicDep)
second = container_with_deps.resolve(MyBasicDep)
assert first is not None
assert first is second
def test_singleton_can_have_construction_logic(container_with_deps: Container):
first = container_with_deps.resolve(MyMoreComplicatedDep)
second = container_with_deps.resolve(MyMoreComplicatedDep)
assert first.sum_number == 5
def test_singleton_can_compose_other_dependencies(container_with_deps: Container):
first = container_with_deps.resolve(MyCompositeDep)
second = container_with_deps.resolve(MyCompositeDep)
assert type(first.a) == MyBasicDep
assert type(first.b) == MyMoreComplicatedDep
meadsteve /
lagom
