Non-Proxy Custom Scopes

[RyanHoldren]

Issue description

I suspect this is not a bug, but rather that I am just misunderstanding how Micronaut works.

Consider this example:

@Documented
@Retention(RUNTIME)
@Scope
@Target({TYPE, METHOD})
public @interface SpecialBean {}

@Singleton
public class SpeciaBeanScope implements CustomScope<SpecialBean> {

	private final Map<BeanIdentifier, CreatedBean<?>> beans = new ConcurrentHashMap<>();

	@Override
	public Class<SpecialBean> annotationType() {
		return SpecialBean.class;
	}

	@Override
	public <T> T getOrCreate(BeanCreationContext<T> context) {
		final var id = context.id();
		return (T) beans.computeIfAbsent(id, key -> context.create()).bean();
	}

	// ...

}

@SpecialBean
public class SpecialService {

}

I expected that SpeciaBeanScope.getOrCreate() would be called for SpecialService but it isn't. It looks like the scope is never looked up by DefaultBeanContext.getScopedBeanForDefinition() because SpecialBean is not annotated with @ScopedProxy.

Here is the relevant code from DefaultBeanContext.getScopedBeanForDefinition():

if (registeredScope == null && !isProxy && isScopedProxyDefinition) {
	registeredScope = customScopeRegistry.findDeclaredScope(definition).orElse(null);
}

This seems very intentional, but I am not sure why. Why do custom scopes have to be proxies? In my case, I cannot simply add @ScopeProxy because some of my beans are final.

[Paullo612]

Looks like correct condition would be

if (registeredScope == null && ((isScopedProxyDefinition && !isProxy) || !isScopedProxyDefinition))

which can be simplified to

if (registeredScope == null && (!isScopedProxyDefinition || !isProxy)).

Also, proxy target bean definition should be searched here only if it is scoped proxy (to make AOP work correctly for non scoped proxies).

Patched locally for now, but looking forward to see this fixed upstream!

It also would be cool to have some API in BeanCreationContext, which could allow to decide whether I should throw NoSuchBeanException from CustomScope#getOrCreate, or just return null (later is relevant when bean is searched through BeanLocator#findBean).