Detect and validate duplicate registrations within an Assembly

[bradfol]

We are able to detect duplicates from within a single module at parse/compile time, so it will be good to fail early and provide an error to the developer.

[skorulis-ap]

I think both arguments and ifConfigCondition are needed in this key for uniqueness. ifConfigCondition is a little more complex as per the following code.

# if DEBUG
container.register(Service.self, factory: DebugService.init)
#endif

# if RELEASE
container.register(Service.self, factory: ReleaseService.init)
#endif

container.register(Service.self, factory: DuplicateService.init)

The DEBUG and RELEASE configurations don't clash (but there's no way to know that from code that those are exclusive) but both clash with the registration that isn't wrapped.

[bradfol]

Ah thanks yes i'll update

[bradfol]

Updated to include arguments. Still need to work on the ifConfigCondition check as well

[bradfol]

Also i realized i need to separate the assemblies by TargetResolver because we have shadowed registrations for Entities

[skorulis-ap]

Nit: registrationCount could be removed by checking if the registrationSet contains the key already

Suggested change

	registrationCount += 1
	registrationSet.insert(Key(service: registration.service, name: registration.name))
	guard registrationCount == registrationSet.count else {
	throw ConfigurationSetParsingError.detectedDuplicateRegistration(
	service: registration.service,
	name: registration.name
	)
	}
	let key = Key(service: registration.service, name: registration.name)
	guard !registrationSet.contains(key) else {
	throw ConfigurationSetParsingError.detectedDuplicateRegistration(
	service: registration.service,
	name: registration.name
	)
	}
	registrationSet.insert(key)

[bradfol]

Thanks, updated

[skorulis-ap]

This looks safe but I'm not sure if there are any edge cases in cash-ios that might prevent building.

[bradfol]

Ok i updated to add support for assemblies with multiple different TargetResolvers within the same configuration set. Ran against cash-ios and it has detected some duplicates.