Sendable conformance for `Container`

[Eric Horacek]

With Swift 5.10 released and Swift 6 on the horizon, consumers of Factory would expect Container to conform to Sendable as it is intended to be thread safe. However, since it contains a property of containerManager, it's not possible to mark it as such:

Furthermore, when you attempt to conform ContainerManger to sendable, you notice that it has publicly writable properties that are not protected, namely defaultScope but also some other debug ones, so it cannot conform to Sendable either:

To satisfy the Sendable contract, ideally Container and ContainerManager would both have Sendable conformances, though this might require an API rethink.

[Michael Long]

Most of Factory is locked and already thread-safe, so adding complete sendable conformance shouldn't be that difficult.

[Stijn Willems]

The FactoryContext is not thread-safe. It accesses and mutates a struct

extension FactoryContext {
    /// Add argument to global context.
    public static func setArg(_ arg: String, forKey key: String) {
        FactoryContext.current.runtimeArguments[key] = arg
    }
    /// Add argument to global context.
    public static func removeArg(forKey key: String) {
        FactoryContext.current.runtimeArguments.removeValue(forKey: key)
    }
}

This leaves me to think that a lot needs to change in order to go for Swift 6 and sendable checks. Do you think it is feasible to refactor factory to conform to all that?

[Mohamed Emad Hegab]

is there any intension to fix this?

[NachoSoto]

I just sent #209 so at least Factory doesn't fail to compile with Swift 6.

[Michael Long]

See the Swift6 branch. That's Sendable and compatible with Swift concurrency.