With Tuist's µFeature Architecture?

[kimxwan0319]

How can I use swift-dependencies with MFA

Is there anyone who can share my concerns?

• Due to the characteristics of MFA, interfaces that require external access should be placed in the Interface module, implementations in the Source module, and mock objects needed for testing in the Testing module.
  • Structs defining closures -> Interface module
  • Extensions inheriting DependencyKey and implementing liveValue -> Source module
  • Extensions inheriting TestDependencyKey and implementing testValue -> Testing module
• To actually use a Dependency, it must be registered in the DependencyValues extension. So, who should be responsible for this registration?
  • Interface module? ❌
    • Although it seems best since it only needs to be registered once and is accessible by other services depending on the same service, it's not possible because the Interface module does not implement either DependencyKey or TestDependencyKey.
    • There's no way to explicitly implement this... live or test Value is a mandatory element.
  • Source module?
    • If it wasn't added in the interface, it must be necessarily included in the source module to use the registered dependency.
    • If registered publicly in the source module, tests and example modules depending on both source and testing modules can access all liveData and testData of the registered dependency.

    • But how can other services that do not directly depend on the source of a particular service use its dependencies?

[arslaman]

One way to solve this is to store extensions inheriting TestDependencyKey and implementing testValue in the interface module.

[shp7724]

I came across the same question, and I ended up implementing the liveValue in the main app target (which can import all feature modules) and extend DependencyValues with only testValue in the interface module as @arslaman mentioned.

https://swiftpackageindex.com/pointfreeco/swift-dependencies/1.3.0/documentation/dependencies/livepreviewtest#Separating-interface-and-implementation