Inherited protocol methods issue

inherited.playground

import Foundation

protocol Profile {
    func localName() -> String
}

protocol AccountProfile: Profile {
    var accountName: String { get }
}

class MockAccountProfile: AccountProfile {
    private let name: String = "mockaccount"
    
    init() {
    }
    
    func localName() -> String {
        return name
    }
    
    var accountName: String {
        get {
            return "[email protected]"
        }
    }
}

class TestAccountManager {
    let loginCallback: (account: AccountProfile) -> ()
    init(loginCallback: (account: AccountProfile) -> ()) {
        self.loginCallback = loginCallback
    }

    func login(username: String, password: String) {
        let account = MockAccountProfile()
        self.loginCallback(account: account)
    }
}

// If we do things directly, it works.
let p: Profile = MockAccountProfile()
(p as MockAccountProfile).name
p.localName()

// Inside a callback, dispatch only works if we're explicit about the type.
func loginCallback (profile: Profile) {
    profile is MockAccountProfile
    (profile as MockAccountProfile).name
    (profile as MockAccountProfile).localName()
    profile.localName()
}

TestAccountManager(loginCallback: loginCallback).login("foo", password: "bar")

Running this in a Playground yields EXC_BAD_ACCESS on line 50.

Nothing changes if localName is also declared in AccountProfile around line 8, FWIW.