Generic parameter 'Result' could not be inferred

[kgrigsby59]

I have the following:

public struct SpotlightClient {
    public var refreshSpotlightIndex: () async throws -> Void

    public init(refreshSpotlightIndex: @escaping () async throws -> Void) {
        self.refreshSpotlightIndex = refreshSpotlightIndex
    }
}

#if DEBUG
import XCTestDynamicOverlay

extension SpotlightClient {
    public static let unimplemented = Self(
        refreshSpotlightIndex: { XCTUnimplemented("\(Self.self).refreshSpotlightIndex") }
    )
}
#endif

I'm getting a compile error Generic parameter 'Result' could not be inferred on the line with XCTUnimplemented.
Am I doing something wrong or is this not implemented for a function that returns Void?

[stephencelis]

@kgrigsby59 XCTUnimplemented is meant as a dependency "generator" of sorts, so it's responsible for emitting a function that will fail when called later (as opposed to XCTFail, which fails immediately when called). I think you can do the following to get things building:

 extension SpotlightClient {
     public static let unimplemented = Self(
-        refreshSpotlightIndex: { XCTUnimplemented("\(Self.self).refreshSpotlightIndex") }
+        refreshSpotlightIndex: XCTUnimplemented("\(Self.self).refreshSpotlightIndex")
     )
 }

Basically, call XCTUnimplemented in place of the endpoint's closure, not within the endpoint's closure.

[kgrigsby59]

🤦‍♂️