Matching on wrong case

[kgrigsby59]

I have two similarly named cases activity and activityTracking. When I ask for the path of activity it gives me activityTracking. Is there something I need to add to do exact matching?

        enum AppRoute: Equatable {
            case activities(ActivitiesRoute?)
        }

        enum ActivitiesRoute: Equatable {
            case activity
            case activityTracking
        }

        let activitiesRouter = OneOf {
            Route(.case(ActivitiesRoute?.none))

            Route(.case(ActivitiesRoute.activity)) {
                Path { "activity"}
            }
            Route(.case(ActivitiesRoute.activityTracking)) {
                Path { "activityTracking" }
            }
        }

        let appRouter = OneOf {

            Route(.case(AppRoute.activities)) {
                Path { "activities" }
                activitiesRouter
            }
        }

        let url = appRouter.path(for: .activities(.activity))
        print(url) // prints   /activities/activityTracking

[mbrandonw]

Parser-printers need to be ordered by most specific to least specific. This is a necessary concept to understand to wield parser-printers correctly, and we talk about it in this episode.

The word "activity" is less specific than "activityTracking" because it is a subset of the latter. So, you need to flip your parser order:

Route(.case(ActivitiesRoute.activityTracking)) {
  Path { "activityTracking" }
}
Route(.case(ActivitiesRoute.activity)) {
  Path { "activity"}
}

We have documentation on this here.

[kgrigsby59]

I tried changing the activitiesRoute to

        let activitiesRouter = OneOf {
            Route(.case(ActivitiesRoute?.none))

            Route(.case(ActivitiesRoute.activityTracking)) {
                Path { "activityTracking" }
            }
            
            Route(.case(ActivitiesRoute.activity)) {
                Path { "activity"}
            }

Asking for .activity works now, but .activityTracking doesn't.

        var url = appRouter.path(for: .activities(.activityTracking))
        print(url) // "/activities/activity"

        url = appRouter.path(for: .activities(.activity))
        print(url) // "/activities/activity"

[mbrandonw]

There is something strange happening with optional promotion in your situation. I don't have time to look into it more, but if you drop the optional it works:

func testFoo() {
  XCTAssertEqual(
    activitiesRouter.path(for: .activityTracking),
    "/activityTracking"
  )
  XCTAssertEqual(
    activitiesRouter.path(for: .activity),
    "/activity"
  )
}

enum AppRoute: Equatable {
  case activities(ActivitiesRoute)
}

enum ActivitiesRoute: Equatable {
  case activity
  case activityTracking
  case none
}

let activitiesRouter = OneOf {
  Route(.case(ActivitiesRoute.none))
  Route(.case(ActivitiesRoute.activityTracking)) {
    Path { "activityTracking" }
  }
  Route(.case(ActivitiesRoute.activity)) {
    Path { "activity"}
  }
}

let appRouter = OneOf {
  Route(.case(AppRoute.activities)) {
    Path { "activities" }
    activitiesRouter
  }
}

[kgrigsby59]

This appear to work.

        let activitiesRouter = Optionally {
            OneOf {
                Route(.case(ActivitiesRoute.activity)) {
                    Path { "activity" }
                }

                Route(.case(ActivitiesRoute.activityTracking)) {
                    Path { "activityTracking"}
                }
            }
        }