creating_a_seam_final.kt

class TaskChecker(
    seamToAssigner: ((Task) -> Unit)? = null
) {

    private val safeSendTaskToAssigner: (Task) -> Unit = seamToAssigner ?: ::sendTaskToAssigner

    fun check(task: Task): CheckResult {

        if (isNotCreatedInCurrentWeek(task)) return Invalid
        if (isResolved(task)) return Invalid
        if (isNotAssigned(task)) return Invalid

        return Valid
    }

    private fun isNotAssigned(task: Task): Boolean {
        if (task.assignedTo != Nobody) return false

        safeSendTaskToAssigner(task)

        return true
    }

    private fun sendTaskToAssigner(task: Task) {
        val connection = Connection()
        val assigner = TaskAssigner(connection)
        assigner.add(task)
    }

    //...
}