sbt-btbt-workshop-003_TweeterPlugin.scala

package sbttweeter

import sbt._
import sbt.Keys._

object TweeterKeys {
  /* Instantiate your setting, task, and input task keys here */
}

object TweeterPlugin extends AutoPlugin {

  object autoImport {
    /* Whatever you want brought into scope automatically for users of your plugin */
    val TweeterKeys = sbttweeter.TweeterKeys
  }

  override def projectSettings = Seq(
    /* Whatever settings/behavior you want to make available to the project that includes your plugin */
  )
}

sbt-btbt-workshop-003_TweeterService.scala

package com.example.sbt

import scala.util.Try

trait TweeterService {
  def post(tweet: String): Try[_]
}

sbt-btbt-workshop-003_TweeterServiceSpec.scala

package com.example.sbt

import scala.util.Failure
import org.scalatest.{FlatSpec, Matchers}

class TweeterServiceSpec extends FlatSpec with Matchers {

  behavior of "TweeterService"

  it should "return a failure when ..." in {
    pending
    val service: TweeterService = ???
    val result = service.post("This tweet should never make it out!")
    result shouldBe a[Failure[_]]
  }
}