sbt 条件 if else 样式配置

Question

我希望能够使用命令行在并行和串行执行 scala 测试之间切换。

带有“test.par”系统属性的工作示例：

val parallelTestOpt = Option(System.getProperty("test.par"))

testOptions in IntegrationTest += Tests.Argument(
  //Configure distributor's pool size
  parallelTestOpt.map(count =>s"-P$count").getOrElse("-P1")
)

lazy val root = (project in file("."))
  .configs(IntegrationTest)
  .settings(Defaults.itSettings,
      //If suites are executed in parallel
      IntegrationTest / parallelExecution := parallelTestOpt.exists(_ != "1"),
      IntegrationTest / testForkedParallel := parallelTestOpt.exists(_ != "1")
  )

“有问题的”部分是parallelTestOpt.map(count =>s"-P$count").getOrElse("-P1")。当未指定“test.par”属性时，我不想提供默认值“-P1”。实现这一目标的最佳做法是什么？

也许整个概念是错误的，我应该以不同的方式来做？

Answer 1

作为一种替代方法，考虑将并行性问题分离到single-argument custom command

commands += Command.single("testpar") { (state, numOfThreads) =>
  s"""set IntegrationTest / testOptions  += Tests.Argument("-P$numOfThreads")"""::
     "set IntegrationTest / parallelExecution := true" ::
     "set IntegrationTest / testForkedParallel := true" ::
     "IntegrationTest / test" :: state
}

并使用testpar 6 执行以使用 6 个线程池运行。

---

解决注释，为了编译时安全尝试

commands += Command.single("testpar") { (state, numOfThreads) =>
  val extracted = Project.extract(state)
  val stateWithParallel= extracted.appendWithSession(
    Seq(
      IntegrationTest / testOptions  += Tests.Argument(s"-P$numOfThreads"),
      IntegrationTest / parallelExecution := true,
      IntegrationTest / testForkedParallel := true,
    ),
    state
  )
  extracted.runTask(IntegrationTest / test, stateWithParallel)
  state
}