Scala Process - Capture Standard Out and Exit Code

Question

I\'m working with the Scala scala.sys.process library.

I know that I can capture the exit code with ! and the output with !!

Answer 1

You can use ProcessIO. I needed something like that in a Specs2 Test, where I had to check the exit value as well as the output of a process depending on the input on stdin (in and out are of type String):

"the operation" should {
  f"return '$out' on input '$in'" in {
    var res = ""
    val io = new ProcessIO(
      stdin  => { stdin.write(in.getBytes)
                  stdin.close() }, 
      stdout => { res = convertStreamToString(stdout)
                  stdout.close() },
      stderr => { stderr.close() })
    val proc = f"$operation $file".run(io)
    proc.exitValue() must be_==(0)
    res must be_==(out)
  }
}

I figured that might help you. In the example I am ignoring what ever comes from stderr.