vdichev

Exercises
=========

Scala intro
-----------

1. Check if a string has balanced parentheses.

2. There is an inventory of items in a shop costing 615, 452, 356, 184, 172, 156, 135, 115, 78, 56, 48 lv. Find at least one way to spend exactly 992 lv. How about exactly 796 lv.?

vdichev

// Let's say I have 2 or more partial functions with different argument types
// I'm not interested in the result or the result types here
trait Test[A] { val pf: PartialFunction[A,_] }
object TestInt extends Test[Int] { val pf: PartialFunction[Int,String] = { case i => i.toString } }
object TestString extends Test[String] { val pf: PartialFunction[String,Int] = { case s => s.toInt } }

// I want to be able to chain these with orElse:
val pf = TestInt.pf orElse TestString.pf

// ...except that this doesn't work: neither pf.isDefinedAt(1) nor pf.isDefinedAt("str") work

vdichev

email := userList?.findUser("bob")?.email

vdichev

post("/statuses/update.xml", "status" -> "test_msg1")
  \\(<text>test_msg1</text>)
  \\(<screen_name>vdichev</screen_name>)
get("/statuses/public_timeline.xml") \\(<text>test_msg1</text>)
get("/statuses/user_timeline.xml") \\(<text>test_msg1</text>)
get("/statuses/home_timeline.xml") \\(<text>test_msg1</text>)

vdichev

for {
  message <- post("/statuses/update.xml", "status" -> "test_msg1")
    !@ "Couldn't post message" if message.xml must notBeEmpty
  xml <- message.xml
} {
  xml must \\(<text>test_msg1</text>)
}

vdichev

  trait XmlResponse {
    self: TestResponse =>
    def xmlMatch(f: Elem => Unit)
                (implicit errorFunc: ReportFailure): TestResponse = {
      if (this.asInstanceOf[SelfType].code != 200)
        errorFunc.fail("Response status is not 200!")
      xml match {
        case Full(xml) => f(xml); this
        case _ => errorFunc.fail("Response contains no XML!")
      }

vdichev

  override def theHttpClient = {
    val theClient = buildBasicAuthClient(userName, password)
    theClient.getParams.setAuthenticationPreemptive(true)
    theClient
  }

vdichev

get("/account/verify_credentials.xml")
  ! (401, "Login should fail with Unauthorized status")

vdichev

for {
  login <- get("/account/verify_credentials.xml", httpClient, Nil)
    !@ "Failed to log in"
  message <- login.post("/statuses/update.xml", "status" -> "test_msg1")
    !@ "Couldn't post message"
  xml <- message.xml
} {
  // Specs' xml matcher
  xml must \\(<text>test_msg1</text>)
}

vdichev

  implicit val reportError = new ReportFailure {
    def fail(msg: String): Nothing = TwitterAPISpecs.this.fail(msg)
  }