package scala.lang.primitives

import org.junit.Assert._
import org.junit.Test
import org.junit.runner.RunWith
import org.junit.runners.JUnit4

import scala.tools.testing.RunTesting

object BoxUnboxTest {
  class VCI(val x: Int) extends AnyVal { override def toString = "" + x }
}

@RunWith(classOf[JUnit4])
class BoxUnboxTest extends RunTesting {
  import runner._

  @Test
  def boxUnboxInt(): Unit = {
    // Once we use 2.12.0-M5 as starr, this code can be run directly in the JUnit test.
    // Some fixes not yet available in M4 make the test fail when compiled with M4.
    val code =
      """import scala.tools.testing.AssertUtil._
        |import org.junit.Assert._
        |
        |def genericNull[T] = null.asInstanceOf[T] // allowed, see SI-4437, point 2
        |
        |val b = new Integer(1)
        |val u = 1
        |
        |assertEquals(1.toInt, u)
        |
        |assertEquals(Predef.int2Integer(1), b)
        |assertEquals(1: Integer, b)
        |assertEquals(Int.box(1), b)
        |assertEquals(1.asInstanceOf[Object], b)
        |
        |assertThrows[ClassCastException]("".asInstanceOf[Integer])
        |
        |assertEquals(Predef.Integer2int(b), u)
        |assertEquals(b: Int, u)
        |assertEquals(Int.unbox(b), u)
        |assertEquals(b.asInstanceOf[Int], u)
        |assertEquals(b.intValue, u)
        |assertEquals(b.toInt, u)
        |intWrapper(b).toInt
        |
        |assertThrows[ClassCastException](Int.unbox(""))
        |assertThrows[ClassCastException]("".asInstanceOf[Int])
        |
        |// null unboxing in various positions
        |
        |val n1 = Int.unbox(null)
        |assertEquals(n1, 0)
        |val n2 = Predef.Integer2int(null)
        |assertEquals(n2, 0)
        |val n3 = (null: Integer): Int
        |assertEquals(n3, 0)
        |val n4 = null.asInstanceOf[Int]
        |assertEquals(n4, 0)
        |val n5 = null.asInstanceOf[Int] == 0
        |assertTrue(n5)
        |val n6 = null.asInstanceOf[Int] == null
        |assertFalse(n6)
        |val n7 = null.asInstanceOf[Int] != 0
        |assertFalse(n7)
        |val n8 = null.asInstanceOf[Int] != null
        |assertTrue(n8)
        |
        |val mp = new java.util.HashMap[Int, Int]
        |val n9 = mp.get(0)
        |assertEquals(n9, 0)
        |val n10 = mp.get(0) == null                    // SI-602
        |assertThrows[AssertionError](assertFalse(n10)) // should not throw
        |
        |def f(a: Any) = "" + a
        |val n11 = f(null.asInstanceOf[Int])
        |assertEquals(n11, "0")
        |
        |def n12 = genericNull[Int]
        |assertEquals(n12, 0)
      """.stripMargin

    run[Unit](code)
  }

  @Test
  def numericConversions(): Unit = {
    // Once we use 2.12.0-M5 as starr, this code can be run directly in the JUnit test.
    val code =
      """import scala.tools.testing.AssertUtil._
        |import org.junit.Assert._
        |
        |val i1 = 1L.asInstanceOf[Int]
        |assertEquals(i1, 1)
        |assertThrows[ClassCastException] {
        |  val i2 = (1L: Any).asInstanceOf[Int] // SI-1448, should not throw. see also SI-4437 point 1.
        |  assertEquals(i2, 1)
        |}
      """.stripMargin
    run[Unit](code)
  }

  @Test
  def boxUnboxBoolean(): Unit = {
    // Once we use 2.12.0-M5 as starr, this code can be run directly in the JUnit test.
    val code =
      """val n1 = Option(null.asInstanceOf[Boolean])
        |n1
      """.stripMargin
    assertEquals(run[Option[Boolean]](code), Some(false))
  }

  @Test
  def boxUnboxUnit(): Unit = {
    // should not use assertEquals in this test: it takes two Object parameters. normally, Unit does
    // not conform to Object, but for Java-defined methods scalac makes an exception and treats them
    // as Any. passing a Unit as Any makes the compiler go through another layer of boxing, so it
    // can hide some bugs (where we actually have a null, but the compiler makes it a ()).

    // Once we use 2.12.0-M5 as starr, this code can be run directly in the JUnit test.
    val code =
      """import scala.tools.testing.AssertUtil._
        |import org.junit.Assert._
        |
        |var v = 0
        |def eff() = { v = 1 }
        |def chk() = { assert(v == 1); v = 0 }
        |
        |val b = runtime.BoxedUnit.UNIT
        |
        |assert(eff() == b); chk()
        |assert(Unit.box(eff()) == b); chk()
        |assert(().asInstanceOf[Object] == b)
        |
        |Unit.unbox({eff(); b}); chk()
        |Unit.unbox({eff(); null}); chk()
        |assertThrows[ClassCastException](Unit.unbox({eff(); ""})); chk()
        |
        |val n1 = null.asInstanceOf[Unit]
        |assert(n1 == b)
        |
        |val n2 = null.asInstanceOf[Unit] == b
        |assert(n2)
        |
        |def f(a: Any) = "" + a
        |val n3 = f(null.asInstanceOf[Unit])
        |assertEquals(n3, "()")
      """.stripMargin
    run[Unit](code)
  }

  @Test
  def t9671(): Unit = {
    // Once we use 2.12.0-M5 as starr, this code can be run directly in the JUnit test.
    val code =
      """import scala.lang.primitives.BoxUnboxTest.VCI
        |
        |def f1(a: Any) = "" + a
        |def f2(a: AnyVal) = "" + a
        |def f3[T](a: T) = "" + a
        |def f4(a: Int) = "" + a
        |def f5(a: VCI) = "" + a
        |def f6(u: Unit) = "" + u
        |
        |def n1: AnyRef = null
        |def n2: Null = null
        |def n3: Any = null
        |def n4[T]: T = null.asInstanceOf[T]
        |
        |def npe(s: => String) = try { s; throw new Error() } catch { case _: NullPointerException => "npe" }
        |
        |    f1(null.asInstanceOf[Int])  +
        |    f1(  n1.asInstanceOf[Int])  +
        |    f1(  n2.asInstanceOf[Int])  +
        |    f1(  n3.asInstanceOf[Int])  +
        |    f1(               n4[Int])  + // "null"
        |"-"                             +
        |    f1(null.asInstanceOf[VCI])  +
        |npe(f1(  n1.asInstanceOf[VCI])) + // SI-8097
        |    f1(  n2.asInstanceOf[VCI])  +
        |npe(f1(  n3.asInstanceOf[VCI])) + // SI-8097
        |    f1(               n4[VCI])  + // "null"
        |"-"                             +
        |    f1(null.asInstanceOf[Unit]) +
        |    f1(  n1.asInstanceOf[Unit]) +
        |    f1(  n2.asInstanceOf[Unit]) +
        |    f1(  n3.asInstanceOf[Unit]) +
        |    f1(               n4[Unit]) + // "null"
        |"-"                             +
        |    f2(null.asInstanceOf[Int])  +
        |    f2(  n1.asInstanceOf[Int])  +
        |    f2(  n2.asInstanceOf[Int])  +
        |    f2(  n3.asInstanceOf[Int])  +
        |    f2(               n4[Int])  + // "null"
        |"-"                             +
        |    f2(null.asInstanceOf[VCI])  +
        |npe(f2(  n1.asInstanceOf[VCI])) + // SI-8097
        |    f2(  n2.asInstanceOf[VCI])  +
        |npe(f2(  n3.asInstanceOf[VCI])) + // SI-8097
        |    f2(               n4[VCI])  + // "null"
        |"-"                             +
        |    f2(null.asInstanceOf[Unit]) +
        |    f2(  n1.asInstanceOf[Unit]) +
        |    f2(  n2.asInstanceOf[Unit]) +
        |    f2(  n3.asInstanceOf[Unit]) +
        |    f2(               n4[Unit]) + // "null"
        |"-"                             +
        |    f3(null.asInstanceOf[Int])  +
        |    f3(  n1.asInstanceOf[Int])  +
        |    f3(  n2.asInstanceOf[Int])  +
        |    f3(  n3.asInstanceOf[Int])  +
        |    f3(               n4[Int])  + // "null"
        |"-"                             +
        |    f3(null.asInstanceOf[VCI])  +
        |npe(f3(  n1.asInstanceOf[VCI])) + // SI-8097
        |    f3(  n2.asInstanceOf[VCI])  +
        |npe(f3(  n3.asInstanceOf[VCI])) + // SI-8097
        |    f3(               n4[VCI])  + // "null"
        |"-"                             +
        |    f3(null.asInstanceOf[Unit]) +
        |    f3(  n1.asInstanceOf[Unit]) +
        |    f3(  n2.asInstanceOf[Unit]) +
        |    f3(  n3.asInstanceOf[Unit]) +
        |    f3(               n4[Unit]) + // "null"
        |"-"                             +
        |    f4(null.asInstanceOf[Int])  +
        |    f4(  n1.asInstanceOf[Int])  +
        |    f4(  n2.asInstanceOf[Int])  +
        |    f4(  n3.asInstanceOf[Int])  +
        |    f4(               n4[Int])  +
        |"-"                             +
        |    f5(null.asInstanceOf[VCI])  +
        |npe(f5(  n1.asInstanceOf[VCI])) + // SI-8097
        |    f5(  n2.asInstanceOf[VCI])  +
        |npe(f5(  n3.asInstanceOf[VCI])) + // SI-8097
        |npe(f5(               n4[VCI])) + // SI-8097
        |"-"                             +
        |    f6(null.asInstanceOf[Unit]) +
        |    f6(  n1.asInstanceOf[Unit]) +
        |    f6(  n2.asInstanceOf[Unit]) +
        |    f6(  n3.asInstanceOf[Unit]) +
        |    f6(               n4[Unit])   // "null"
      """.stripMargin

    assertEquals(run[String](code),
      "0000null-0npe0npenull-()()()()null-0000null-0npe0npenull-()()()()null-0000null-0npe0npenull-()()()()null-00000-0npe0npenpe-()()()()null")
  }
}