From bff86367607a713288a939639a654802349d1067 Mon Sep 17 00:00:00 2001 From: Adriaan Moors Date: Wed, 18 Feb 2015 12:46:21 -0800 Subject: Use if/then/else to avoid box(unbox(_)) --- src/library/scala/reflect/ClassTag.scala | 29 ++++++++++++++--------------- test/junit/scala/reflect/ClassTag.scala | 29 +++++++++++++++++++++++++++++ 2 files changed, 43 insertions(+), 15 deletions(-) create mode 100644 test/junit/scala/reflect/ClassTag.scala diff --git a/src/library/scala/reflect/ClassTag.scala b/src/library/scala/reflect/ClassTag.scala index b9b4772870..9dd96183da 100644 --- a/src/library/scala/reflect/ClassTag.scala +++ b/src/library/scala/reflect/ClassTag.scala @@ -69,21 +69,20 @@ trait ClassTag[T] extends ClassManifestDeprecatedApis[T] with Equals with Serial * `SomeExtractor(...)` is turned into `ct(SomeExtractor(...))` if `T` in `SomeExtractor.unapply(x: T)` * is uncheckable, but we have an instance of `ClassTag[T]`. */ - def unapply(x: Any): Option[T] = x match { - case null => None - case x: Byte => unapplyImpl(x, classOf[Byte]) // erases to: if (x instanceof Byte) unapplyImpl(BoxesRunTime.boxToByte(BoxesRunTime.unboxToByte(x)), Byte.TYPE) - case x: Short => unapplyImpl(x, classOf[Short]) - case x: Char => unapplyImpl(x, classOf[Char]) - case x: Int => unapplyImpl(x, classOf[Int]) - case x: Long => unapplyImpl(x, classOf[Long]) - case x: Float => unapplyImpl(x, classOf[Float]) - case x: Double => unapplyImpl(x, classOf[Double]) - case x: Boolean => unapplyImpl(x, classOf[Boolean]) - case x: Unit => unapplyImpl(x, classOf[Unit]) - // TODO: move this next case up and remove the redundant check in unapplyImpl? - case _ if runtimeClass isInstance x => Some(x.asInstanceOf[T]) - case _ => None - } + def unapply(x: Any): Option[T] = + if (null != x && ( + (runtimeClass.isInstance(x)) + || (x.isInstanceOf[Byte] && runtimeClass.isAssignableFrom(classOf[Byte])) + || (x.isInstanceOf[Short] && runtimeClass.isAssignableFrom(classOf[Short])) + || (x.isInstanceOf[Char] && runtimeClass.isAssignableFrom(classOf[Char])) + || (x.isInstanceOf[Int] && runtimeClass.isAssignableFrom(classOf[Int])) + || (x.isInstanceOf[Long] && runtimeClass.isAssignableFrom(classOf[Long])) + || (x.isInstanceOf[Float] && runtimeClass.isAssignableFrom(classOf[Float])) + || (x.isInstanceOf[Double] && runtimeClass.isAssignableFrom(classOf[Double])) + || (x.isInstanceOf[Boolean] && runtimeClass.isAssignableFrom(classOf[Boolean])) + || (x.isInstanceOf[Unit] && runtimeClass.isAssignableFrom(classOf[Unit]))) + ) Some(x.asInstanceOf[T]) + else None // TODO: deprecate overloads in 2.12.0, remove in 2.13.0 def unapply(x: Byte) : Option[T] = unapplyImpl(x, classOf[Byte]) diff --git a/test/junit/scala/reflect/ClassTag.scala b/test/junit/scala/reflect/ClassTag.scala new file mode 100644 index 0000000000..90cc981fc1 --- /dev/null +++ b/test/junit/scala/reflect/ClassTag.scala @@ -0,0 +1,29 @@ +package scala.reflect + +import org.junit.Test +import org.junit.Assert._ +import org.junit.runner.RunWith +import org.junit.runners.JUnit4 + +import scala.tools.testing.AssertUtil._ + +class Misc + +@RunWith(classOf[JUnit4]) +class ClassTagTest { + def checkNotString[A: ClassTag](a: Any) = a match { case x: String => false case x: A => true case _ => false } + def checkNotInt[A: ClassTag](a: Any) = a match { case x: Int => false case x: A => true case _ => false } + def checkNotLong[A: ClassTag](a: Any) = a match { case x: Long => false case x: A => true case _ => false } + + @Test def checkMisc = assertTrue(checkNotString[Misc](new Misc)) + @Test def checkString = assertTrue(checkNotInt[String] ("woele")) + @Test def checkByte = assertTrue(checkNotInt[Byte] (0.toByte)) + @Test def checkShort = assertTrue(checkNotInt[Short] (0.toShort)) + @Test def checkChar = assertTrue(checkNotInt[Char] (0.toChar)) + @Test def checkInt = assertTrue(checkNotLong[Int] (0.toInt)) + @Test def checkLong = assertTrue(checkNotInt[Long] (0.toLong)) + @Test def checkFloat = assertTrue(checkNotInt[Float] (0.toFloat)) + @Test def checkDouble = assertTrue(checkNotInt[Double] (0.toDouble)) + @Test def checkBoolean = assertTrue(checkNotInt[Boolean](false)) + @Test def checkUnit = assertTrue(checkNotInt[Unit] ({})) +} \ No newline at end of file -- cgit v1.2.3