Merge pull request #13 from KamchatkaLtd/scala-2.12

Move to Scala 2.12

.travis.yml

@@ -1,7 +1,6 @@
 language: scala
 scala:
-   - 2.11.7
-   - 2.11.8
+   - 2.12.8
 
 script:
   - sbt clean coverage test

build.sbt

@@ -2,11 +2,11 @@ name := "prio_queues"
 
 version := "1.0"
 
-scalaVersion := "2.11.7"
+scalaVersion := "2.12.8"
 
 libraryDependencies ++= Seq(
-  "org.specs2" %% "specs2-core" % "3.5" % "test",
-  "org.specs2" %% "specs2-scalacheck" % "3.5" % "test"
+  "org.specs2" %% "specs2-core" % "4.3.4" % "test",
+  "org.specs2" %% "specs2-scalacheck" % "4.3.4" % "test"
 )
 
 resolvers += "scalaz-bintray" at "http://dl.bintray.com/scalaz/releases"

project/plugins.sbt

@@ -1 +1,3 @@
-addSbtPlugin("org.scoverage" % "sbt-scoverage" % "1.1.0")
+addSbtPlugin("org.scoverage" % "sbt-scoverage" % "1.5.1")
+
+addSbtPlugin("org.scoverage" % "sbt-coveralls" % "1.2.2")

src/main/scala/okasaki/misc/Exercises.scala

@@ -1,7 +1,7 @@
 package okasaki.misc
 
 /**
- * Copyright (C) 2015 Kamchatka Ltd
+ * Copyright (C) 2015-2019 Kamchatka Ltd
  */
 object Exercises {
 
@@ -21,7 +21,7 @@ object Exercises {
   }
 
   // ex 2.5b
-  def almostComplete[E](x: E, n: Int) = {
+  def almostComplete[E](x: E, n: Int): BinaryTree[E] = {
     def create2(x: E, m: Int): (BinaryTree[E], BinaryTree[E]) = m match {
       case 0 => (Empty, SubBinaryTree(Empty, x, Empty))
       case mm if mm > 0 =>

src/test/scala/okasaki/RandomAccessListSpec.scala

@@ -1,13 +1,13 @@
 package okasaki
 
-import org.scalacheck.Arbitrary
+import org.scalacheck.{Arbitrary, Gen}
 import org.scalacheck.Arbitrary._
 import org.scalacheck.Gen.choose
 import org.specs2.ScalaCheck
 import org.specs2.mutable.Specification
 
 /**
- * Copyright (C) 2015 Kamchatka Ltd
+ * Copyright (C) 2015-2019 Kamchatka Ltd
  */
 abstract class RandomAccessListSpec[E, RL, RAL <: RandomAccessList[E, RL]](val list: RAL)
   extends Specification with ScalaCheck {
@@ -51,13 +51,14 @@ abstract class RandomAccessListSpec[E, RL, RAL <: RandomAccessList[E, RL]](val l
     }
 
     "Random update is non-breaking" ! prop {
-      (xs: ListWithTwoIndices, e: E) => xs.distinct ==>  {
-        val ListWithTwoIndices(l, i, j) = xs
+      (xs: ListWithTwoIndices, e: E) =>
+        xs.distinct ==> {
+          val ListWithTwoIndices(l, i, j) = xs
 
-        val xs1 = list.update(i, e, fromList(l))
+          val xs1 = list.update(i, e, fromList(l))
 
-        list.lookup(j, xs1) === l(j)
-      }
+          list.lookup(j, xs1) === l(j)
+        }
     }
   }
 
@@ -71,13 +72,19 @@ abstract class RandomAccessListSpec[E, RL, RAL <: RandomAccessList[E, RL]](val l
   lazy implicit val listWithIndex: Arbitrary[ListWithIndex] =
     Arbitrary(for {
       xs <- arbitrary[List[E]]
-      i <- choose(0, xs.size - 1)
+      if xs.nonEmpty
+      i <- indexOf(xs)
     } yield ListWithIndex(xs, i))
 
   lazy implicit val listWithTwoDistinctIndexes: Arbitrary[ListWithTwoIndices] =
     Arbitrary(for {
       xs <- arbitrary[List[E]]
-      i <- choose(0, xs.size - 1)
-      j <- choose(0, xs.size - 1)
+      if xs.length >= 2
+      i <- indexOf(xs)
+      j <- indexOf(xs)
+      if i != j
     } yield ListWithTwoIndices(xs, i, j))
+
+  private def indexOf(xs: List[E]): Gen[Int] =
+    choose(0, Math.max(0, xs.size - 1))
 }

src/test/scala/okasaki/heaps/HeapWithDeletionSpec.scala

@@ -1,16 +1,16 @@
 package okasaki.heaps
 
 import okasaki.{HeapSpec, HeapWithDeletion, IntElements}
-import org.scalacheck.Arbitrary
+import org.scalacheck.{Arbitrary, Gen}
 import org.scalacheck.Arbitrary._
 import org.scalacheck.Gen._
 
 /**
- * Copyright (C) 2015 Kamchatka Ltd
+ * Copyright (C) 2015-2019 Kamchatka Ltd
  */
 class HeapWithDeletionSpec
   extends HeapSpec[Int, HeapWithDeletion[Int, SkewBinomialHeap[Int]]]
-  with IntElements {
+    with IntElements {
 
   def empty = new HeapWithDeletion(new SkewBinomialHeap[Int]())
 
@@ -38,6 +38,10 @@ class HeapWithDeletionSpec
   lazy implicit val listWithElement: Arbitrary[ListWithElement] =
     Arbitrary(for {
       xs <- arbitrary[List[Int]]
-      i <- choose(0, xs.size - 1)
+      if xs.nonEmpty
+      i <- indexIn(xs)
     } yield ListWithElement(xs, xs(i)))
+
+  private def indexIn(xs: List[Int]): Gen[Int] =
+    choose(0, Math.max(0, xs.size - 1))
 }

src/test/scala/okasaki/misc/ExerciseSpec.scala

@@ -5,7 +5,7 @@ import org.specs2.ScalaCheck
 import org.specs2.mutable.Specification
 
 /**
- * Copyright (C) 2015 Kamchatka Ltd
+ * Copyright (C) 2015-2019 Kamchatka Ltd
  */
 class ExerciseSpec extends Specification with ScalaCheck {
   "Complete set" should {
@@ -22,5 +22,5 @@ class ExerciseSpec extends Specification with ScalaCheck {
     }
   }
 
-  implicit val sizes = Arbitrary(Gen.chooseNum(0, 30))
+  implicit val sizes: Arbitrary[Int] = Arbitrary(Gen.chooseNum(0, 30))
 }