Remove some compile warnings

librarymanagement/src/main/scala/sbt/internal/librarymanagement/IvyActions.scala

@@ -21,7 +21,6 @@ import sbt.util.{ Logger, ShowLines }
 import sbt.internal.util.{ SourcePosition, LinePosition, RangePosition, LineRange }
 import sbt.librarymanagement._
 import sbt.internal.librarymanagement.syntax._
-import sbt.internal.librarymanagement._
 
 final class DeliverConfiguration(val deliverIvyPattern: String, val status: String, val configurations: Option[Vector[Configuration]], val logging: UpdateLogging)
 final class PublishConfiguration(val ivyFile: Option[File], val resolverName: String, val artifacts: Map[Artifact, File], val checksums: Vector[String], val logging: UpdateLogging,

librarymanagement/src/main/scala/sbt/internal/librarymanagement/ivyint/CachedResolutionResolveEngine.scala

@@ -123,13 +123,13 @@ private[sbt] class CachedResolutionResolveCache(fileToStore: File => CacheStore)
     }
   def extractOverrides(md0: ModuleDescriptor): Vector[IvyOverride] =
     {
-      import scala.collection.JavaConversions._
-      (md0.getAllDependencyDescriptorMediators.getAllRules).toSeq.toVector sortBy {
+      import scala.collection.JavaConverters._
+      md0.getAllDependencyDescriptorMediators.getAllRules.asScala.toSeq.toVector sortBy {
         case (k, v) =>
           k.toString
       } collect {
         case (k: MapMatcher, v: OverrideDependencyDescriptorMediator) =>
-          val attr: Map[Any, Any] = k.getAttributes.toMap
+          val attr: Map[Any, Any] = k.getAttributes.asScala.toMap
           val module = IvyModuleId.newInstance(attr(IvyPatternHelper.ORGANISATION_KEY).toString, attr(IvyPatternHelper.MODULE_KEY).toString)
           val pm = k.getPatternMatcher
           IvyOverride(module, pm, v)

librarymanagement/src/main/scala/sbt/librarymanagement/Credentials.scala

@@ -58,12 +58,12 @@ object Credentials {
   private[this] val UserKeys = List("user", "user.name", "username")
   private[this] val PasswordKeys = List("password", "pwd", "pass", "passwd")
 
-  import collection.JavaConversions._
+  import collection.JavaConverters._
   private[this] def read(from: File): Map[String, String] =
     {
       val properties = new java.util.Properties
       IO.load(properties, from)
-      properties.map { case (k, v) => (k.toString, v.toString.trim) }.toMap
+      properties.asScala.map { case (k, v) => (k.toString, v.toString.trim) }.toMap
     }
 }
 

librarymanagement/src/main/scala/sbt/librarymanagement/DefaultLibraryManagement.scala

@@ -2,7 +2,6 @@ package sbt
 package librarymanagement
 
 import java.io.File
-import scala.util.Try
 import sbt.internal.librarymanagement._
 import sbt.util.Logger
 import sbt.io.Hash
@@ -61,7 +60,7 @@ class DefaultLibraryManagement(ivyConfiguration: IvyConfiguration, log: Logger)
     log.debug(s"Attempting to fetch ${dependenciesNames(module)}. This operation may fail.")
     IvyActions.updateEither(module, updateConfiguration, UnresolvedWarningConfiguration(), LogicalClock.unknown, None, log) match {
       case Left(unresolvedWarning) =>
-        log.debug("Couldn't retrieve module ${dependenciesNames(module)}.")
+        log.debug(s"Couldn't retrieve module ${dependenciesNames(module)}.")
         None
 
       case Right(updateReport) =>

librarymanagement/src/test/scala/DMSerializationSpec.scala

@@ -6,6 +6,7 @@ import java.io.File
 import sbt.internal._, librarymanagement._, util.UnitSpec
 import scala.json.ast.unsafe._
 import sjsonnew._, support.scalajson.unsafe._
+import org.scalatest.Assertion
 
 import LibraryManagementCodec._
 
@@ -61,11 +62,13 @@ class DMSerializationSpec extends UnitSpec {
   lazy val moduleReportExample =
     ModuleReport(ModuleID("org", "name", "1.0"), Vector.empty, Vector.empty)
 
-  def roundtrip[A: JsonReader: JsonWriter](a: A): Unit =
+  def roundtrip[A: JsonReader: JsonWriter](a: A): Assertion =
     roundtripBuilder(a) { _ shouldBe _ }
-  def roundtripStr[A: JsonReader: JsonWriter](a: A): Unit =
+
+  def roundtripStr[A: JsonReader: JsonWriter](a: A): Assertion =
     roundtripBuilder(a) { _.toString shouldBe _.toString }
-  def roundtripBuilder[A: JsonReader: JsonWriter](a: A)(f: (A, A) => Unit): Unit =
+
+  def roundtripBuilder[A: JsonReader: JsonWriter](a: A)(f: (A, A) => Assertion): Assertion =
     {
       val json = isoString to (Converter toJsonUnsafe a)
       println(json)