Support for enhanced cross build suffix in dependencies. Closes #267

Overloading `%%` for library dependency to allow using a library built
with an alternative version of Scala that is different from the Scala
version used in the current build (but hopefully binary compatible).

This is useful in cases, where the binary build of a dependency with
the exact Scala version isn't yet available but an otherwise binary
compatible build (maybe with a previous Scala release) is available.

ivy/DependencyBuilders.scala

@@ -4,7 +4,7 @@
 package sbt
 package impl
 
-	import StringUtilities.{appendable,nonEmpty}
+import StringUtilities.nonEmpty
 
 trait DependencyBuilders
 {
@@ -27,20 +27,21 @@ trait DependencyBuilders
 
 final class GroupID private[sbt] (groupID: String)
 {
-	def % (artifactID: String) = groupArtifact(artifactID, false)
+	def % (artifactID: String) = groupArtifact(artifactID, None)
-	def %% (artifactID: String) = groupArtifact(artifactID, true)
+	def %% (artifactID: String, crossVersion: String => String = identity) = groupArtifact(artifactID, Some(crossVersion))
-	private def groupArtifact(artifactID: String, cross: Boolean) =
+	def %% (artifactID: String, alternatives: (String, String)*) = groupArtifact(artifactID, Some(Map(alternatives: _*) orElse { case s => s }))
+	private def groupArtifact(artifactID: String, cross: Option[String => String]) =
 	{
 		nonEmpty(artifactID, "Artifact ID")
 		new GroupArtifactID(groupID, artifactID, cross)
 	}
 }
-final class GroupArtifactID private[sbt] (groupID: String, artifactID: String, crossVersion: Boolean)
+final class GroupArtifactID private[sbt] (groupID: String, artifactID: String, crossVersion: Option[String => String])
-{	
+{
 	def % (revision: String): ModuleID =
 	{
 		nonEmpty(revision, "Revision")
-		ModuleID(groupID, artifactID, revision).cross(crossVersion)
+		ModuleID(groupID, artifactID, revision).cross(!crossVersion.isEmpty, crossVersion.getOrElse(identity))
 	}
 }
 final class ModuleIDConfigurable private[sbt] (moduleID: ModuleID)

ivy/Ivy.scala

@@ -314,7 +314,7 @@ private object IvySbt
 		as.map(art => substituteCross(art, cross))
 	def substituteCross(m: ModuleID, cross: String): ModuleID =
 		if(m.crossVersion)
-			m.copy(name = crossName(m.name, cross), explicitArtifacts = substituteCrossA(m.explicitArtifacts, cross))
+			m.copy(name = crossName(m.name, m.crossVersionRemap(cross)), explicitArtifacts = substituteCrossA(m.explicitArtifacts, cross))
 		else
 			m
 		

ivy/IvyActions.scala

@@ -205,7 +205,7 @@ object IvyActions
 		report.allMissing flatMap { case (_, mod, art) => art.classifier.map { c => (restrictedCopy(mod, false), c) } } groupBy(_._1) map { case (mod, pairs) => (mod, pairs.map(_._2).toSet) }
 
 	private[this] def restrictedCopy(m: ModuleID, confs: Boolean) =
-		ModuleID(m.organization, m.name, m.revision, crossVersion = m.crossVersion, extraAttributes = m.extraAttributes, configurations = if(confs) m.configurations else None)
+		ModuleID(m.organization, m.name, m.revision, crossVersion = m.crossVersion, crossVersionRemap = m.crossVersionRemap, extraAttributes = m.extraAttributes, configurations = if(confs) m.configurations else None)
 	private[this] def resolve(logging: UpdateLogging.Value)(ivy: Ivy, module: DefaultModuleDescriptor, defaultConf: String): (ResolveReport, Option[ResolveException]) =
 	{
 		val resolveOptions = new ResolveOptions
@@ -268,4 +268,4 @@ object IvyActions
 		}
 
 }
-final class ResolveException(val messages: Seq[String], val failed: Seq[ModuleID]) extends RuntimeException(messages.mkString("\n"))
+final class ResolveException(val messages: Seq[String], val failed: Seq[ModuleID]) extends RuntimeException(messages.mkString("\n"))

ivy/IvyInterface.scala

@@ -9,14 +9,14 @@ import scala.xml.NodeSeq
 import org.apache.ivy.plugins.resolver.{DependencyResolver, IBiblioResolver}
 import org.apache.ivy.util.url.CredentialsStore
 
-final case class ModuleID(organization: String, name: String, revision: String, configurations: Option[String] = None, isChanging: Boolean = false, isTransitive: Boolean = true, explicitArtifacts: Seq[Artifact] = Nil, exclusions: Seq[ExclusionRule] = Nil, extraAttributes: Map[String,String] = Map.empty, crossVersion: Boolean = false)
+final case class ModuleID(organization: String, name: String, revision: String, configurations: Option[String] = None, isChanging: Boolean = false, isTransitive: Boolean = true, explicitArtifacts: Seq[Artifact] = Nil, exclusions: Seq[ExclusionRule] = Nil, extraAttributes: Map[String,String] = Map.empty, crossVersion: Boolean = false, crossVersionRemap: String => String = identity)
 {
 	override def toString =
 		organization + ":" + name + ":" + revision +
 		(configurations match { case Some(s) => ":" + s; case None => "" }) +
 		(if(extraAttributes.isEmpty) "" else " " + extraString)
 	def extraString = extraAttributes.map { case (k,v) => k + "=" + v } mkString("(",", ",")")
-	def cross(v: Boolean) = copy(crossVersion = v)
+	def cross(v: Boolean, verRemap: String => String = identity) = copy(crossVersion = v, crossVersionRemap = verRemap)
 	// () required for chaining
 	def notTransitive() = intransitive()
 	def intransitive() = copy(isTransitive = false)
@@ -282,7 +282,7 @@ object Resolver
 		def resolveAll(patterns: Seq[String]) = patterns.map(p => resolvePattern(base, p))
 		Patterns(resolveAll(basePatterns.ivyPatterns), resolveAll(basePatterns.artifactPatterns), basePatterns.isMavenCompatible)
 	}
-	private[sbt] def resolvePattern(base: String, pattern: String): String = 
+	private[sbt] def resolvePattern(base: String, pattern: String): String =
 	{
 		val normBase = base.replace('\\', '/')
 		if(normBase.endsWith("/") || pattern.startsWith("/")) normBase + pattern else normBase + "/" + pattern
@@ -423,14 +423,14 @@ object Artifact
 	{
 			import artifact._
 		val classifierStr = classifier match { case None => ""; case Some(c) => "-" + c }
-		val base = if(module.crossVersion) IvySbt.crossName(artifact.name, scalaVersion) else artifact.name
+		val base = if(module.crossVersion) IvySbt.crossName(artifact.name, module.crossVersionRemap(scalaVersion)) else artifact.name
 		base + "-" + module.revision + classifierStr + "." + artifact.extension
 	}
 	def cross(enable: Boolean, scalaVersion: String): String = if(enable) "_" + scalaVersion else ""
 
 	val classifierConfMap = Map(SourceClassifier -> Sources, DocClassifier -> Docs)
 	val classifierTypeMap = Map(SourceClassifier -> SourceType, DocClassifier -> DocType)
-	def classifierConf(classifier: String): Configuration = classifierConfMap.getOrElse(classifier, Optional)	
+	def classifierConf(classifier: String): Configuration = classifierConfMap.getOrElse(classifier, Optional)
 	def classifierType(classifier: String): String = classifierTypeMap.getOrElse(classifier, DefaultType)
 	def classified(name: String, classifier: String): Artifact =
 		Artifact(name, classifierType(classifier), DefaultExtension, Some(classifier), classifierConf(classifier) :: Nil, None)
@@ -440,4 +440,4 @@ object ModuleConfiguration
 {
 	def apply(org: String, resolver: Resolver): ModuleConfiguration = apply(org, "*", "*", resolver)
 	def apply(org: String, name: String, resolver: Resolver): ModuleConfiguration = ModuleConfiguration(org, name, "*", resolver)
-}
+}