Drop "serialising" Function1. It's easily fallible

librarymanagement/src/main/datatype/librarymanagement.json

@@ -315,10 +315,7 @@
             "For example, if `remapVersion = v => \"2.10\"` and the binary version is \"2.9.2\" or \"2.10\",",
             "the module is cross-versioned with \"2.10\"."
           ],
-          "type": "record",
+          "type": "record"
-          "fields": [
-            { "name": "remapVersion", "type": "Function1[String, String]" }
-          ]
         },
         {
           "name": "Full",
@@ -329,9 +326,6 @@
             "Cross-versions a module with the result of applying `remapVersion` to the full version.",
             "For example, if `remapVersion = v => \"2.10\"` and the full version is \"2.9.2\" or \"2.10.3\",",
             "the module is cross-versioned with \"2.10\"."
-          ],
-          "fields": [
-            { "name": "remapVersion", "type": "Function1[String, String]" }
           ]
         }
       ],

librarymanagement/src/main/scala/sbt/internal/librarymanagement/formats/Function1Format.scala

@@ -1,8 +0,0 @@
-package sbt.internal.librarymanagement.formats
-
-import sjsonnew._
-
-trait Function1Format { self: BasicJsonProtocol =>
-  implicit def Function1Format[T, U]: JsonFormat[T => U] =
-    project(MyCrazyReferences.referenced _, (ref: String) => MyCrazyReferences(ref, classOf[T => U]))
-}

librarymanagement/src/main/scala/sbt/librarymanagement/CrossVersion.scala

@@ -13,25 +13,10 @@ abstract class CrossVersionFunctions {
   val TransitionSbtVersion = CrossVersionUtil.TransitionSbtVersion
 
   /** Cross-versions a module with the full version (typically the full Scala version). */
-  def full: CrossVersion = new Full(idStringFun)
+  def full: CrossVersion = new Full()
-
-  /**
-   * Cross-versions a module with the result of applying `remapVersion` to the full version
-   * (typically the full Scala version).  See also [[sbt.librarymanagement.CrossVersion.Full]].
-   */
-  def fullMapped(remapVersion: String => String): CrossVersion = new Full(remapVersion)
 
   /** Cross-versions a module with the binary version (typically the binary Scala version).  */
-  def binary: CrossVersion = new Binary(idStringFun)
+  def binary: CrossVersion = new Binary()
-
-  /**
-   * Cross-versions a module with the result of applying `remapVersion` to the binary version
-   * (typically the binary Scala version).  See also [[sbt.librarymanagement.CrossVersion.Binary]].
-   */
-  def binaryMapped(remapVersion: String => String): CrossVersion = new Binary(remapVersion)
-
-  private[this] def idFun[T]: T => T = x => x
-  private[this] val idStringFun = idFun[String]
 
   private[sbt] def append(s: String): Option[String => String] = Some(x => crossName(x, s))
 
@@ -43,8 +28,8 @@ abstract class CrossVersionFunctions {
   def apply(cross: CrossVersion, fullVersion: String, binaryVersion: String): Option[String => String] =
     cross match {
       case _: Disabled => None
-      case b: Binary   => append(b.remapVersion(binaryVersion))
+      case _: Binary   => append(binaryVersion)
-      case f: Full     => append(f.remapVersion(fullVersion))
+      case _: Full     => append(fullVersion)
     }
 
   /** Constructs the cross-version function defined by `module` and `is`, if one is configured. */

librarymanagement/src/main/scala/sbt/librarymanagement/ModuleID.scala

@@ -47,9 +47,6 @@ abstract class ModuleIDExtra {
   @deprecated("Use `cross(CrossVersion)`, the variant accepting a CrossVersion value constructed by a member of the CrossVersion object instead.", "0.12.0")
   def cross(v: Boolean): ModuleID = cross(if (v) CrossVersion.binary else Disabled())
 
-  @deprecated("Use `cross(CrossVersion)`, the variant accepting a CrossVersion value constructed by a member of the CrossVersion object instead.", "0.12.0")
-  def cross(v: Boolean, verRemap: String => String): ModuleID = cross(if (v) CrossVersion.binaryMapped(verRemap) else Disabled())
-
   /** Specifies the cross-version behavior for this module.  See [CrossVersion] for details.*/
   def cross(v: CrossVersion): ModuleID = copy(crossVersion = v)
 

project/DatatypeConfig.scala

@@ -20,9 +20,6 @@ object DatatypeConfig {
   val myCodecs: PartialFunction[String, TpeRef => List[String]] = {
     case "java.util.Date" => { _ => "sbt.internal.librarymanagement.formats.DateFormat" :: Nil }
 
-    case "Function1" =>
-      { tpe => "sbt.internal.librarymanagement.formats.Function1Format" :: twoArgs(tpe).flatMap(getFormats) }
-
     case "scala.xml.NodeSeq" => { _ => "sbt.internal.librarymanagement.formats.NodeSeqFormat" :: Nil }
 
     case "org.apache.ivy.plugins.resolver.DependencyResolver" =>