diff --git a/librarymanagement/src/main/scala/sbt/internal/librarymanagement/cross/CrossVersionUtil.scala b/librarymanagement/src/main/scala/sbt/internal/librarymanagement/cross/CrossVersionUtil.scala
index cebe00ac5..b9d4cc2dd 100644
--- a/librarymanagement/src/main/scala/sbt/internal/librarymanagement/cross/CrossVersionUtil.scala
+++ b/librarymanagement/src/main/scala/sbt/internal/librarymanagement/cross/CrossVersionUtil.scala
@@ -13,79 +13,81 @@ object CrossVersionUtil {
   val TransitionSbtVersion = "0.12"
 
   def isFull(s: String): Boolean = (s == trueString) || (s == fullString)
+
   def isDisabled(s: String): Boolean =
     (s == falseString) || (s == noneString) || (s == disabledString)
+
   def isBinary(s: String): Boolean = (s == binaryString)
 
-  private lazy val intPattern = """\d{1,10}"""
-  private lazy val basicVersion = """(""" + intPattern + """)\.(""" + intPattern + """)\.(""" + intPattern + """)"""
+  private val longPattern = """\d{1,19}"""
+  private val basicVersion = raw"""($longPattern)\.($longPattern)\.($longPattern)"""
+  private val ReleaseV = raw"""$basicVersion(-\d+)?""".r
+  private val BinCompatV = raw"""$basicVersion-bin(-.*)?""".r
+  private val CandidateV = raw"""$basicVersion(-RC\d+)""".r
+  private val NonReleaseV_n = raw"""$basicVersion([-\w]*)""".r // 0-n word suffixes, with leading dashes
+  private val NonReleaseV_1 = raw"""$basicVersion(-\w+)""".r // 1 word suffix, after a dash
+  private[sbt] val PartialVersion = raw"""($longPattern)\.($longPattern)(?:\..+)?""".r
 
   private[sbt] def isSbtApiCompatible(v: String): Boolean = sbtApiVersion(v).isDefined
 
   /**
    * Returns sbt binary interface x.y API compatible with the given version string v.
    * RCs for x.y.0 are considered API compatible.
-   * Compatibile versions include 0.12.0-1 and 0.12.0-RC1 for Some(0, 12).
+   * Compatible versions include 0.12.0-1 and 0.12.0-RC1 for Some(0, 12).
    */
-  private[sbt] def sbtApiVersion(v: String): Option[(Int, Int)] = {
-    val ReleaseV = (basicVersion + """(-\d+)?""").r
-    val CandidateV = (basicVersion + """(-RC\d+)""").r
-    val NonReleaseV = (basicVersion + """([-\w+]*)""").r
-    v match {
-      case ReleaseV(x, y, z, ht)                   => Some((x.toInt, y.toInt))
-      case CandidateV(x, y, z, ht)                 => Some((x.toInt, y.toInt))
-      case NonReleaseV(x, y, z, ht) if z.toInt > 0 => Some((x.toInt, y.toInt))
-      case _                                       => None
-    }
+  private[sbt] def sbtApiVersion(v: String): Option[(Long, Long)] = v match {
+    case ReleaseV(x, y, _, _)                     => Some(sbtApiVersion(x.toLong, y.toLong))
+    case CandidateV(x, y, _, _)                   => Some(sbtApiVersion(x.toLong, y.toLong))
+    case NonReleaseV_n(x, y, z, _) if z.toInt > 0 => Some(sbtApiVersion(x.toLong, y.toLong))
+    case _                                        => None
   }
+
+  private def sbtApiVersion(x: Long, y: Long) = {
+    // Prior to sbt 1 the "sbt api version" was the X.Y in the X.Y.Z version.
+    // For example for sbt 0.13.x releases, the sbt api version is 0.13
+    // As of sbt 1 it is now X.0.
+    // This means, for example, that all versions of sbt 1.x have sbt api version 1.0
+    if (x > 0) (x, 0L) else (x, y)
+  }
+
   private[sbt] def isScalaApiCompatible(v: String): Boolean = scalaApiVersion(v).isDefined
 
   /**
    * Returns Scala binary interface x.y API compatible with the given version string v.
-   * Compatibile versions include 2.10.0-1 and 2.10.1-M1 for Some(2, 10), but not 2.10.0-RC1.
+   * Compatible versions include 2.10.0-1 and 2.10.1-M1 for Some(2, 10), but not 2.10.0-RC1.
    */
-  private[sbt] def scalaApiVersion(v: String): Option[(Int, Int)] = {
-    val ReleaseV = (basicVersion + """(-\d+)?""").r
-    val BinCompatV = (basicVersion + """-bin(-.*)?""").r
-    val NonReleaseV = (basicVersion + """(-\w+)""").r
-    v match {
-      case ReleaseV(x, y, z, ht)                   => Some((x.toInt, y.toInt))
-      case BinCompatV(x, y, z, ht)                 => Some((x.toInt, y.toInt))
-      case NonReleaseV(x, y, z, ht) if z.toInt > 0 => Some((x.toInt, y.toInt))
-      case _                                       => None
-    }
+  private[sbt] def scalaApiVersion(v: String): Option[(Long, Long)] = v match {
+    case ReleaseV(x, y, _, _)                     => Some((x.toLong, y.toLong))
+    case BinCompatV(x, y, _, _)                   => Some((x.toLong, y.toLong))
+    case NonReleaseV_1(x, y, z, _) if z.toInt > 0 => Some((x.toLong, y.toLong))
+    case _                                        => None
   }
-  private[sbt] val PartialVersion =
-    ("""(""" + intPattern + """)\.(""" + intPattern + """)(?:\..+)?""").r
-  private[sbt] def partialVersion(s: String): Option[(Int, Int)] =
+
+  private[sbt] def partialVersion(s: String): Option[(Long, Long)] =
     s match {
-      case PartialVersion(major, minor) => Some((major.toInt, minor.toInt))
+      case PartialVersion(major, minor) => Some((major.toLong, minor.toLong))
       case _                            => None
     }
-  def binaryScalaVersion(full: String): String = {
-    val cutoff =
-      if (full.startsWith("0."))
-        TransitionDottyVersion
-      else
-        TransitionScalaVersion
 
+  def binaryScalaVersion(full: String): String = {
+    val cutoff = if (full.startsWith("0.")) TransitionDottyVersion else TransitionScalaVersion
     binaryVersionWithApi(full, cutoff)(scalaApiVersion)
   }
+
   def binarySbtVersion(full: String): String =
     binaryVersionWithApi(full, TransitionSbtVersion)(sbtApiVersion)
-  private[sbt] def binaryVersion(full: String, cutoff: String): String =
-    binaryVersionWithApi(full, cutoff)(scalaApiVersion)
-  private[this] def isNewer(major: Int, minor: Int, minMajor: Int, minMinor: Int): Boolean =
+
+  private[this] def isNewer(major: Long, minor: Long, minMajor: Long, minMinor: Long): Boolean =
     major > minMajor || (major == minMajor && minor >= minMinor)
+
   private[this] def binaryVersionWithApi(full: String, cutoff: String)(
-      apiVersion: String => Option[(Int, Int)]
+      apiVersion: String => Option[(Long, Long)]
   ): String = {
-    def sub(major: Int, minor: Int) = major + "." + minor
     (apiVersion(full), partialVersion(cutoff)) match {
-      case (Some((major, minor)), None) => sub(major, minor)
+      case (Some((major, minor)), None) => s"$major.$minor"
       case (Some((major, minor)), Some((minMajor, minMinor)))
           if isNewer(major, minor, minMajor, minMinor) =>
-        sub(major, minor)
+        s"$major.$minor"
       case _ => full
     }
   }
diff --git a/librarymanagement/src/main/scala/sbt/librarymanagement/CrossVersionExtra.scala b/librarymanagement/src/main/scala/sbt/librarymanagement/CrossVersionExtra.scala
index 29ef28327..c7e8fecc8 100644
--- a/librarymanagement/src/main/scala/sbt/librarymanagement/CrossVersionExtra.scala
+++ b/librarymanagement/src/main/scala/sbt/librarymanagement/CrossVersionExtra.scala
@@ -76,8 +76,8 @@ abstract class CrossVersionFunctions {
       cross: Option[String => String]
   ): Vector[Artifact] =
     cross match {
-      case None     => artifacts
-      case Some(is) => substituteCrossA(artifacts, cross)
+      case None    => artifacts
+      case Some(_) => substituteCrossA(artifacts, cross)
     }
 
   private[sbt] def applyCross(s: String, fopt: Option[String => String]): String =
@@ -124,34 +124,28 @@ abstract class CrossVersionFunctions {
       m
   }
 
-  @deprecated("Use CrossVersion.isScalaApiCompatible or CrossVersion.isSbtApiCompatible", "0.13.0")
-  def isStable(v: String): Boolean = isScalaApiCompatible(v)
-
-  @deprecated("Use CrossVersion.scalaApiVersion or CrossVersion.sbtApiVersion", "0.13.0")
-  def selectVersion(full: String, binary: String): String = if (isStable(full)) binary else full
-
   def isSbtApiCompatible(v: String): Boolean = CrossVersionUtil.isSbtApiCompatible(v)
 
   /**
    * Returns sbt binary interface x.y API compatible with the given version string v.
    * RCs for x.y.0 are considered API compatible.
-   * Compatibile versions include 0.12.0-1 and 0.12.0-RC1 for Some(0, 12).
+   * Compatible versions include 0.12.0-1 and 0.12.0-RC1 for Some(0, 12).
    */
-  def sbtApiVersion(v: String): Option[(Int, Int)] = CrossVersionUtil.sbtApiVersion(v)
+  def sbtApiVersion(v: String): Option[(Long, Long)] = CrossVersionUtil.sbtApiVersion(v)
 
   def isScalaApiCompatible(v: String): Boolean = CrossVersionUtil.isScalaApiCompatible(v)
 
   /**
    * Returns Scala binary interface x.y API compatible with the given version string v.
-   * Compatibile versions include 2.10.0-1 and 2.10.1-M1 for Some(2, 10), but not 2.10.0-RC1.
+   * Compatible versions include 2.10.0-1 and 2.10.1-M1 for Some(2, 10), but not 2.10.0-RC1.
    */
-  def scalaApiVersion(v: String): Option[(Int, Int)] = CrossVersionUtil.scalaApiVersion(v)
+  def scalaApiVersion(v: String): Option[(Long, Long)] = CrossVersionUtil.scalaApiVersion(v)
 
   /** Regular expression that extracts the major and minor components of a version into matched groups 1 and 2.*/
   val PartialVersion = CrossVersionUtil.PartialVersion
 
   /** Extracts the major and minor components of a version string `s` or returns `None` if the version is improperly formatted. */
-  def partialVersion(s: String): Option[(Int, Int)] = CrossVersionUtil.partialVersion(s)
+  def partialVersion(s: String): Option[(Long, Long)] = CrossVersionUtil.partialVersion(s)
 
   /**
    * Computes the binary Scala version from the `full` version.
@@ -164,9 +158,4 @@ abstract class CrossVersionFunctions {
    * Full sbt versions earlier than [[sbt.librarymanagement.CrossVersion.TransitionSbtVersion]] are returned as is.
    */
   def binarySbtVersion(full: String): String = CrossVersionUtil.binarySbtVersion(full)
-
-  @deprecated("Use CrossVersion.scalaApiVersion or CrossVersion.sbtApiVersion", "0.13.0")
-  def binaryVersion(full: String, cutoff: String): String =
-    CrossVersionUtil.binaryVersion(full, cutoff)
-
 }
diff --git a/librarymanagement/src/test/scala/CrossVersionTest.scala b/librarymanagement/src/test/scala/CrossVersionTest.scala
index 835ad1058..b65c9a11b 100644
--- a/librarymanagement/src/test/scala/CrossVersionTest.scala
+++ b/librarymanagement/src/test/scala/CrossVersionTest.scala
@@ -1,156 +1,242 @@
 package sbt.librarymanagement
 
 import sbt.internal.util.UnitSpec
+import CrossVersion._
 
 class CrossVersionTest extends UnitSpec {
-  "Cross version" should "return sbt API for xyz as None" in {
-    CrossVersion.sbtApiVersion("xyz") shouldBe None
+  "sbtApiVersion" should "for xyz return None" in {
+    sbtApiVersion("xyz") shouldBe None
   }
-  it should "return sbt API for 0.12 as None" in {
-    CrossVersion.sbtApiVersion("0.12") shouldBe None
+  it should "for 0.12 return None" in {
+    sbtApiVersion("0.12") shouldBe None
   }
-  it should "return sbt API for 0.12.0-SNAPSHOT as None" in {
-    CrossVersion.sbtApiVersion("0.12.0-SNAPSHOT") shouldBe None
+  it should "for 0.12.0-SNAPSHOT return None" in {
+    sbtApiVersion("0.12.0-SNAPSHOT") shouldBe None
   }
-  it should "return sbt API for 0.12.0-RC1 as Some((0, 12))" in {
-    CrossVersion.sbtApiVersion("0.12.0-RC1") shouldBe Some((0, 12))
+  it should "for 0.12.0-RC1 return Some((0, 12))" in {
+    sbtApiVersion("0.12.0-RC1") shouldBe Some((0, 12))
   }
-  it should "return sbt API for 0.12.0 as Some((0, 12))" in {
-    CrossVersion.sbtApiVersion("0.12.0") shouldBe Some((0, 12))
+  it should "for 0.12.0 return Some((0, 12))" in {
+    sbtApiVersion("0.12.0") shouldBe Some((0, 12))
   }
-  it should "return sbt API for 0.12.1-SNAPSHOT as Some((0, 12))" in {
-    CrossVersion.sbtApiVersion("0.12.1-SNAPSHOT") shouldBe Some((0, 12))
+  it should "for 0.12.1-SNAPSHOT return Some((0, 12))" in {
+    sbtApiVersion("0.12.1-SNAPSHOT") shouldBe Some((0, 12))
   }
-  it should "return sbt API for 0.12.1-RC1 as Some((0, 12))" in {
-    CrossVersion.sbtApiVersion("0.12.1-RC1") shouldBe Some((0, 12))
+  it should "for 0.12.1-RC1 return Some((0, 12))" in {
+    sbtApiVersion("0.12.1-RC1") shouldBe Some((0, 12))
   }
-  it should "return sbt API for 0.12.1 as Some((0, 12))" in {
-    CrossVersion.sbtApiVersion("0.12.1") shouldBe Some((0, 12))
+  it should "for 0.12.1 return Some((0, 12))" in {
+    sbtApiVersion("0.12.1") shouldBe Some((0, 12))
   }
-  it should "return sbt API compatibility for 0.12.0-M1 as false" in {
-    CrossVersion.isSbtApiCompatible("0.12.0-M1") shouldBe false
+  it should "for 1.0.0-M6 return None" in {
+    sbtApiVersion("1.0.0-M6") shouldBe None
   }
-  it should "return sbt API compatibility for 0.12.0-RC1 as true" in {
-    CrossVersion.isSbtApiCompatible("0.12.0-RC1") shouldBe true
+  it should "for 1.0.0-RC1 return Some((1, 0))" in {
+    sbtApiVersion("1.0.0-RC1") shouldBe Some((1, 0))
   }
-  it should "return sbt API compatibility for 0.12.1-RC1 as true" in {
-    CrossVersion.isSbtApiCompatible("0.12.1-RC1") shouldBe true
+  it should "for 1.0.0 return Some((1, 0))" in {
+    sbtApiVersion("1.0.0") shouldBe Some((1, 0))
   }
-  it should "return binary sbt version for 0.11.3 as 0.11.3" in {
-    CrossVersion.binarySbtVersion("0.11.3") shouldBe "0.11.3"
+  it should "for 1.0.2-M1 return Some((1, 0))" in {
+    sbtApiVersion("1.0.2-M1") shouldBe Some((1, 0))
   }
-  it should "return binary sbt version for 0.12.0-M1 as 0.12.0-M1" in {
-    CrossVersion.binarySbtVersion("0.12.0-M1") shouldBe "0.12.0-M1"
+  it should "for 1.0.2-RC1 return Some((1, 0))" in {
+    sbtApiVersion("1.0.2-RC1") shouldBe Some((1, 0))
   }
-  it should "return binary sbt version for 0.12.0-RC1 as 0.12" in {
-    CrossVersion.binarySbtVersion("0.12.0-RC1") shouldBe "0.12"
+  it should "for 1.0.2 return Some((1, 0))" in {
+    sbtApiVersion("1.0.2") shouldBe Some((1, 0))
   }
-  it should "return binary sbt version for 0.12.0 as 0.12" in {
-    CrossVersion.binarySbtVersion("0.12.0") shouldBe "0.12"
+  it should "for 1.3.0 return Some((1, 0))" in {
+    sbtApiVersion("1.3.0") shouldBe Some((1, 0))
   }
-  it should "return binary sbt version for 0.12.1-SNAPSHOT as 0.12" in {
-    CrossVersion.binarySbtVersion("0.12.1-SNAPSHOT") shouldBe "0.12"
+  it should "for 1.10.0 return Some((1, 0))" in {
+    sbtApiVersion("1.10.0") shouldBe Some((1, 0))
   }
-  it should "return binary sbt version for 0.12.1-RC1 as 0.12" in {
-    CrossVersion.binarySbtVersion("0.12.1-RC1") shouldBe "0.12"
+  it should "for 2.0.0 return Some((2, 0))" in {
+    sbtApiVersion("2.0.0") shouldBe Some((2, 0))
   }
-  it should "return binary sbt version for 0.12.1 as 0.12" in {
-    CrossVersion.binarySbtVersion("0.12.1") shouldBe "0.12"
+
+  "isSbtApiCompatible" should "for 0.12.0-M1 return false" in {
+    isSbtApiCompatible("0.12.0-M1") shouldBe false
   }
-  it should "return Scala API for xyz as None" in {
-    CrossVersion.scalaApiVersion("xyz") shouldBe None
+  it should "for 0.12.0-RC1 return true" in {
+    isSbtApiCompatible("0.12.0-RC1") shouldBe true
   }
-  it should "return Scala API for 2.10 as None" in {
-    CrossVersion.scalaApiVersion("2.10") shouldBe None
+  it should "for 0.12.1-RC1 return true" in {
+    isSbtApiCompatible("0.12.1-RC1") shouldBe true
   }
-  it should "return Scala API for 2.10.0-SNAPSHOT as None" in {
-    CrossVersion.scalaApiVersion("2.10.0-SNAPSHOT") shouldBe None
+  it should "for 1.0.0-M6 return false" in {
+    isSbtApiCompatible("1.0.0-M6") shouldBe false
   }
-  it should "return Scala API for 2.10.0-RC1 as None" in {
-    CrossVersion.scalaApiVersion("2.10.0-RC1") shouldBe None
+  it should "for 1.0.0-RC1 return true" in {
+    isSbtApiCompatible("1.0.0-RC1") shouldBe true
   }
-  it should "return Scala API for 2.10.0 as Some((2, 10))" in {
-    CrossVersion.scalaApiVersion("2.10.0") shouldBe Some((2, 10))
+  it should "for 1.0.0 return true" in {
+    isSbtApiCompatible("1.0.0") shouldBe true
   }
-  it should "return Scala API for 2.10.0-1 as Some((2, 10))" in {
-    CrossVersion.scalaApiVersion("2.10.0-1") shouldBe Some((2, 10))
+  it should "for 1.0.2-M1 return true" in {
+    isSbtApiCompatible("1.0.2-M1") shouldBe true
   }
-  it should "return Scala API for 2.10.1-SNAPSHOT as Some((2, 10))" in {
-    CrossVersion.scalaApiVersion("2.10.1-SNAPSHOT") shouldBe Some((2, 10))
+  it should "for 1.0.2-RC1 return true" in {
+    isSbtApiCompatible("1.0.2-RC1") shouldBe true
   }
-  it should "return Scala API for 2.10.1-RC1 as Some((2, 10))" in {
-    CrossVersion.scalaApiVersion("2.10.1-RC1") shouldBe Some((2, 10))
+  it should "for 1.0.2 return true" in {
+    isSbtApiCompatible("1.0.2") shouldBe true
   }
-  it should "return Scala API for 2.10.1 as Some((2, 10))" in {
-    CrossVersion.scalaApiVersion("2.10.1") shouldBe Some((2, 10))
+  it should "for 1.3.0 return true" in {
+    isSbtApiCompatible("1.3.0") shouldBe true
   }
-  it should "return Scala API compatibility for 2.10.0-M1 as false" in {
-    CrossVersion.isScalaApiCompatible("2.10.0-M1") shouldBe false
+  it should "for 1.10.0 return true" in {
+    isSbtApiCompatible("1.10.0") shouldBe true
   }
-  it should "return Scala API compatibility for 2.10.0-RC1 as false" in {
-    CrossVersion.isScalaApiCompatible("2.10.0-RC1") shouldBe false
+  it should "for 2.0.0 return true" in {
+    isSbtApiCompatible("2.0.0") shouldBe true
   }
-  it should "return Scala API compatibility for 2.10.1-RC1 as false" in {
-    CrossVersion.isScalaApiCompatible("2.10.1-RC1") shouldBe true
+
+  "binarySbtVersion" should "for 0.11.3 return 0.11.3" in {
+    binarySbtVersion("0.11.3") shouldBe "0.11.3"
   }
-  it should "return binary Scala version for 2.9.2 as 2.9.2" in {
-    CrossVersion.binaryScalaVersion("2.9.2") shouldBe "2.9.2"
+  it should "for 0.12.0-M1 return 0.12.0-M1" in {
+    binarySbtVersion("0.12.0-M1") shouldBe "0.12.0-M1"
   }
-  it should "return binary Scala version for 2.10.0-M1 as 2.10.0-M1" in {
-    CrossVersion.binaryScalaVersion("2.10.0-M1") shouldBe "2.10.0-M1"
+  it should "for 0.12.0-RC1 return 0.12" in {
+    binarySbtVersion("0.12.0-RC1") shouldBe "0.12"
   }
-  it should "return binary Scala version for 2.10.0-RC1 as 2.10.0-RC1" in {
-    CrossVersion.binaryScalaVersion("2.10.0-RC1") shouldBe "2.10.0-RC1"
+  it should "for 0.12.0 return 0.12" in {
+    binarySbtVersion("0.12.0") shouldBe "0.12"
   }
-  it should "return binary Scala version for 2.10.0 as 2.10" in {
-    CrossVersion.binaryScalaVersion("2.10.0") shouldBe "2.10"
+  it should "for 0.12.1-SNAPSHOT return 0.12" in {
+    binarySbtVersion("0.12.1-SNAPSHOT") shouldBe "0.12"
   }
-  it should "return binary Scala version for 2.10.1-M1 as 2.10" in {
-    CrossVersion.binaryScalaVersion("2.10.1-M1") shouldBe "2.10"
+  it should "for 0.12.1-RC1 return 0.12" in {
+    binarySbtVersion("0.12.1-RC1") shouldBe "0.12"
   }
-  it should "return binary Scala version for 2.10.1-RC1 as 2.10" in {
-    CrossVersion.binaryScalaVersion("2.10.1-RC1") shouldBe "2.10"
+  it should "for 0.12.1 return 0.12" in {
+    binarySbtVersion("0.12.1") shouldBe "0.12"
   }
-  it should "return binary Scala version for 2.10.1 as 2.10" in {
-    CrossVersion.binaryScalaVersion("2.10.1") shouldBe "2.10"
+  it should "for 1.0.0-M6 return 1.0.0-M6" in {
+    binarySbtVersion("1.0.0-M6") shouldBe "1.0.0-M6"
   }
-  it should "return binary Scala version for 2.20170314093845.0-87654321 as 2.20170314093845.0-87654321" in {
-    CrossVersion.binaryScalaVersion("2.20170314093845.0-87654321") shouldBe "2.20170314093845.0-87654321"
+  it should "for 1.0.0-RC1 return 1.0" in {
+    binarySbtVersion("1.0.0-RC1") shouldBe "1.0"
   }
-  it should "return binary Scala version for Dotty 0.1.1 as 0.1" in {
-    CrossVersion.binaryScalaVersion("0.1.1") shouldBe "0.1"
+  it should "for 1.0.0 return 1.0" in {
+    binarySbtVersion("1.0.0") shouldBe "1.0"
   }
-  it should "return patch Scala version for 2.11.8 as 2.11.8" in {
-    CrossVersion(CrossVersion.patch, "2.11.8", "dummy").map(_("artefact")) shouldBe Some(
-      "artefact_2.11.8")
+  it should "for 1.0.2-M1 return 1.0" in {
+    binarySbtVersion("1.0.2-M1") shouldBe "1.0"
   }
-  it should "return patch Scala version for 2.11.8-M1 as 2.11.8-M1" in {
-    CrossVersion(CrossVersion.patch, "2.11.8-M1", "dummy").map(_("artefact")) shouldBe Some(
-      "artefact_2.11.8-M1")
+  it should "for 1.0.2-RC1 return 1.0" in {
+    binarySbtVersion("1.0.2-RC1") shouldBe "1.0"
   }
-  it should "return patch Scala version for 2.11.8-RC1 as 2.11.8-RC1" in {
-    CrossVersion(CrossVersion.patch, "2.11.8-RC1", "dummy").map(_("artefact")) shouldBe Some(
-      "artefact_2.11.8-RC1")
+  it should "for 1.0.2 return 1.0" in {
+    binarySbtVersion("1.0.2") shouldBe "1.0"
   }
-  it should "return patch Scala version for 2.11.8-bin-extra as 2.11.8" in {
-    CrossVersion(CrossVersion.patch, "2.11.8-bin-extra", "dummy").map(_("artefact")) shouldBe Some(
-      "artefact_2.11.8")
+  it should "for 1.3.0 return 1.0" in {
+    binarySbtVersion("1.3.0") shouldBe "1.0"
   }
-  it should "return patch Scala version for 2.11.8-M1-bin-extra as 2.11.8-M1" in {
-    CrossVersion(CrossVersion.patch, "2.11.8-M1-bin-extra", "dummy")
-      .map(_("artefact")) shouldBe Some("artefact_2.11.8-M1")
+  it should "for 1.10.0 return 1.0" in {
+    binarySbtVersion("1.10.0") shouldBe "1.0"
   }
-  it should "return patch Scala version for 2.11.8-RC1-bin-extra as 2.11.8-RC1" in {
-    CrossVersion(CrossVersion.patch, "2.11.8-RC1-bin-extra", "dummy")
-      .map(_("artefact")) shouldBe Some("artefact_2.11.8-RC1")
+  it should "for 2.0.0 return 2.0" in {
+    binarySbtVersion("2.0.0") shouldBe "2.0"
   }
-  it should "return disabled cross version as equal to a copy" in {
+
+  "scalaApiVersion" should "for xyz return None" in {
+    scalaApiVersion("xyz") shouldBe None
+  }
+  it should "for 2.10 return None" in {
+    scalaApiVersion("2.10") shouldBe None
+  }
+  it should "for 2.10.0-SNAPSHOT return None" in {
+    scalaApiVersion("2.10.0-SNAPSHOT") shouldBe None
+  }
+  it should "for 2.10.0-RC1 return None" in {
+    scalaApiVersion("2.10.0-RC1") shouldBe None
+  }
+  it should "for 2.10.0 return Some((2, 10))" in {
+    scalaApiVersion("2.10.0") shouldBe Some((2, 10))
+  }
+  it should "for 2.10.0-1 return Some((2, 10))" in {
+    scalaApiVersion("2.10.0-1") shouldBe Some((2, 10))
+  }
+  it should "for 2.10.1-SNAPSHOT return Some((2, 10))" in {
+    scalaApiVersion("2.10.1-SNAPSHOT") shouldBe Some((2, 10))
+  }
+  it should "for 2.10.1-RC1 return Some((2, 10))" in {
+    scalaApiVersion("2.10.1-RC1") shouldBe Some((2, 10))
+  }
+  it should "for 2.10.1 return Some((2, 10))" in {
+    scalaApiVersion("2.10.1") shouldBe Some((2, 10))
+  }
+
+  "isScalaApiCompatible" should "for 2.10.0-M1 return false" in {
+    isScalaApiCompatible("2.10.0-M1") shouldBe false
+  }
+  it should "for 2.10.0-RC1 return false" in {
+    isScalaApiCompatible("2.10.0-RC1") shouldBe false
+  }
+  it should "for 2.10.1-RC1 return false" in {
+    isScalaApiCompatible("2.10.1-RC1") shouldBe true
+  }
+
+  "binaryScalaVersion" should "for 2.9.2 return 2.9.2" in {
+    binaryScalaVersion("2.9.2") shouldBe "2.9.2"
+  }
+  it should "for 2.10.0-M1 return 2.10.0-M1" in {
+    binaryScalaVersion("2.10.0-M1") shouldBe "2.10.0-M1"
+  }
+  it should "for 2.10.0-RC1 return 2.10.0-RC1" in {
+    binaryScalaVersion("2.10.0-RC1") shouldBe "2.10.0-RC1"
+  }
+  it should "for 2.10.0 return 2.10" in {
+    binaryScalaVersion("2.10.0") shouldBe "2.10"
+  }
+  it should "for 2.10.1-M1 return 2.10" in {
+    binaryScalaVersion("2.10.1-M1") shouldBe "2.10"
+  }
+  it should "for 2.10.1-RC1 return 2.10" in {
+    binaryScalaVersion("2.10.1-RC1") shouldBe "2.10"
+  }
+  it should "for 2.10.1 return 2.10" in {
+    binaryScalaVersion("2.10.1") shouldBe "2.10"
+  }
+  it should "for 2.20170314093845.0-87654321 return 2.20170314093845" in {
+    binaryScalaVersion("2.20170314093845.0-87654321") shouldBe "2.20170314093845"
+  }
+  it should "for Dotty 0.1.1 return 0.1" in {
+    binaryScalaVersion("0.1.1") shouldBe "0.1"
+  }
+
+  private def patchVersion(fullVersion: String) =
+    CrossVersion(CrossVersion.patch, fullVersion, "dummy") map (fn => fn("artefact"))
+
+  "CrossVersion.patch" should "for 2.11.8 return 2.11.8" in {
+    patchVersion("2.11.8") shouldBe Some("artefact_2.11.8")
+  }
+  it should "for 2.11.8-M1 return 2.11.8-M1" in {
+    patchVersion("2.11.8-M1") shouldBe Some("artefact_2.11.8-M1")
+  }
+  it should "for 2.11.8-RC1 return 2.11.8-RC1" in {
+    patchVersion("2.11.8-RC1") shouldBe Some("artefact_2.11.8-RC1")
+  }
+  it should "for 2.11.8-bin-extra return 2.11.8" in {
+    patchVersion("2.11.8-bin-extra") shouldBe Some("artefact_2.11.8")
+  }
+  it should "for 2.11.8-M1-bin-extra return 2.11.8-M1" in {
+    patchVersion("2.11.8-M1-bin-extra") shouldBe Some("artefact_2.11.8-M1")
+  }
+  it should "for 2.11.8-RC1-bin-extra return 2.11.8-RC1" in {
+    patchVersion("2.11.8-RC1-bin-extra") shouldBe Some("artefact_2.11.8-RC1")
+  }
+
+  "Disabled" should "have structural equality" in {
     Disabled() shouldBe Disabled()
   }
-  it should "return full cross version as equal to a copy" in {
+  "CrossVersion.full" should "have structural equality" in {
     CrossVersion.full shouldBe CrossVersion.full
   }
-  it should "return binary cross version as equal to a copy" in {
+  "CrossVersion.binary" should "have structural equality" in {
     CrossVersion.binary shouldBe CrossVersion.binary
   }
 }