coursier-versions is the library parsing and comparing versions of coursier.

It's mainly designed around the needs of coursier itself, but can find uses outside of it.

It aims at not breaking backward binary compatibility, and follows semantic versioning. While still in 0.x, backward binary compatibility hasn't been broken since its first release.


Add to your build.sbt:

libraryDependencies += "io.get-coursier" %% "versions" % "0.2.1"

The latest version is Maven Central.

All coursier-versions classes live under the coursier.version namespace. The snippets below assume

import coursier.version._


Version parsing and comparison is handled by coursier.version.Version.

Parse a version with

val version = Version("1.2.0-RC3")
// version: Version = Version("1.2.0-RC3")
val items = version.items
// items: Vector[Version.Item] = Vector(
//   Number(1),
//   Number(2),
//   Number(0),
//   Tag("rc"),
//   Number(3)
// )

Parsing is meant to be very loose, and tries to make sense of any input. The actual parsing happens when items, which is a lazy val, is called on Version.

If you'd like to reject potentially invalid inputs, use VersionParse.version:

val versionOpt = VersionParse.version("[1.2,1.3)")
// versionOpt: Option[Version] = None

The parsing logic is originally based on Maven / Aether version parsing, which was later tweaked to accommodate Scala / sbt needs.

items gives the list of elements composing the parsed version, and is later used to compare versions.

The coursier documentation details how versions are compared.

Version implements Ordered[Version], so that Version instances can be compared together, and a sequence of Versions can be sorted.


VersionConstraint aims at representing not only versions, but also version intervals, or interval selectors such as 1.2+.

Parse a version constraint with

val intervalConstraint = VersionParse.versionConstraint("[1.2,1.3)")
// intervalConstraint: VersionConstraint = VersionConstraint(
//   VersionInterval(Some(Version("1.2")), Some(Version("1.3")), true, false),
//   List()
// )
val intervalSelectorConstraint = VersionParse.versionConstraint("1.2+")
// intervalSelectorConstraint: VersionConstraint = VersionConstraint(
//   VersionInterval(Some(Version("1.2")), Some(Version("1.2.max")), true, true),
//   List()
// )
val simpleVersionConstraint = VersionParse.versionConstraint("1.4.2")
// simpleVersionConstraint: VersionConstraint = VersionConstraint(
//   VersionInterval(None, None, false, false),
//   List(Version("1.4.2"))
// )

Like for versions, parsing is meant to be very loose, trying to make sense of any input.


ModuleMatcher aims at representing glob-based module matchers, like

val matcher = ModuleMatcher("org.scala-lang.modules", "*")
// matcher: ModuleMatcher = ModuleMatcher("org.scala-lang.modules", "*", Map())
val matchesScalaXml = matcher.matches("org.scala-lang.modules", "scala-xml_2.13")
// matchesScalaXml: Boolean = true
val matchesCoursier = matcher.matches("io.get-coursier", "coursier_2.13")
// matchesCoursier: Boolean = false


Slightly more powerful than ModuleMatcher, ModuleMatchers can either include or exclude all modules by default, and both include or exclude modules from glob-based expressions, like

val allButScalaLib = ModuleMatchers(
  exclude = Set(ModuleMatcher("org.scala-lang", "scala-library")),
  include = Set(),
  includeByDefault = true
// allButScalaLib: ModuleMatchers = ModuleMatchers(
//   Set(ModuleMatcher("org.scala-lang", "scala-library", Map())),
//   Set(),
//   true
// )
val notScalaLib = allButScalaLib.matches("io.get-coursier", "coursier_2.13")
// notScalaLib: Boolean = true
val scalaLib = allButScalaLib.matches("org.scala-lang", "scala-library")
// scalaLib: Boolean = false


VersionCompatibility checks whether two versions, or a version constraint and a version, are compatible with each other.

The following algorithms are available:

  • EarlySemVer: early semantic versioning that keeps 0.6.z bincompat
  • SemVerSpec: semantic versioning spec that treats all 0.y.z as initial development
  • PackVer: package versioning policy
  • Strict: exact match required
  • Always: assume any input constraint and version match
  • Default: currently equal to PackVer
val semVerCheck1 = VersionCompatibility.EarlySemVer.isCompatible("1.2.0", "1.2.4")
// semVerCheck1: Boolean = true
val semVerCheck2 = VersionCompatibility.EarlySemVer.isCompatible("1.2+", "1.2.4")
// semVerCheck2: Boolean = true
val semVerCheck3 = VersionCompatibility.EarlySemVer.isCompatible("2.1.3", "1.2.4")
// semVerCheck3: Boolean = false
val strictCheck1 = VersionCompatibility.Strict.isCompatible("1.2.0", "1.2.4")
// strictCheck1: Boolean = false
val strictCheck2 = VersionCompatibility.Strict.isCompatible("1.2+", "1.2.4")
// strictCheck2: Boolean = true
val strictCheck3 = VersionCompatibility.Strict.isCompatible("2.1.3", "1.2.4")
// strictCheck3: Boolean = false