build.sbt

val scala211 = "2.11.12" // up to 2.11.12
val scala212 = "2.12.19" // up to 2.12.19
val scala213 = "2.13.14" // up to 2.13.14
val scala30  = "3.0.2"   // up to 3.0.2
val scala31  = "3.1.3"   // up to 3.1.3
val scala32  = "3.2.2"   // up to 3.2.2
val scala33  = "3.3.3"   // up to 3.3.3
val scala34  = "3.4.2"   // up to 3.4.2

val scala3   = scala31

// See https://www.scala-lang.org/blog/2022/08/17/long-term-compatibility-plans.html.
// Scala30: "If you are maintaining a library, you should drop Scala 3.0."  Dropped.
// Scala31: This is a LTS (long term support) version before it was called that.
// Scala32: This is for experimentation, as in Scala Next, and not for release.
// Scala33: This is the first official LTS, but hold off until necessary.
ThisBuild / crossScalaVersions := Seq(scala212, scala211, scala213, scala3)
ThisBuild / scalaVersion := crossScalaVersions.value.head

lazy val root = (project in file("."))
  // Skip webapp because it only works for particular Scala versions.
  // It needs to be released separately (if at all).
  .aggregate(library, apps)
  .settings(
    publish / skip := true
  )

lazy val library = project

lazy val apps = project
  .dependsOn(library % "compile -> compile; test -> test")

lazy val webapp = project
  .enablePlugins(PlayScala)
  .dependsOn(library % "compile -> compile; test -> test")
  .settings(
    // scala3 doesn't have play (for 2.8.19 as specified by the project) and is ruled out completely.
    // scala213 has version problems for com.fasterxml.jackson.databind.JsonMappingException.
    // scala212 works!
    // scala211 isn't compiling and complains on twirlCompileTemplates.
    // This isn't a library.  Only one version needs to work.  We shouldn't use play for this anyway.
    crossScalaVersions := Seq(scala212)
  )

addCommandAlias("dockerizeWebapp", ";webapp/docker:publishLocal")