Upgrade scala version to 2.12.12

This introduces `Def.unit(...)` to workaround the pure expression does nothing warning.

.travis.yml

@@ -5,7 +5,7 @@ language: scala
 env:
   global:
     - TRAVIS_JDK=adopt@1.11.0-1
-    - SCALA_212=2.12.11
+    - SCALA_212=2.12.12
     - SCALA_213=2.13.1
     - UTIL_TESTS="utilCache/test;utilControl/test;utilInterface/test;utilLogging/test;utilPosition/test;utilRelation/test;utilScripted/test;utilTracking/test"
     # WHITESOURCE_PASSWORD=

main-settings/src/main/scala/sbt/Def.scala

@@ -320,6 +320,16 @@ object Def extends Init[Scope] with TaskMacroExtra with InitializeImplicits {
     def toTaskable: Taskable[T] = x
   }
 
+  /** This works around Scala 2.12.12's
+   * "a pure expression does nothing in statement position"
+   *
+   * {{{
+   * Def.unit(copyResources.value)
+   * Def.unit(compile.value)
+   * }}}
+   */
+  def unit(a: Any): Unit = ()
+
   private[sbt] def dummy[T: Manifest](name: String, description: String): (TaskKey[T], Task[T]) =
     (TaskKey[T](name, description, DTask), dummyTask(name))
 

main-settings/src/test/scala/sbt/std/TaskPosSpec.scala

@@ -164,7 +164,7 @@ class TaskPosSpec {
     def withKey(foo: => SettingKey[String]): Def.Initialize[Task[Unit]] = {
       Def.task {
         if (true) {
-          foo.value; ()
+          Def.unit(foo.value); ()
         }
       }
     }

main/src/main/scala/sbt/Defaults.scala

@@ -2007,7 +2007,7 @@ object Defaults extends BuildCommon {
   private[sbt] def compileJavaTask: Initialize[Task[CompileResult]] = Def.task {
     val s = streams.value
     val in = (compileJava / compileInputs).value
-    val _ = compileScalaBackend.value
+    Def.unit(compileScalaBackend.value)
     try {
       incCompiler.asInstanceOf[sbt.internal.inc.IncrementalCompilerImpl].compileAllJava(in, s.log)
     } finally {
@@ -3162,7 +3162,7 @@ object Classpaths {
 
   def deliverTask(config: TaskKey[PublishConfiguration]): Initialize[Task[File]] =
     Def.task {
-      val _ = update.value
+      Def.unit(update.value)
       IvyActions.deliver(ivyModule.value, config.value, streams.value.log)
     }
 
@@ -3492,8 +3492,9 @@ object Classpaths {
   def analyzed[T](data: T, analysis: CompileAnalysis) = ClasspathImpl.analyzed[T](data, analysis)
   def makeProducts: Initialize[Task[Seq[File]]] = Def.task {
     val c = fileConverter.value
-    compile.value
-    copyResources.value
+    Def.unit(copyResources.value)
+    Def.unit(compile.value)
+
     c.toPath(backendOutput.value).toFile :: Nil
   }
 

main/src/main/scala/sbt/PluginCross.scala

@@ -96,7 +96,7 @@ private[sbt] object PluginCross {
     VersionNumber(sv) match {
       case VersionNumber(Seq(0, 12, _*), _, _) => "2.9.2"
       case VersionNumber(Seq(0, 13, _*), _, _) => "2.10.7"
-      case VersionNumber(Seq(1, 0, _*), _, _)  => "2.12.11"
+      case VersionNumber(Seq(1, 0, _*), _, _)  => "2.12.12"
       case _                                   => sys.error(s"Unsupported sbt binary version: $sv")
     }
 }

main/src/main/scala/sbt/ScriptedPlugin.scala

@@ -178,7 +178,7 @@ object ScriptedPlugin extends AutoPlugin {
 
   private[sbt] def scriptedTask: Initialize[InputTask[Unit]] = Def.inputTask {
     val args = scriptedParser(sbtTestDirectory.value).parsed
-    scriptedDependencies.value
+    Def.unit(scriptedDependencies.value)
     try {
       val method = scriptedRun.value
       val scriptedInstance = scriptedTests.value

main/src/main/scala/sbt/internal/TaskSequential.scala

@@ -771,13 +771,13 @@ trait TaskSequential {
       case Nil => Def.task { last.value }
       case x :: xs =>
         Def.taskDyn {
-          val _ = x.value
+          Def.unit(x.value)
           sequential(xs, last)
         }
     }
   private def unitTask[A](task: Initialize[Task[A]]): Initialize[Task[Unit]] =
     Def.task {
-      task.value
+      Def.unit(task.value)
       ()
     }
 }

main/src/main/scala/sbt/nio/Settings.scala

@@ -256,7 +256,7 @@ private[sbt] object Settings {
     addTaskDefinition(sbt.Keys.clean in taskScope := Def.taskDyn {
       // the clean file task needs to run first because the previous cache gets blown away
       // by the second task
-      Clean.cleanFileOutputTask(taskKey).value
+      Def.unit(Clean.cleanFileOutputTask(taskKey).value)
       Clean.task(taskScope, full = false)
     }.value)
   }

project/Dependencies.scala

@@ -4,8 +4,8 @@ import sbt.contraband.ContrabandPlugin.autoImport._
 
 object Dependencies {
   // WARNING: Please Scala update versions in PluginCross.scala too
-  val scala212 = "2.12.11"
-  val scala213 = "2.13.1"
+  val scala212 = "2.12.12"
+  val scala213 = "2.13.3"
   val checkPluginCross = settingKey[Unit]("Make sure scalaVersion match up")
   val baseScalaVersion = scala212
   def nightlyVersion = sys.props.get("sbt.build.version")

sbt/src/sbt-test/actions/cross-advanced/build.sbt

@@ -10,19 +10,19 @@ lazy val root = (project in file("."))
 
 lazy val foo = project
   .settings(
-    crossScalaVersions := Seq("2.12.11", "2.13.1"),
+    crossScalaVersions := Seq("2.12.12", "2.13.1"),
     libraryDependencies += "org.scalatest" %% "scalatest" % "3.1.0",
 
     check := {
       // This tests that +check will respect bar's crossScalaVersions and not switch
       val x = (LocalProject("bar") / scalaVersion).value
-      assert(x == "2.12.11", s"$x == 2.12.11")
+      assert(x == "2.12.12", s"$x == 2.12.12")
       (Compile / compile).value
     },
     (Test / testOnly) := {
       // This tests that +testOnly will respect bar's crossScalaVersions and not switch
       val x = (LocalProject("bar") / scalaVersion).value
-      assert(x == "2.12.11", s"$x == 2.12.11")
+      assert(x == "2.12.12", s"$x == 2.12.12")
       val _ = (Test / testOnly).evaluated
     },
     compile2 := {
@@ -35,7 +35,7 @@ lazy val foo = project
 
 lazy val bar = project
   .settings(
-    crossScalaVersions := Seq("2.12.11"),
+    crossScalaVersions := Seq("2.12.12"),
     check := (Compile / compile).value,
     compile2 := (Compile / compile).value,
   )
@@ -46,14 +46,14 @@ lazy val baz = project
     check := {
       // This tests that +baz/check will respect bar's crossScalaVersions and not switch
       val x = (LocalProject("bar") / scalaVersion).value
-      assert(x == "2.12.11", s"$x == 2.12.11")
+      assert(x == "2.12.12", s"$x == 2.12.12")
       (Compile / compile).value
     },
   )
 
 lazy val client = project
   .settings(
-    crossScalaVersions := Seq("2.12.11", "2.13.1"),
+    crossScalaVersions := Seq("2.12.12", "2.13.1"),
     check := (Compile / compile).value,
     compile2 := (Compile / compile).value,
   )

sbt/src/sbt-test/actions/cross-advanced/test

@@ -17,7 +17,7 @@
 ## test + with command or alias
 > clean
 ## for command cross building you do need crossScalaVerions on root
-> set root/crossScalaVersions := Seq("2.12.11", "2.13.1")
+> set root/crossScalaVersions := Seq("2.12.12", "2.13.1")
 > + build
 $ exists foo/target/scala-2.12
 $ exists foo/target/scala-2.13

sbt/src/sbt-test/actions/cross-incremental/build.sbt

@@ -1,5 +1,5 @@
-scalaVersion := "2.12.11"
-crossScalaVersions := List("2.12.11", "2.13.0")
+scalaVersion := "2.12.12"
+crossScalaVersions := List("2.12.12", "2.13.0")
 
 val setLastModified = taskKey[Unit]("Sets the last modified time for classfiles")
 setLastModified := {

sbt/src/sbt-test/actions/cross-multi-parser/build.sbt

@@ -1 +1 @@
-crossScalaVersions := Seq[String]("2.11.12", "2.12.11")
+crossScalaVersions := Seq[String]("2.11.12", "2.12.12")

sbt/src/sbt-test/actions/cross-multi-parser/test

@@ -1,5 +1,5 @@
 > ++2.11.12; compile
 
-> ++ 2.12.11  ; compile;
+> ++ 2.12.12  ; compile;
 
-> ++ 2.12.11 ; compile
+> ++ 2.12.12 ; compile

sbt/src/sbt-test/actions/cross-multiproject/build.sbt

@@ -1,4 +1,4 @@
-lazy val scala212 = "2.12.11"
+lazy val scala212 = "2.12.12"
 // keep this at M5 to test full version
 lazy val scala213 = "2.13.1"
 

sbt/src/sbt-test/actions/cross-multiproject/test

@@ -13,7 +13,7 @@ $ exists lib/target/scala-2.13
 
 # test safe switching
 > clean
-> ++ 2.12.11 -v compile
+> ++ 2.12.12 -v compile
 $ exists lib/target/scala-2.12
 -$ exists lib/target/scala-2.13
 $ exists sbt-foo/target/scala-2.12
@@ -29,7 +29,7 @@ $ exists sbt-foo/target/scala-2.12
 
 # Test ++ leaves crossScalaVersions unchanged
 > clean
-> ++2.12.11
+> ++2.12.12
 > +extrasProj/compile
 $ exists extras/target/scala-2.13
 $ exists extras/target/scala-2.12

sbt/src/sbt-test/actions/cross-strict-aggregation/build.sbt

@@ -1,4 +1,4 @@
-lazy val scala212 = "2.12.11"
+lazy val scala212 = "2.12.12"
 lazy val scala213 = "2.13.1"
 
 ThisBuild / scalaVersion := scala212

sbt/src/sbt-test/actions/cross/build.sbt

@@ -2,11 +2,11 @@ ThisBuild / scalaVersion := "2.11.12"
 
 lazy val root = (project in file("."))
   .settings(
-    scalaVersion := "2.12.11",
+    scalaVersion := "2.12.12",
 
     update / scalaVersion := {
       scalaVersion.value match {
-        case "2.12.11" => "2.12.10"
+        case "2.12.12" => "2.12.10"
         case "2.11.12" => "2.11.11"
         case x         => x
       }

sbt/src/sbt-test/actions/cross/test

@@ -1,4 +1,4 @@
-> check 2.11.12 2.12.11 2.12.10
+> check 2.11.12 2.12.12 2.12.10
 
 > ++ 2.11.12!
 > check 2.11.12 2.11.12 2.11.11
@@ -8,4 +8,4 @@
 > check 2.13.1 2.13.1 2.13.1
 
 > session clear-all
-> check 2.11.12 2.12.11 2.12.10
+> check 2.11.12 2.12.12 2.12.10

sbt/src/sbt-test/actions/doc-file-options/build.sbt

@@ -2,7 +2,7 @@ val newContents = "bbbbbbbbb"
 
 val rootContentFile = "root.txt"
 
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 lazy val root = (project in file("."))
   .settings(

sbt/src/sbt-test/actions/generator/build.sbt

@@ -1,6 +1,6 @@
 val buildInfo = taskKey[Seq[File]]("generates the build info")
 
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 lazy val root = (project in file("."))
   .settings(

sbt/src/sbt-test/actions/multi-command/build.sbt

@@ -19,4 +19,4 @@ val dynamicTask = taskKey[Unit]("dynamic input task")
 
 dynamicTask := { println("not yet et") }
 
-crossScalaVersions := "2.11.12" :: "2.12.11" :: Nil
+crossScalaVersions := "2.11.12" :: "2.12.12" :: Nil

sbt/src/sbt-test/actions/multi-command/test

@@ -37,4 +37,4 @@
 
 > ++ 2.11.12 compile; setStringValue bar; checkStringValue bar
 
-> ++2.12.11 compile; setStringValue foo; checkStringValue foo
+> ++2.12.12 compile; setStringValue foo; checkStringValue foo

sbt/src/sbt-test/actions/remote-cache/build.sbt

@@ -4,7 +4,7 @@ lazy val root = (project in file("."))
   .configs(CustomArtifact)
   .settings(
     name := "my-project",
-    scalaVersion := "2.12.11",
+    scalaVersion := "2.12.12",
     pushRemoteCacheTo := Some(
       MavenCache("local-cache", (ThisBuild / baseDirectory).value / "remote-cache")
     ),

sbt/src/sbt-test/classloader-cache/akka-actor-system/build.sbt

@@ -2,7 +2,7 @@ ThisBuild / turbo := true
 
 val akkaTest = (project in file(".")).settings(
   name := "akka-test",
-  scalaVersion := "2.12.11",
+  scalaVersion := "2.12.12",
   libraryDependencies ++= Seq(
     "com.typesafe.akka" %% "akka-actor" % "2.5.16",
     "com.lihaoyi" %% "utest" % "0.6.6" % "test"

sbt/src/sbt-test/classloader-cache/jni/build.sbt

@@ -13,7 +13,7 @@ def wrap(task: InputKey[Unit]): Def.Initialize[Task[Unit]] =
 ThisBuild / turbo := true
 
 val root = (project in file(".")).settings(
-  scalaVersion := "2.12.11",
+  scalaVersion := "2.12.12",
   javacOptions ++= Seq("-source", "1.8", "-target", "1.8", "-h",
   sourceDirectory.value.toPath.resolve("main/native/include").toString),
   libraryDependencies += "com.lihaoyi" %% "utest" % "0.6.6" % "test",

sbt/src/sbt-test/classloader-cache/library-mismatch/build.sbt

@@ -2,7 +2,7 @@ ThisBuild / turbo := true
 
 val snapshot = (project in file(".")).settings(
   name := "mismatched-libraries",
-  scalaVersion := "2.12.11",
+  scalaVersion := "2.12.12",
   libraryDependencies ++= Seq("com.lihaoyi" %% "utest" % "0.6.6" % "test"),
   testFrameworks := Seq(TestFramework("utest.runner.Framework")),
   resolvers += "Local Maven" at file("libraries/ivy").toURI.toURL.toString,

sbt/src/sbt-test/classloader-cache/runtime-layers/build.sbt

@@ -1,6 +1,6 @@
 val layeringStrategyTest = (project in file(".")).settings(
   name := "layering-strategy-test",
-  scalaVersion := "2.12.11",
+  scalaVersion := "2.12.12",
   organization := "sbt",
   libraryDependencies += "com.typesafe.akka" %% "akka-actor" % "2.5.16",
 )

sbt/src/sbt-test/classloader-cache/snapshot/build.sbt

@@ -9,7 +9,7 @@ ThisBuild / useCoursier := false
 
 val snapshot = (project in file(".")).settings(
   name := "akka-test",
-  scalaVersion := "2.12.11",
+  scalaVersion := "2.12.12",
   libraryDependencies ++= Seq(
     "com.lihaoyi" %% "utest" % "0.6.6" % "test"
   ),

sbt/src/sbt-test/classloader-cache/snapshot/libraries/library-1/ivy/sbt/foo-lib_2.12/0.1.0-SNAPSHOT/foo-lib_2.12-0.1.0-SNAPSHOT.pom

@@ -14,7 +14,7 @@
         <dependency>
             <groupId>org.scala-lang</groupId>
             <artifactId>scala-library</artifactId>
-            <version>2.12.11</version>
+            <version>2.12.12</version>
         </dependency>
     </dependencies>
 </project>

sbt/src/sbt-test/classloader-cache/snapshot/libraries/library-2/ivy/sbt/foo-lib_2.12/0.1.0-SNAPSHOT/foo-lib_2.12-0.1.0-SNAPSHOT.pom

@@ -14,7 +14,7 @@
         <dependency>
             <groupId>org.scala-lang</groupId>
             <artifactId>scala-library</artifactId>
-            <version>2.12.11</version>
+            <version>2.12.12</version>
         </dependency>
     </dependencies>
 </project>

sbt/src/sbt-test/classloader-cache/spark/build.sbt

@@ -2,7 +2,7 @@ name := "Simple Project"
 
 version := "1.0"
 
-scalaVersion := "2.12.11"
+scalaVersion := "2.12.12"
 
 libraryDependencies += "org.apache.spark" %% "spark-sql" % "2.4.3"
 

sbt/src/sbt-test/classloader-cache/utest/build.sbt

@@ -2,7 +2,7 @@ ThisBuild / turbo := true
 
 val utestTest = (project in file(".")).settings(
   name := "utest-test",
-  scalaVersion := "2.12.11",
+  scalaVersion := "2.12.12",
   libraryDependencies ++= Seq(
     "com.lihaoyi" %% "utest" % "0.6.6" % "test"
   ),

sbt/src/sbt-test/compiler-project/error-in-invalidated/build.sbt

@@ -1,4 +1,4 @@
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 lazy val root = (project in file(".")).
   settings(

sbt/src/sbt-test/compiler-project/separate-analysis-per-scala/build.sbt

@@ -1,4 +1,4 @@
-lazy val scala212 = "2.12.11"
+lazy val scala212 = "2.12.12"
 lazy val scala213 = "2.13.1"
 ThisBuild / scalaVersion := scala212
 

sbt/src/sbt-test/console/project-compiler-bridge/project/build.sbt

@@ -1 +1 @@
-scalaVersion := "2.12.11"
+scalaVersion := "2.12.12"

sbt/src/sbt-test/dependency-management/artifact/build.sbt

@@ -5,7 +5,7 @@ lazy val check = taskKey[Unit]("")
 lazy val checkArtifact = taskKey[Unit]("")
 
 ThisBuild / useCoursier := false
-ThisBuild / scalaVersion     := "2.12.11"
+ThisBuild / scalaVersion     := "2.12.12"
 ThisBuild / version          := "0.1.0-SNAPSHOT"
 ThisBuild / organization     := "com.example"
 ThisBuild / organizationName := "example"

sbt/src/sbt-test/dependency-management/cache-classifiers/multi.sbt

@@ -1,4 +1,4 @@
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 // TTL of Coursier is 24h
 ThisBuild / useCoursier := false

sbt/src/sbt-test/dependency-management/cached-resolution-interproj/multi.sbt

@@ -3,7 +3,7 @@ lazy val check = taskKey[Unit]("Runs the check")
 val scalatest = "org.scalatest" %% "scalatest" % "3.0.5"
 val junit = "junit" % "junit" % "4.11"
 
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 ThisBuild / csrCacheDirectory := (ThisBuild / baseDirectory).value / "coursier-cache"
 
 def commonSettings: Seq[Def.Setting[_]] =

sbt/src/sbt-test/dependency-management/compiler-bridge-binary/build.sbt

@@ -1,4 +1,4 @@
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 lazy val check = taskKey[Unit]("")
 

sbt/src/sbt-test/dependency-management/conflict-coursier/build.sbt

@@ -1,4 +1,4 @@
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 libraryDependencies ++= List(
   "org.webjars.npm" % "randomatic" % "1.1.7",
   "org.webjars.npm" % "is-odd"     % "2.0.0",

sbt/src/sbt-test/dependency-management/evicted-semver-spec/build.sbt

@@ -1,6 +1,6 @@
 // ThisBuild / useCoursier := false
 ThisBuild / organization := "com.example"
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 ThisBuild / versionScheme := Some("semver-spec")
 ThisBuild / csrCacheDirectory := (ThisBuild / baseDirectory).value / "coursier-cache"
 

sbt/src/sbt-test/dependency-management/global-plugins/build.sbt

@@ -1 +1 @@
-scalaVersion := "2.12.11"
+scalaVersion := "2.12.12"

sbt/src/sbt-test/dependency-management/snapshot-local/build.sbt

@@ -1,5 +1,5 @@
 ThisBuild / organization := "com.example"
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 ThisBuild / csrCacheDirectory := (ThisBuild / baseDirectory).value / "coursier-cache"
 
 def customIvyPaths: Seq[Def.Setting[_]] = Seq(

sbt/src/sbt-test/dependency-management/snapshot-resolution/build.sbt

@@ -1,5 +1,5 @@
 ThisBuild / organization := "com.example"
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 // TTL is 24h so we can't detect the change
 ThisBuild / useCoursier := false

sbt/src/sbt-test/dependency-management/sources/build.sbt

@@ -1,4 +1,4 @@
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 lazy val root = (project in file("."))
   .settings(
@@ -14,14 +14,14 @@ def checkSources(report: UpdateReport): Unit = {
     sys.error(s"No sources retrieved\n\n$report")
   else if (srcs.size != 9 || !srcs.exists(_ == "akka-actor_2.12-2.5.22-sources.jar")) {
 // [info] [error] 	scala-java8-compat_2.12-0.8.0-sources.jar
-// [info] [error] 	scala-library-2.12.11-sources.jar
+// [info] [error] 	scala-library-2.12.12-sources.jar
 // [info] [error] 	config-1.3.3-sources.jar
 // [info] [error] 	akka-actor_2.12-2.5.22-sources.jar
-// [info] [error] 	scala-compiler-2.12.11-sources.jar
+// [info] [error] 	scala-compiler-2.12.12-sources.jar
 // [info] [error] 	jline-2.14.6-sources.jar
 // [info] [error] 	jansi-1.12-sources.jar
 // [info] [error] 	scala-xml_2.12-1.0.6-sources.jar
-// [info] [error] 	scala-reflect-2.12.11-sources.jar
+// [info] [error] 	scala-reflect-2.12.12-sources.jar
     sys.error("Incorrect sources retrieved:\n\t" + srcs.mkString("\n\t"))
   } else ()
 }

sbt/src/sbt-test/plugins/hydra/build.sbt

@@ -1,4 +1,4 @@
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 lazy val check = taskKey[Unit]("")
 

sbt/src/sbt-test/plugins/sbt-native-packager/build.sbt

@@ -1,4 +1,4 @@
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 name := "hello"
 enablePlugins(JavaAppPackaging)

sbt/src/sbt-test/project/aggregate/projA/build.sbt

@@ -1,3 +1,3 @@
 name := "projA"
 
-scalaVersion := "2.12.11"
+scalaVersion := "2.12.12"

sbt/src/sbt-test/project/cross-plugins-defaults/build.sbt

@@ -1,7 +1,7 @@
 val baseSbt = "1."
 
-val buildCrossList = List("2.10.7", "2.11.12", "2.12.11")
-scalaVersion in ThisBuild := "2.12.11"
+val buildCrossList = List("2.10.7", "2.11.12", "2.12.12")
+scalaVersion in ThisBuild := "2.12.12"
 crossScalaVersions in ThisBuild := buildCrossList
 
 addSbtPlugin("com.eed3si9n" % "sbt-buildinfo" % "0.7.0")

sbt/src/sbt-test/project/flatten/build.sbt

@@ -1,6 +1,6 @@
 val unpackage = TaskKey[Unit]("unpackage")
 
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 lazy val root = (project in file("."))
   .settings(

sbt/src/sbt-test/project/internal-tracking/build.sbt

@@ -1,4 +1,4 @@
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 ThisBuild / trackInternalDependencies := TrackLevel.NoTracking
 
 lazy val root = (project in file("."))

sbt/src/sbt-test/project/semanticdb/build.sbt

@@ -1,4 +1,4 @@
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 ThisBuild / semanticdbEnabled := true
 ThisBuild / semanticdbIncludeInJar := true
 

sbt/src/sbt-test/run/fork-loader/build.sbt

@@ -1,6 +1,6 @@
 val scalcheck = "org.scalacheck" %% "scalacheck" % "1.14.0"
 
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 lazy val root = (project in file("."))
   .settings(

sbt/src/sbt-test/source-dependencies/binary/build.sbt

@@ -1,4 +1,4 @@
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 lazy val dep = project
 

sbt/src/sbt-test/source-dependencies/cross-source/test

@@ -1,3 +1,3 @@
 # A.scala needs B.scala, it would be in source list
-> ++2.12.11!
+> ++2.12.12!
 > compile

sbt/src/sbt-test/source-dependencies/macro-annotation/build.sbt

@@ -1,4 +1,4 @@
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 val paradiseVersion = "2.1.1"
 val commonSettings = Seq(

sbt/src/sbt-test/source-dependencies/macro-arg-dep-nested/build.sbt

@@ -1,4 +1,4 @@
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 val defaultSettings = Seq(
   libraryDependencies += scalaVersion("org.scala-lang" % "scala-reflect" % _ ).value

sbt/src/sbt-test/source-dependencies/macro-arg-dep-stackoverflow/build.sbt

@@ -1,4 +1,4 @@
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 val defaultSettings = Seq(
   libraryDependencies += scalaVersion("org.scala-lang" % "scala-reflect" % _ ).value

sbt/src/sbt-test/source-dependencies/macro-arg-dep/build.sbt

@@ -1,4 +1,4 @@
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 val defaultSettings = Seq(
   libraryDependencies += scalaVersion("org.scala-lang" % "scala-reflect" % _ ).value

sbt/src/sbt-test/source-dependencies/macro/build.sbt

@@ -1,4 +1,4 @@
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 val defaultSettings = Seq(
   libraryDependencies += scalaVersion("org.scala-lang" % "scala-reflect" % _ ).value

sbt/src/sbt-test/tests/arguments/build.sbt

@@ -1,6 +1,6 @@
 val scalatest = "org.scalatest" %% "scalatest" % "3.0.5"
 
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 val foo = settingKey[Seq[String]]("foo")
 val checkFoo = inputKey[Unit]("check contents of foo")

sbt/src/sbt-test/tests/do-not-discover/build.sbt

@@ -1,6 +1,6 @@
 val scalatest = "org.scalatest" %% "scalatest" % "3.0.5"
 
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 lazy val root = (project in file("."))
   .settings(

sbt/src/sbt-test/tests/done/build.sbt

@@ -1,6 +1,6 @@
 val scalatest = "org.scalatest" %% "scalatest" % "3.0.5"
 
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 lazy val root = (project in file("."))
   .settings(

sbt/src/sbt-test/tests/fork-async/build.sbt

@@ -1,4 +1,4 @@
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 lazy val root = (project in file("."))
   .settings(

sbt/src/sbt-test/tests/fork-parallel/build.sbt

@@ -1,7 +1,7 @@
 import Tests._
 import Defaults._
 
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 val check = taskKey[Unit]("Check that tests are executed in parallel")
 
 lazy val root = (project in file("."))

sbt/src/sbt-test/tests/fork-test-group-parallel-custom-tags/build.sbt

@@ -1,5 +1,5 @@
 val specs = "org.specs2" %% "specs2-core" % "4.3.4"
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 val TestATypeTag = Tags.Tag("TestA")
 val TestBTypeTag = Tags.Tag("TestB")

sbt/src/sbt-test/tests/fork-test-group-parallel/build.sbt

@@ -1,5 +1,5 @@
 val specs = "org.specs2" %% "specs2-core" % "4.3.4"
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 Global / concurrentRestrictions := Seq(Tags.limitAll(4))
 libraryDependencies += specs % Test

sbt/src/sbt-test/tests/fork-uncaught2/build.sbt

@@ -1,4 +1,4 @@
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 libraryDependencies += "org.scala-sbt" % "test-interface" % "1.0"
 

sbt/src/sbt-test/tests/fork/build.sbt

@@ -11,7 +11,7 @@ val scalaxml = "org.scala-lang.modules" %% "scala-xml" % "1.1.1"
 def groupId(idx: Int) = "group_" + (idx + 1)
 def groupPrefix(idx: Int) = groupId(idx) + "_file_"
 
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 ThisBuild / organization := "org.example"
 
 lazy val root = (project in file("."))

sbt/src/sbt-test/tests/fork2/build.sbt

@@ -1,6 +1,6 @@
 val scalatest = "org.scalatest" %% "scalatest" % "3.0.5"
 
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 fork := true
 libraryDependencies += scalatest % Test

sbt/src/sbt-test/tests/it/build.sbt

@@ -1,4 +1,4 @@
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 val specs = "org.specs2" %% "specs2-core" % "4.3.4"
 

sbt/src/sbt-test/tests/junit-xml-report/build.sbt

@@ -14,7 +14,7 @@ val nestedSuitesReportFile = "target/test-reports/TEST-my.scalatest.MyNestedSuit
 val scalatest = "org.scalatest" %% "scalatest" % "3.0.5"
 val junitinterface = "com.novocode" % "junit-interface" % "0.11"
 
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 lazy val root = (project in file(".")).
   settings(

sbt/src/sbt-test/tests/nested-inproc-par/build.sbt

@@ -1,6 +1,6 @@
 val scalatest = "org.scalatest" %% "scalatest" % "3.0.5"
 
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 lazy val root = (project in file("."))
   .settings(

sbt/src/sbt-test/tests/nested-inproc-seq/build.sbt

@@ -1,6 +1,6 @@
 val scalatest = "org.scalatest" %% "scalatest" % "3.0.5"
 
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 lazy val root = (project in file("."))
   .settings(

sbt/src/sbt-test/tests/nested-subproc/build.sbt

@@ -1,7 +1,7 @@
 val scalatest = "org.scalatest" %% "scalatest" % "3.0.5"
 val scalaxml = "org.scala-lang.modules" %% "scala-xml" % "1.1.1"
 
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 lazy val root = (project in file("."))
   .settings(

sbt/src/sbt-test/tests/nested-tests/build.sbt

@@ -1,6 +1,6 @@
 val scalcheck = "org.scalacheck" %% "scalacheck" % "1.14.0"
 
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 ThisBuild / version := "0.0.1" 
 ThisBuild / organization := "org.catastrophe"
 

sbt/src/sbt-test/tests/one-class-multi-framework/build.sbt

@@ -1,5 +1,5 @@
 val specsJunit = "org.specs2" %% "specs2-junit" % "4.3.4"
 val junitinterface = "com.novocode" % "junit-interface" % "0.11"
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 libraryDependencies += junitinterface % Test
 libraryDependencies += specsJunit % Test

sbt/src/sbt-test/tests/order/build.sbt

@@ -1,5 +1,5 @@
 val scalcheck = "org.scalacheck" %% "scalacheck" % "1.14.0"
 
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 Test / parallelExecution := false
 libraryDependencies += scalcheck % Test

sbt/src/sbt-test/tests/resources/build.sbt

@@ -1,3 +1,3 @@
 val specs = "org.specs2" %% "specs2-core" % "4.3.4"
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 libraryDependencies += specs % Test

sbt/src/sbt-test/tests/scala-instance-classloader/build.sbt

@@ -3,7 +3,7 @@ import sbt.internal.inc.ScalaInstance
 lazy val OtherScala = config("other-scala").hide
 lazy val junitinterface = "com.novocode" % "junit-interface" % "0.11"
 lazy val akkaActor = "com.typesafe.akka" %% "akka-actor" % "2.5.17"
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 lazy val root = (project in file("."))
   .configs(OtherScala)

sbt/src/sbt-test/tests/serial/build.sbt

@@ -1,6 +1,6 @@
 val scalatest = "org.scalatest" %% "scalatest" % "3.0.5"
 
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 ThisBuild / organization := "com.example"
 ThisBuild / version      := "0.0.1-SNAPSHOT"
 

sbt/src/sbt-test/tests/setup-cleanup/base.sbt

@@ -1,3 +1,3 @@
 val scalatest = "org.scalatest" %% "scalatest" % "3.0.5"
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 libraryDependencies += scalatest

sbt/src/sbt-test/tests/single-runner/build.sbt

@@ -1,4 +1,4 @@
 val scalatest = "org.scalatest" %% "scalatest" % "3.0.5"
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 libraryDependencies += scalatest
 Test / testOptions += Tests.Argument("-C", "custom.CustomReporter")

sbt/src/sbt-test/tests/specs-run/build.sbt

@@ -1,4 +1,4 @@
 val specs = "org.specs2" %% "specs2-core" % "4.3.4"
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 libraryDependencies += specs % Test

sbt/src/sbt-test/tests/t543/build.sbt

@@ -7,7 +7,7 @@ val check = TaskKey[Unit]("check", "Check correct error has been returned.")
 val scalatest = "org.scalatest" %% "scalatest" % "3.0.5"
 val scalaxml = "org.scala-lang.modules" %% "scala-xml" % "1.1.1"
 
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 lazy val root = (project in file(".")).
   settings(

sbt/src/sbt-test/tests/task/build.sbt

@@ -1,4 +1,4 @@
 val scalatest = "org.scalatest" %% "scalatest" % "3.0.5"
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 libraryDependencies += scalatest
 Test / testOptions += Tests.Argument("-C", "custom.CustomReporter")

sbt/src/sbt-test/tests/test-exclude/build.sbt

@@ -1,5 +1,5 @@
 val scalatest = "org.scalatest" %% "scalatest" % "3.0.5"
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 lazy val root = (project in file("."))
   .settings(

sbt/src/sbt-test/tests/test-quick/build.sbt

@@ -1,6 +1,6 @@
 val scalatest = "org.scalatest" %% "scalatest" % "3.0.5"
 val scalaxml = "org.scala-lang.modules" %% "scala-xml" % "1.1.1"
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 lazy val root = (project in file("."))
   .settings(

sbt/src/sbt-test/watch/commands/build.sbt

@@ -53,4 +53,4 @@ expectFailure / watchOnFileInputEvent := { (_, e) =>
 }
 
 
-crossScalaVersions := Seq("2.11.12", "2.12.11")
+crossScalaVersions := Seq("2.11.12", "2.12.12")

sbt/src/test/scala/sbt/IllegalReferenceSpec.scala

@@ -66,7 +66,7 @@ class IllegalReferenceSpec extends fixture.FunSuite with fixture.TestDataFixture
          |  // `Def.toITask(sbt.Keys.baseDirectory)`. This, in turn, causes `Def` to be added
          |  // to a list of local definitions. Later on, we dereference `Def` with
          |  // `Def.sequential` which used to erroneously cause an illegal dynamic reference.
-         |  baseDirectory.value
+         |  Def.unit(baseDirectory.value)
          |  Def.sequential(Def.task(42))
          |}.dependencies.headOption.map(_.key.label)
        """.stripMargin

server-test/src/server-test/handshake/build.sbt

@@ -1,6 +1,6 @@
 import sbt.internal.server.{ ServerHandler, ServerIntent }
 
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 lazy val root = (project in file("."))
   .settings(

server-test/src/server-test/response/build.sbt

@@ -1,6 +1,6 @@
 import sbt.internal.server.{ ServerHandler, ServerIntent }
 
-ThisBuild / scalaVersion := "2.12.11"
+ThisBuild / scalaVersion := "2.12.12"
 
 Global / serverLog / logLevel := Level.Debug
 // custom handler