trait Build in package sbt is deprecated: Use .sbt format instead - scala

Question

Using sbt 0.13.5, when opening the project in IntelliJ, there is a warning message
~\myproject\project\Build.scala:5: trait Build in package sbt is
deprecated: Use .sbt format instead
The content of the Build.scala is
import sbt._
object MyBuild extends Build {
lazy val root = Project("MyProject", file("."))
.configs(Configs.all: _*)
.settings(Testing.settings ++ Docs.settings: _*)
}
The Appendix: .scala build definition and the sbt documentation is rather overwhelming.
How to merge my existing Build.scala to build.sbt? Would appreciate any direction to doc/tutorial/examples.

Answer 1

Rename Build.scala to build.sbt and move it up one directory level, so it's at the top rather than inside the project directory.
Then strip out the beginning and end, leaving:
lazy val root = Project("MyProject", file("."))
.configs(Configs.all: _*)
.settings(Testing.settings ++ Docs.settings: _*)
That's the basics.
Then if you want to add more settings, for example:
lazy val root = Project("MyProject", file("."))
.configs(Configs.all: _*)
.settings(
Testing.settings,
Docs.settings,
name := "MyApp",
scalaVersion := "2.11.8"
)
You don't need the :_* thing on sequences of settings anymore in sbt 0.13.13; older versions required it.
The migration guide in the official doc is here: http://www.scala-sbt.org/0.13/docs/Migrating-from-sbt-012x.html#Migrating+from+the+Build+trait