How to apply common test configuration to all projects? - scala

Question

I'm migrating an old project to Scala 3. The build.sbt is as follows:
import Dependencies._
inThisBuild(
Seq(
scalaVersion := "2.12.7",
scalacOptions ++= Seq(
"-unchecked",
// more
)
)
++ inConfig(Test)(Seq(
testOptions += Tests.Argument(TestFrameworks.ScalaTest, "-o", "-e"),
// more
))
)
lazy val root = (project in file("."))
.aggregate(
`test-util`
)
lazy val `test-util` = project
Now, I want to separate stuff inside inThisBuild for legibility.
import Dependencies._
ThisBuild / scalaVersion := "3.0.1"
ThisBuild / scalacOptions ++= Seq(
"-unchecked",
// more
)
lazy val testSettings = inConfig(Test)(
Seq(
testOptions += Tests.Argument(TestFrameworks.ScalaTest, "-o", "-e"),
// more
))
lazy val root = (project in file("."))
.aggregate(
`test-util`
)
.settings(testSettings)
lazy val `test-util` = project
As you can see, I'm having to apply the testSettings for each project. Ideally, I'd like to do something like ThisBuild / Test := testSettings but that is not valid syntax.
Is there a way to apply the testSettings to all projects without having to explicitly set .settings(testSettings)?
Edit:
I understand I can write each line of testSettings with ThisBuild / Test prefix, but I’d rather not repeat the same prefix. I’m looking for something like what I’ve done with scalacOptions.

Answer 1

Is there a way to apply the testSettings to all projects without having to explicitly set .settings(testSettings)
Consider creating an auto plugin which can inject settings automatically in all the sub-projects, for example in project/CommonTestSettings.scala
import sbt._
import Keys._
object CommonTestSettings extends sbt.AutoPlugin {
override def requires = plugins.JvmPlugin
override def trigger = allRequirements
override lazy val projectSettings =
inConfig(Test)(
Seq(
testOptions += Tests.Argument(TestFrameworks.ScalaTest, "-o", "-e")
// more
)
)
}
You can test with show testOptions which should reveal the common settings in all the sub-projects, for example in my project where root aggregates foo and bar I get something like
sbt:sbt-multi-project> show testOptions
[info] foo / Test / testOptions
[info] List(Argument(Some(TestFramework(org.scalatest.tools.Framework, org.scalatest.tools.ScalaTestFramework)),List(-o, -e)))
[info] bar / Test / testOptions
[info] List(Argument(Some(TestFramework(org.scalatest.tools.Framework, org.scalatest.tools.ScalaTestFramework)),List(-o, -e)))
[info] Test / testOptions
[info] List(Argument(Some(TestFramework(org.scalatest.tools.Framework, org.scalatest.tools.ScalaTestFramework)),List(-o, -e)))

Answer 2

As you can done with scalaVersion and scalacOptions, you can do with Test. For example:
lazy val testSettings = inConfig(Test)(
Seq(
testOptions += Tests.Argument(TestFrameworks.ScalaTest, "-o", "-e"),
// more
))
Can be rewritten as:
ThisBuild / Test / testOptions += Test.Argument(TestFrameworks.ScalaTest, "-o", "-e")
Is it this that you want? Or do you want to pass a sequence directly?