Use Def.settings (#26945)

project/AkkaBuild.scala

@@ -22,8 +22,9 @@ object AkkaBuild {
 
   val parallelExecutionByDefault = false // TODO: enable this once we're sure it does not break things
 
-  lazy val buildSettings = Dependencies.Versions ++ Seq(
+  lazy val buildSettings = Def.settings(
     organization := "com.typesafe.akka",
+    Dependencies.Versions,
     // use the same value as in the build scope
     version := (version in ThisBuild).value)
 
@@ -44,9 +45,10 @@ object AkkaBuild {
     }
   }
 
-  lazy val rootSettings = Release.settings ++
-    UnidocRoot.akkaSettings ++
-    Protobuf.settings ++ Seq(
+  lazy val rootSettings = Def.settings(
+    Release.settings,
+    UnidocRoot.akkaSettings,
+    Protobuf.settings,
     parallelExecution in GlobalScope := System.getProperty("akka.parallelExecution", parallelExecutionByDefault.toString).toBoolean,
       version in ThisBuild := akkaVersion
   )
@@ -87,18 +89,16 @@ object AkkaBuild {
             overwrite = true)))
     }
 
-  lazy val resolverSettings = {
+  lazy val resolverSettings = Def.settings(
     // should we be allowed to use artifacts published to the local maven repository
     if (System.getProperty("akka.build.useLocalMavenResolver", "false").toBoolean)
-      Seq(resolvers += mavenLocalResolver)
-    else Seq.empty
-  } ++ {
+      resolvers += mavenLocalResolver
+    else Seq.empty,
     // should we be allowed to use artifacts from sonatype snapshots
     if (System.getProperty("akka.build.useSnapshotSonatypeResolver", "false").toBoolean)
-      Seq(resolvers += Resolver.sonatypeRepo("snapshots"))
-    else Seq.empty
-  } ++ Seq(
-    pomIncludeRepository := (_ => false) // do not leak internal repositories during staging
+      resolvers += Resolver.sonatypeRepo("snapshots")
+    else Seq.empty,
+    pomIncludeRepository := (_ => false), // do not leak internal repositories during staging
   )
 
   private def allWarnings: Boolean = System.getProperty("akka.allwarnings", "false").toBoolean
@@ -108,9 +108,11 @@ object AkkaBuild {
   // -XDignore.symbol.file suppresses sun.misc.Unsafe warnings
   final val DefaultJavacOptions = Seq("-encoding", "UTF-8", "-Xlint:unchecked", "-XDignore.symbol.file")
 
-  lazy val defaultSettings = resolverSettings ++
-    TestExtras.Filter.settings ++
-    Protobuf.settings ++ Seq[Setting[_]](
+  lazy val defaultSettings: Seq[Setting[_]] = Def.settings(
+    resolverSettings,
+    TestExtras.Filter.settings,
+    Protobuf.settings,
+
     // compile options
     scalacOptions in Compile ++= DefaultScalacOptions,
     // Makes sure that, even when compiling with a jdk version greater than 8, the resulting jar will not refer to
@@ -229,10 +231,12 @@ object AkkaBuild {
     logBuffered in Test := System.getProperty("akka.logBufferedTests", "false").toBoolean,
 
     // show full stack traces and test case durations
-      testOptions in Test += Tests.Argument("-oDF")) ++
-      mavenLocalResolverSettings ++
-      docLintingSettings ++
-      CrossJava.crossJavaSettings
+    testOptions in Test += Tests.Argument("-oDF"),
+
+    mavenLocalResolverSettings,
+    docLintingSettings,
+    CrossJava.crossJavaSettings,
+  )
 
   lazy val docLintingSettings = Seq(
     javacOptions in compile ++= Seq("-Xdoclint:none"),