Adjust build and test flags

Author: HarrisL2

compiler/test/dotty/tools/vulpix/TestConfiguration.scala

@@ -62,7 +62,7 @@ object TestConfiguration {
       Properties.sourcecode
   ))
 
-  lazy val replWithStagingClasspath = 
+  lazy val replWithStagingClasspath =
     replClassPath + File.pathSeparator + mkClasspath(List(Properties.dottyStaging))
 
   def mkClasspath(classpaths: List[String]): String =
@@ -101,7 +101,7 @@ object TestConfiguration {
   val picklingWithCompilerOptions =
     picklingOptions.withClasspath(withCompilerClasspath).withRunClasspath(withCompilerClasspath)
 
-  val explicitNullsOptions = defaultOptions `and` "-Yexplicit-nulls"
+  val explicitNullsOptions = defaultOptions `and` "-language:safeNulls"
 
   /** Default target of the generated class files */
   private def defaultTarget: String = "17"

project/Build.scala

@@ -189,7 +189,7 @@ object Build {
       "-encoding", "UTF8",
       "-language:implicitConversions",
       s"--java-output-version:${Versions.minimumJVMVersion}",
-      "-Yexplicit-nulls",
+      "-language:safeNulls",
       "-Wsafe-init"
     ),
 
@@ -1082,13 +1082,14 @@ object Build {
       // Remove Scala 3 specific settings
       scalacOptions --= Seq(
         "--java-output-version:17",
-        "-Yexplicit-nulls",
-        "-Wsafe-init"
+        "-Wsafe-init",
+        "-language:safeNulls",
       ),
       scalacOptions ++= Seq(
         "-release:17",
         s"-sourcepath:${(Compile / sourceDirectory).value}",
         "-opt:local", // Important: local optimization are fine, inlining is prohibited!
+        "-Yno-explicit-nulls",
       ),
       target := target.value / "scala2-library",
       Compile / sourceDirectory := (Compile / Keys.target).value / "sources" / scalaVersion.value,
@@ -2117,7 +2118,8 @@ object Build {
       // is a project dependency instead
       excludeDependencies += "org.scala-lang" %% "scala3-library",
       javaOptions := (`scala3-compiler-bootstrapped` / javaOptions).value,
-      scalacOptions -= "-Yexplicit-nulls",
+      scalacOptions -= "-language:safeNulls",
+      scalacOptions += "-Yno-explicit-nulls",
     ).
     settings(
       ideTestsCompilerVersion := (`scala3-compiler-nonbootstrapped` / version).value,
@@ -2186,7 +2188,8 @@ object Build {
     settings(
       regularScalaJSProjectSettings,
       bspEnabled := false,
-      scalacOptions --= Seq("-Werror", "-deprecation", "-Yexplicit-nulls"),
+      scalacOptions --= Seq("-Werror", "-deprecation", "-language:safeNulls"),
+      scalacOptions += "-Yno-explicit-nulls",
 
       // Required to run Scala.js tests.
       Test / fork := false,
@@ -2481,7 +2484,8 @@ object Build {
       commonBootstrappedSettings,
       scalaJSUseMainModuleInitializer := true,
       Test / fork := false,
-      scalacOptions -= "-Yexplicit-nulls",
+      scalacOptions -= "-language:safeNulls",
+      scalacOptions += "-Yno-explicit-nulls",
     )
 
   lazy val `scaladoc-js-contributors` = project.in(file("scaladoc-js/contributors")).
@@ -2564,7 +2568,8 @@ object Build {
       Compile/run := (Compile/run).dependsOn(prepareCommunityBuild).evaluated,
       Test / testOnly := ((Test / testOnly) dependsOn prepareCommunityBuild).evaluated,
       Test / test     := ((Test / test    ) dependsOn prepareCommunityBuild).value,
-      scalacOptions -= "-Yexplicit-nulls",
+      scalacOptions -= "-language:safeNulls",
+      scalacOptions += "-Yno-explicit-nulls",
       javaOptions ++= {
         // Propagate the ivy cache directory setting to the tests, which will
         // then propagate it further to the sbt instances they will spawn.

tests/explicit-nulls/pos/i23936.scala

@@ -1,4 +1,4 @@
-//> using options -Yexplicit-nulls
+//> using options -language:safeNulls
 
 sealed abstract class IsSubtypeOfOutput[-A, +B] extends (A => B)
 object IsSubtypeOfOutput:

tests/explicit-nulls/pos/i24440.scala

@@ -1,4 +1,4 @@
-//> using options -Yexplicit-nulls -Werror
+//> using options -language:safeNulls -Werror
 
 trait AwtComponentLogging extends java.awt.Component:
 

tests/neg-deep-subtype/interop-polytypes.scala

@@ -1,4 +1,4 @@
-//> using options -Yexplicit-nulls -Yno-flexible-types
+//> using options -language:safeNulls -Yno-flexible-types
 
 class Foo {
   import java.util.ArrayList

tests/pos/inline-null-wrapper.scala

@@ -1,4 +1,4 @@
-//> using options -Yexplicit-nulls
+//> using options -language:safeNulls
 import annotation.targetName
 
 class A

tests/warn/i20132.future-Left.scala

@@ -1,4 +1,4 @@
-//> using options -Yexplicit-nulls -Yno-flexible-types
+//> using options -Yno-flexible-types
 
 import scala.language.unsafeNulls
 

tests/warn/i20132.stream-Tuple2.safeNulls.scala

@@ -1,4 +1,4 @@
-//> using options -Yexplicit-nulls -Yno-flexible-types
+//> using options -language:safeNulls -Yno-flexible-types
 
 import scala.jdk.CollectionConverters.*
 

tests/warn/i20132.stream-Tuple2.scala

@@ -1,4 +1,4 @@
-//> using options -Yexplicit-nulls -Yno-flexible-types
+//> using options -Yno-flexible-types
 
 // Previously failed because the scrutinee under
 // unsafeNulls/explicit-nulls/no-flexible-types