Cross-compile config module

Author: alexarchambault

build.sc

@@ -42,7 +42,7 @@ object cli extends Cli
 
 object `cli-options`  extends CliOptions
 object `build-macros` extends BuildMacros
-object config         extends Config
+object config         extends Cross[Config](Scala.all: _*)
 object options        extends Options
 object scalaparse     extends ScalaParse
 object directives     extends Directives
@@ -437,16 +437,27 @@ trait Directives extends ScalaCliSbtModule with ScalaCliPublishModule with HasTe
   }
 }
 
-trait Config extends ScalaCliSbtModule
+class Config(val crossScalaVersion: String) extends ScalaCliCrossSbtModule
     with ScalaCliPublishModule
     with ScalaCliScalafixModule {
-  def scalaVersion = Scala.defaultInternal
-  def ivyDeps = super.ivyDeps() ++ Agg(
-    Deps.jsoniterCore
-  )
+  def ivyDeps = {
+    val maybeCollectionCompat =
+      if (crossScalaVersion.startsWith("2.12.")) Seq(Deps.collectionCompat)
+      else Nil
+    super.ivyDeps() ++ maybeCollectionCompat ++ Agg(
+      Deps.jsoniterCore
+    )
+  }
   def compileIvyDeps = super.compileIvyDeps() ++ Agg(
     Deps.jsoniterMacros
   )
+
+  // Disabling Scalafix in 2.13 and 3, so that it doesn't remove
+  // some compatibility-related imports, that are actually only used
+  // in Scala 2.12.
+  def fix(args: String*) =
+    if (crossScalaVersion.startsWith("2.12.")) super.fix(args: _*)
+    else T.command(())
 }
 
 trait Options extends ScalaCliSbtModule with ScalaCliPublishModule with HasTests
@@ -664,7 +675,7 @@ trait Cli extends SbtModule with ProtoBuildModule with CliLaunchers
   def moduleDeps = Seq(
     `build-module`,
     `cli-options`,
-    config,
+    config(Scala.scala3),
     `scala3-graal`(Scala.scala3)
   )
 

modules/config/src/main/scala-2.12/scala/cli/config/Util.scala

@@ -0,0 +1,14 @@
+package scala.cli.config
+
+private[config] object Util {
+
+  implicit class ConfigStringOps(private val s: String) extends AnyVal {
+    def toBooleanOption: Option[Boolean] =
+      try Some(s.toBoolean)
+      catch {
+        case e: IllegalArgumentException =>
+          None
+      }
+  }
+
+}

modules/config/src/main/scala-2.13/scala/cli/config/Util.scala

@@ -0,0 +1,3 @@
+package scala.cli.config
+
+private[config] object Util

modules/config/src/main/scala-3/scala/cli/config/Util.scala

@@ -0,0 +1,3 @@
+package scala.cli.config
+
+private[config] object Util

modules/config/src/main/scala/scala/cli/config/ConfigDb.scala

@@ -1,7 +1,7 @@
 package scala.cli.config
 
-import com.github.plokhotnyuk.jsoniter_scala.core.{Key as _, *}
-import com.github.plokhotnyuk.jsoniter_scala.macros.*
+import com.github.plokhotnyuk.jsoniter_scala.core.{Key => _, _}
+import com.github.plokhotnyuk.jsoniter_scala.macros._
 
 import java.nio.file.attribute.{PosixFilePermission, PosixFilePermissions}
 import java.nio.file.{Files, Path}
@@ -87,7 +87,7 @@ final class ConfigDb private (
             }
             (k, serialize(v0))
         }
-      val sortedMap: Map[String, RawJson] = ListMap.from(keyValues)
+      val sortedMap: Map[String, RawJson] = ListMap.empty ++ keyValues
       writeToArray(sortedMap)(ConfigDb.codec)
     }
 

modules/config/src/main/scala/scala/cli/config/Key.scala

@@ -3,6 +3,8 @@ package scala.cli.config
 import com.github.plokhotnyuk.jsoniter_scala.core._
 import com.github.plokhotnyuk.jsoniter_scala.macros._
 
+import scala.cli.config.Util._
+
 /** A configuration key
   */
 sealed abstract class Key[T] {