Dotty 3.0.0-M1 support

.gitignore

@@ -30,3 +30,5 @@ scala-swing.iml
 .DS_Store
 
 target/
+/.bloop/
+/.bsp/

.travis.yml

@@ -8,6 +8,7 @@ scala:
   - 2.11.12
   - 2.12.11
   - 2.13.3
+  - 3.0.0-M1
 
 env:
   - ADOPTOPENJDK=8

README.md

@@ -5,14 +5,15 @@
 [<img src="https://img.shields.io/maven-central/v/org.scala-lang.modules/scala-swing_2.12.svg?label=latest%20release%20for%202.12"/>](http://search.maven.org/#search%7Cga%7C1%7Cg%3Aorg.scala-lang.modules%20a%3Ascala-swing_2.12)
 [<img src="https://img.shields.io/maven-central/v/org.scala-lang.modules/scala-swing_2.13.svg?label=latest%20release%20for%202.13"/>](http://search.maven.org/#search%7Cga%7C1%7Cg%3Aorg.scala-lang.modules%20a%3Ascala-swing_2.13)
 
-This is now community maintained by [@Sciss](https://github.com/Sciss) and [@benhutchison](https://github.com/benhutchison). If you are interested in helping then contact them or [@adriaanm](https://github.com/adriaanm).
+This is now community maintained by [@Sciss](https://github.com/Sciss) and [@benhutchison](https://github.com/benhutchison). 
+If you are interested in helping then contact them or [@adriaanm](https://github.com/adriaanm).
 
 ## Adding an sbt dependency
 
 To use scala-swing from sbt, add this to your `build.sbt`:
 
 ```
-libraryDependencies += "org.scala-lang.modules" %% "scala-swing" % "2.1.1"
+libraryDependencies += "org.scala-lang.modules" %% "scala-swing" % "3.0.0"
 ```
 
 ## About scala-swing
@@ -113,6 +114,7 @@ new Frame {
   - When using Scala 2.11, you can use the Scala swing 2.0.x releases on JDK 6 or newer.
   - Scala 2.12 requires you to use JDK 8 (that has nothing to do with scala-swing).
 - The `2.1.x` series adds support for Scala 2.13, while dropping Scala 2.10.
+- The `3.0.x` series adds support for Scala 3.0.
 
 The reason to have different major versions is to allow for binary incompatible changes. Also, some java-swing classes were 
 generified in JDK 7 (see [SI-3634](https://issues.scala-lang.org/browse/SI-3634)) and require the scala-swing sources to be adjusted.

build.sbt

@@ -1,29 +1,40 @@
+lazy val scalaTestVersion = "3.2.3"
+
+lazy val commonSettings = Seq(
+  crossScalaVersions := Seq("3.0.0-M1", "2.13.3", "2.12.12", "2.11.12"),
+  scalaVersion       := "2.13.3",
+  scalacOptions     ++= Seq("-deprecation", "-feature"),
+)
+
 lazy val swing = project.in(file("."))
   .settings(ScalaModulePlugin.scalaModuleSettings)
   .settings(ScalaModulePlugin.scalaModuleOsgiSettings)
+  .settings(commonSettings)
   .settings(
     name := "scala-swing",
     OsgiKeys.exportPackage := Seq(s"scala.swing.*;version=${version.value}"),
     scalaModuleMimaPreviousVersion := Some("2.1.0"),
     // set the prompt (for this build) to include the project id.
     ThisBuild / shellPrompt := { state => Project.extract(state).currentRef.project + "> " },
     libraryDependencies ++= Seq(
-      "org.scalatest" %% "scalatest-flatspec" % "3.2.0" % Test,
-      "org.scalatest" %% "scalatest-shouldmatchers" % "3.2.0" % Test,
+      "org.scalatest" %% "scalatest-flatspec"       % scalaTestVersion % Test,
+      "org.scalatest" %% "scalatest-shouldmatchers" % scalaTestVersion % Test,
     ),
     // Adds a `src/main/scala-2.13+` source directory for Scala 2.13 and newer
     // and  a `src/main/scala-2.13-` source directory for Scala version older than 2.13
     Compile / unmanagedSourceDirectories += {
       val sourceDir = (Compile / sourceDirectory).value
       CrossVersion.partialVersion(scalaVersion.value) match {
         case Some((2, n)) if n >= 13 => sourceDir / "scala-2.13+"
+        case Some((3, _))            => sourceDir / "scala-2.13+" // Dotty
         case _                       => sourceDir / "scala-2.13-"
       }
     }
   )
 
 lazy val examples = project.in(file("examples"))
   .dependsOn(swing)
+  .settings(commonSettings)
   .settings(
     scalaVersion := (swing / scalaVersion).value,
     run / fork := true,
@@ -32,6 +43,7 @@ lazy val examples = project.in(file("examples"))
 
 lazy val uitest = project.in(file("uitest"))
   .dependsOn(swing)
+  .settings(commonSettings)
   .settings(
     scalaVersion := (swing / scalaVersion).value,
     run / fork := true,

examples/src/main/scala/scala/swing/examples/LinePainting.scala

@@ -47,11 +47,11 @@ object LinePainting extends SimpleSwingApplication {
     var path = new geom.GeneralPath
 
     def lineTo(p: Point): Unit = {
-      path.lineTo(p.x, p.y); repaint()
+      path.lineTo(p.x.toFloat, p.y.toFloat); repaint()
     }
 
     def moveTo(p: Point): Unit = {
-      path.moveTo(p.x, p.y); repaint()
+      path.moveTo(p.x.toFloat, p.y.toFloat); repaint()
     }
 
     override def paintComponent(g: Graphics2D): Unit = {

examples/src/main/scala/scala/swing/examples/tutorials/components/ButtonHtmlDemo.scala

@@ -88,19 +88,19 @@ class ButtonHtmlDemo extends FlowPanel {
   listenTo(enable)
 
   reactions += {
-    case ButtonClicked(`enable`) => enableMiddle
-    case ButtonClicked(`disable`) => disableMiddle
+    case ButtonClicked(`enable`)  => enableMiddle()
+    case ButtonClicked(`disable`) => disableMiddle()
   }
 
   def enableMiddle(): Unit = {
-    enable.enabled = false
-    middle.enabled = true
-    disable.enabled = true
+    enable  .enabled = false
+    middle  .enabled = true
+    disable .enabled = true
   }
   def disableMiddle(): Unit = {
-    enable.enabled = true
-    middle.enabled = false
-    disable.enabled = false
+    enable  .enabled = true
+    middle  .enabled = false
+    disable .enabled = false
   }
   def createImageIcon(path: String): Option[javax.swing.ImageIcon] = {
     val imgURL: java.net.URL = getClass().getResource(path)