Fix #49: Add Scala.js support

build.sbt

@@ -1,14 +1,7 @@
 import com.typesafe.tools.mima.plugin.{MimaPlugin, MimaKeys}
 
-scalaModuleSettings
-
-name                       := "scala-xml"
-
-version                    := "1.0.6-SNAPSHOT"
-
-scalaVersion               := crossScalaVersions.value.head
-
-crossScalaVersions         := {
+scalaVersion       in ThisBuild := crossScalaVersions.value.head
+crossScalaVersions in ThisBuild := {
   val java = System.getProperty("java.version")
   if (java.startsWith("1.6.") || java.startsWith("1.7."))
     Seq("2.11.8")
@@ -18,27 +11,30 @@ crossScalaVersions         := {
     sys.error(s"don't know what Scala versions to build on $java")
 }
 
-//reenable -Xfatal-warnings?
-scalacOptions             ++= "-deprecation:false -feature -Xlint:-stars-align,-nullary-unit,_".split("\\s+").to[Seq]
-
-scalacOptions in Test      += "-Xxml:coalescing"
-
-// important!! must come here (why?)
-scalaModuleOsgiSettings
-
-OsgiKeys.exportPackage := Seq(s"scala.xml.*;version=${version.value}")
-
-libraryDependencies += "junit" % "junit" % "4.11" % "test"
-
-libraryDependencies += "com.novocode" % "junit-interface" % "0.10" % "test"
-
-//// testing:
-// used in CompilerErrors test
-libraryDependencies += ("org.scala-lang" % "scala-compiler" % scalaVersion.value % "test").exclude("org.scala-lang.modules", s"scala-xml*")
-
-mimaPreviousVersion := Some("1.0.5")
-
-// You cannot disable JVM test forking when working on scala modules
-// that are distributed with the compiler because of an SBT
-// classloader leaking issue (scala/scala-xml#20 and #112).
-fork in Test := true
+lazy val root = project.in(file("."))
+  .aggregate(xmlJS, xmlJVM)
+  .settings(publish := {}, publishLocal := {})
+
+lazy val xml = crossProject.in(file("."))
+  .settings(
+    name    := "scala-xml",
+    version := "1.0.6-SNAPSHOT",
+    scalacOptions         ++= "-deprecation:false -feature -Xlint:-stars-align,-nullary-unit,_".split("\\s+").to[Seq],
+    scalacOptions in Test  += "-Xxml:coalescing")
+  .jvmSettings(
+    scalaModuleSettings ++
+    scalaModuleOsgiSettings ++
+    List(
+      OsgiKeys.exportPackage := Seq(s"scala.xml.*;version=${version.value}"),
+      libraryDependencies += "junit" % "junit" % "4.11" % "test",
+      libraryDependencies += "com.novocode" % "junit-interface" % "0.10" % "test",
+      libraryDependencies += ("org.scala-lang" % "scala-compiler" % scalaVersion.value % "test").exclude("org.scala-lang.modules", s"scala-xml*"),
+      mimaPreviousVersion := Some("1.0.5"),
+      // You cannot disable JVM test forking when working on scala modules
+      // that are distributed with the compiler because of an SBT
+      // classloader leaking issue (scala/scala-xml#20 and #112).
+      fork in Test := true): _*)
+  .jsConfigure(_.enablePlugins(ScalaJSJUnitPlugin))
+
+lazy val xmlJVM = xml.jvm
+lazy val xmlJS = xml.js

js/src/test/scala/scala/xml/ReuseNodesTest.scala

@@ -0,0 +1,58 @@
+package scala.xml
+
+import scala.xml.transform._
+import org.junit.Test
+import org.junit.Assert.assertTrue
+import org.junit.Assert.assertEquals
+import org.junit.runner.RunWith
+/**
+ * This test verify that after the tranform, the resultant xml node
+ * uses as many old nodes as possible.
+ *
+ * Three transformers class for case -
+ * One for orginal, one for modified, and one proposed which shows
+ * all are equivalent when it comes to reusing as many nodes as possible
+ */
+object ReuseNodesTest {
+
+  class OriginalTranformr(rules: RewriteRule*) extends RuleTransformer(rules:_*) {
+    override def transform(ns: Seq[Node]): Seq[Node] = {
+      val xs = ns.toStream map transform
+      val (xs1, xs2) = xs zip ns span { case (x, n) => unchanged(n, x) }
+
+      if (xs2.isEmpty) ns
+      else (xs1 map (_._2)) ++ xs2.head._1 ++ transform(ns drop (xs1.length + 1))
+    }
+    override def transform(n:Node): Seq[Node] = super.transform(n)
+  }
+
+  class ModifiedTranformr(rules: RewriteRule*) extends RuleTransformer(rules:_*) {
+    override def transform(ns: Seq[Node]): Seq[Node] = {
+      val changed = ns flatMap transform
+
+      if (changed.length != ns.length || (changed, ns).zipped.exists(_ != _)) changed
+      else ns
+    }
+    override def transform(n:Node): Seq[Node] = super.transform(n)
+  }
+
+  class AlternateTranformr(rules: RewriteRule*) extends RuleTransformer(rules:_*) {
+    override def transform(ns: Seq[Node]): Seq[Node] = {
+      val xs = ns.toStream map transform
+      val (xs1, xs2) = xs zip ns span { case (x, n) => unchanged(n, x) }
+
+      if (xs2.isEmpty) ns
+      else (xs1 map (_._2)) ++ xs2.head._1 ++ transform(ns drop (xs1.length + 1))
+    }
+    override def transform(n:Node): Seq[Node] = super.transform(n)
+  }
+
+  def rewriteRule = new RewriteRule {
+    override def transform(n: Node): NodeSeq = n match {
+      case n if n.label == "change" => Elem(
+           n.prefix, "changed", n.attributes, n.scope, n.child.isEmpty, n.child : _*)
+      case _ => n
+    }
+  }
+
+}

js/src/test/scala/scala/xml/XMLSyntaxTest.scala

@@ -0,0 +1,68 @@
+package scala.xml
+
+import org.junit.Test
+import org.junit.Ignore
+import org.junit.runner.RunWith
+import org.junit.runners.JUnit4
+import org.junit.Assert.assertTrue
+import org.junit.Assert.assertFalse
+import org.junit.Assert.assertEquals
+
+class XMLSyntaxTest {
+
+  private def handle[A](x: Node): A = {
+    x.child(0).asInstanceOf[Atom[A]].data
+  }
+
+  @Test
+  def test1(): Unit = {
+    val xNull = <hello>{null}</hello> // these used to be Atom(unit), changed to empty children
+    assertTrue(xNull.child sameElements Nil)
+
+    val x0 = <hello>{}</hello> // these used to be Atom(unit), changed to empty children
+    val x00 = <hello>{ }</hello> //  dto.
+    val xa = <hello>{ "world" }</hello>
+
+    assertTrue(x0.child sameElements Nil)
+    assertTrue(x00.child sameElements Nil)
+    assertEquals("world", handle[String](xa))
+
+    val xb = <hello>{ 1.5 }</hello>
+    assertEquals(1.5, handle[Double](xb), 0.0)
+
+    val xc = <hello>{ 5 }</hello>
+    assertEquals(5, handle[Int](xc))
+
+    val xd = <hello>{ true }</hello>
+    assertEquals(true, handle[Boolean](xd))
+
+    val xe = <hello>{ 5:Short }</hello>
+    assertEquals((5:Short), handle[Short](xe))
+
+    val xf = <hello>{ val x = 27; x }</hello>
+    assertEquals(27, handle[Int](xf))
+
+    val xg = <hello>{ List(1,2,3,4) }</hello>
+    assertEquals("<hello>1 2 3 4</hello>", xg.toString)
+    assertFalse(xg.child.map(_.isInstanceOf[Text]).exists(identity))
+
+    val xh = <hello>{ for(x <- List(1,2,3,4) if x % 2 == 0) yield x }</hello>
+    assertEquals("<hello>2 4</hello>", xh.toString)
+    assertFalse(xh.child.map(_.isInstanceOf[Text]).exists(identity))
+  }
+
+  /** see SVN r13821 (emir): support for <elem key={x:Option[Seq[Node]]} />,
+   *  so that Options can be used for optional attributes.
+   */
+  @Test
+  def test2(): Unit = {
+    val x1: Option[Seq[Node]] = Some(<b>hello</b>)
+    val n1 = <elem key={x1} />;
+    assertEquals(x1, n1.attribute("key"))
+
+    val x2: Option[Seq[Node]] = None
+    val n2 = <elem key={x2} />;
+    assertEquals(x2, n2.attribute("key"))
+  }
+
+}