Utility.trim collapse whitespace for adjacent text nodes #73

shared/src/main/scala/scala/xml/Utility.scala

@@ -46,17 +46,24 @@ object Utility extends AnyRef with parsing.TokenTests {
    */
   def trim(x: Node): Node = x match {
     case Elem(pre, lab, md, scp, child@_*) =>
-      val children = child flatMap trimProper
+      val children = combineAdjacentTextNodes(child:_*) flatMap trimProper
       Elem(pre, lab, md, scp, children.isEmpty, children: _*)
   }
 
+  private def combineAdjacentTextNodes(children: Node*): Seq[Node] = {
+    children.foldRight(Seq.empty[Node]) {
+      case (Text(left), Text(right) +: accMinusLast) => Text(left + right) +: accMinusLast
+      case (n, acc) => n +: acc 
+    }
+  }
+
   /**
    * trim a child of an element. `Attribute` values and `Atom` nodes that
    *  are not `Text` nodes are unaffected.
    */
   def trimProper(x: Node): Seq[Node] = x match {
     case Elem(pre, lab, md, scp, child@_*) =>
-      val children = child flatMap trimProper
+      val children = combineAdjacentTextNodes(child:_*) flatMap trimProper
       Elem(pre, lab, md, scp, children.isEmpty, children: _*)
     case Text(s) =>
       new TextBuffer().append(s).toText

shared/src/test/scala/scala/xml/UtilityTest.scala

@@ -194,4 +194,27 @@ class UtilityTest {
   ).toMap.withDefault {
     key: Char => key.toString
   }
+
+  def issue73StartsWithAndEndsWithWSInFirst: Unit = {
+    val x = <div>{Text("    My name is ")}{Text("Harry")}</div>
+    assertEquals(<div>My name is Harry</div>, Utility.trim(x))
+  }
+
+  @Test
+  def issue73EndsWithWSInLast: Unit = {
+    val x = <div>{Text("My name is ")}{Text("Harry    ")}</div>
+    assertEquals(<div>My name is Harry</div>, Utility.trim(x)) 
+  }
+
+  @Test
+  def issue73HasWSInMiddle: Unit = {
+    val x = <div>{Text("My name is")}{Text(" ")}{Text("Harry")}</div>
+    assertEquals(<div>My name is Harry</div>, Utility.trim(x))
+  }
+
+  @Test
+  def issue73HasWSEverywhere: Unit = {
+    val x = <div>{Text("   My name ")}{Text("  is  ")}{Text("  Harry   ")}</div>
+    assertEquals(<div>My name is Harry</div>, Utility.trim(x))
+  }
 }