Fixing issue with XMLEventReader.stop failing t...

Fixing issue with XMLEventReader.stop failing to stop the parser thread.
Contributed by Jean-Laurent Huynh, reviewed by extempore. Closes #3881.

3 files changed, 43 insertions, 1 deletions

diff --git a/src/library/scala/xml/pull/XMLEventReader.scala b/src/library/scala/xml/pull/XMLEventReader.scala
index d51202f2d8..100d4fec71 100755..100644
--- a/src/library/scala/xml/pull/XMLEventReader.scala
+++ b/src/library/scala/xml/pull/XMLEventReader.scala
@@ -52,6 +52,7 @@ class XMLEventReader(src: Source) extends ProducerConsumerIterator[XMLEvent]
   // or at least as much as it can fit in the queue.)
   def stop = {
     produce(POISON)
+    parser.pause()
     parserThread.interrupt()
   }
 
@@ -87,8 +88,21 @@ class XMLEventReader(src: Source) extends ProducerConsumerIterator[XMLEvent]
     def entityRef(pos: Int, n: String)                    = setEvent(EvEntityRef(n))
     def text(pos: Int, txt:String)                        = setEvent(EvText(txt))
 
+    // use to make thread sleep on XMLEventReader.stop
+    @volatile private var pauseRequested = false
+    // requesting this thread to sleep so that it can be interrupted.
+    def pause() { pauseRequested = true }
+
     override def run() {
-      curInput = input
+      curInput = new Source {
+        val iter = new Iterator[Char] {
+          def hasNext = input.hasNext
+          def next() = {
+            if (pauseRequested) Thread.sleep(1000)
+            input.next()
+          }
+        }
+      }
       interruptibly { this.initialize.document() }
       setEvent(POISON)
     }
diff --git a/test/files/run/bug3881.check b/test/files/run/bug3881.check
new file mode 100644
index 0000000000..888acde74f
--- /dev/null
+++ b/test/files/run/bug3881.check
@@ -0,0 +1 @@
+1000000 xml events
diff --git a/test/files/run/bug3881.scala b/test/files/run/bug3881.scala
new file mode 100644
index 0000000000..21247492f5
--- /dev/null
+++ b/test/files/run/bug3881.scala
@@ -0,0 +1,27 @@
+object Test {
+
+  def forever() = new io.Source {
+    val iter = "<foo>".iterator ++ new Iterator[Char] {
+      var count = -1
+      val bar = "<bar/>\n"
+      def hasNext = true
+      def next() = {
+        count += 1
+        bar(count % bar.length)
+      }
+    }
+  }
+
+  def main(args: Array[String]): Unit = {
+    val src = forever()
+    val reader = new xml.pull.XMLEventReader(src)
+    var count = 0
+    while (reader.hasNext && count < 1000000) {
+      reader.next
+      count += 1
+    }
+    reader.stop
+    println(count + " xml events")
+  }
+}
+