Rename fromIterator to enumerate

As @sadache suggested renamed o enumerate. Adding a parameter to the apply is not without breaking the current API though.
playframework · Jan 8, 2013 · a066b3a · a066b3a
1 parent ae1cf8c
commit a066b3a
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Showing 2 changed files with 39 additions and 24 deletions.
diff --git a/framework/src/iteratees/src/main/scala/play/api/libs/iteratee/Enumerator.scala b/framework/src/iteratees/src/main/scala/play/api/libs/iteratee/Enumerator.scala
@@ -540,24 +540,6 @@ object Enumerator {
     fromStream(new java.io.FileInputStream(file), chunkSize)
   }
 
-  /**
-   *  Creates an enumerator from a TraversableOnce object. 
-   */
-  def fromTraversableOnce[A](traversable: scala.collection.TraversableOnce[A])(implicit ctx:scala.concurrent.ExecutionContext): Enumerator[A] = { 
-    val it = traversable.toIterator
-    Enumerator.unfoldM[scala.collection.Iterator[A], A](it: scala.collection.Iterator[A] )({ currentIt => 
-      if(currentIt.hasNext)
-        Future[ Option[(scala.collection.Iterator[A], A)] ]({
-          val next = currentIt.next
-          Some( (currentIt -> next) )
-        })(ctx)
-      else 
-        Future.successful[ Option[(scala.collection.Iterator[A], A)] ]({
-          None
-        })
-    })
-  }
-
   /** Create an Enumerator of bytes with an OutputStream.
    */
   def outputStream(a: java.io.OutputStream => Unit): Enumerator[Array[Byte]] = {
@@ -597,7 +579,28 @@ object Enumerator {
 
   }
 
-  def enumerate[E](s:Seq[E]): Enumerator[E] = apply(s:_*)
+  /**
+   * Create an Enumerator from any TraversableOnce like collection of elements.
+   *
+   * Example of an iterator of lines of a file : 
+   * {{{
+   *  val enumerator: Enumerator[String] = Enumerator( scala.io.Source.fromFile("myfile.txt").getLines ) 
+   * }}}
+   */
+  def enumerate[E](traversable : TraversableOnce[E])(implicit ctx:scala.concurrent.ExecutionContext): Enumerator[E]  = {
+    val it = traversable.toIterator
+    Enumerator.unfoldM[scala.collection.Iterator[E], E](it: scala.collection.Iterator[E] )({ currentIt => 
+      if(currentIt.hasNext)
+        Future[ Option[(scala.collection.Iterator[E], E)] ]({
+          val next = currentIt.next
+          Some( (currentIt -> next) )
+        })(ctx)
+      else 
+        Future.successful[ Option[(scala.collection.Iterator[E], E)] ]({
+          None
+        })
+    })
+  }
 
   private def enumerateSeq[E, A]: (Seq[E], Iteratee[E, A]) => Future[Iteratee[E, A]] = { (l, i) =>
     l.foldLeft(Future.successful(i))((i, e) =>

diff --git a/framework/src/iteratees/src/test/scala/play/api/libs/iteratee/EnumeratorsSpec.scala b/framework/src/iteratees/src/test/scala/play/api/libs/iteratee/EnumeratorsSpec.scala
@@ -41,24 +41,36 @@ object EnumeratorsSpec extends Specification {
 
 }
 
-"Enumerator.fromTraversableOnce" should {
+"Enumerator.enumerate " should {
   "generate an Enumerator from a singleton Iterator" in {
     val iterator = scala.collection.Iterator.single[Int](3)
-    val futureOfResult = Enumerator.fromTraversableOnce(iterator) |>>> 
+    val futureOfResult = Enumerator.enumerate(iterator) |>>> 
                          Enumeratee.take(1) &>> 
                          Iteratee.fold(List.empty[Int])((r, e) => e::r)
     val result = Await.result(futureOfResult, Duration.Inf)
     result(0) must equalTo(3)
     result.length must equalTo(1)
   }
 
-  "take as much element as in the iterator " in {
+  "take as much element as in the iterator in the right order" in {
     val iterator = scala.collection.Iterator.range(0, 50)
-    val futureOfResult = Enumerator.fromTraversableOnce(iterator) |>>> 
+    val futureOfResult = Enumerator.enumerate(iterator) |>>> 
                          Enumeratee.take(100) &>> 
-                         Iteratee.fold(List.empty[Int])((r, e) => e::r)
+                         Iteratee.fold(Seq.empty[Int])((r, e) => r :+ e)
     val result = Await.result(futureOfResult, Duration.Inf)
     result.length must equalTo(50)
+    result(0) must equalTo(0)
+    result(49) must equalTo(49)
+  }
+  "work with Seq too" in {
+    val seq = List(1, 2, 3, 7, 42, 666)
+    val futureOfResult = Enumerator.enumerate(seq) |>>> 
+                         Enumeratee.take(100) &>> 
+                         Iteratee.fold(Seq.empty[Int])((r, e) => r :+ e)
+    val result = Await.result(futureOfResult, Duration.Inf)
+    result.length must equalTo(6)
+    result(0) must equalTo(1)
+    result(4) must equalTo(42)
   }
 }