!str - replaces flattenConcat with flatMapConcat

akka-stream-tests/src/test/java/akka/stream/javadsl/FlowTest.java

@@ -10,6 +10,7 @@ import akka.japi.JavaPartialFunction;
 import akka.japi.Pair;
 import akka.japi.function.*;
 import akka.stream.*;
+import akka.stream.impl.ConstantFun;
 import akka.stream.javadsl.FlowGraph.Builder;
 import akka.stream.stage.*;
 import akka.stream.testkit.AkkaSpec;
@@ -481,12 +482,12 @@ public class FlowTest extends StreamTest {
     final Iterable<Integer> input1 = Arrays.asList(1, 2, 3);
     final Iterable<Integer> input2 = Arrays.asList(4, 5);
 
-    final List<Source<Integer, BoxedUnit>> mainInputs = new ArrayList<Source<Integer,BoxedUnit>>();
+    final List<Source<Integer, ?>> mainInputs = new ArrayList<Source<Integer,?>>();
     mainInputs.add(Source.from(input1));
     mainInputs.add(Source.from(input2));
 
-    final Flow<Source<Integer, BoxedUnit>, List<Integer>, BoxedUnit> flow = Flow.<Source<Integer, BoxedUnit>>create().
-      <Integer>flattenConcat().grouped(6);
+    final Flow<Source<Integer, ?>, List<Integer>, ?> flow = Flow.<Source<Integer, ?>>create().
+      flatMapConcat(ConstantFun.<Source<Integer, ?>>javaIdentityFunction()).grouped(6);
     Future<List<Integer>> future = Source.from(mainInputs).via(flow)
         .runWith(Sink.<List<Integer>>head(), materializer);
 

akka-stream-tests/src/test/java/akka/stream/javadsl/SourceTest.java

@@ -15,6 +15,7 @@ import akka.stream.Graph;
 import akka.stream.OverflowStrategy;
 import akka.stream.StreamTest;
 import akka.stream.UniformFanInShape;
+import akka.stream.impl.ConstantFun;
 import akka.stream.stage.*;
 import akka.stream.testkit.AkkaSpec;
 import akka.stream.testkit.TestPublisher;
@@ -348,12 +349,13 @@ public class SourceTest extends StreamTest {
     final Iterable<Integer> input1 = Arrays.asList(1, 2, 3);
     final Iterable<Integer> input2 = Arrays.asList(4, 5);
 
-    final List<Source<Integer, BoxedUnit>> mainInputs = new ArrayList<Source<Integer,BoxedUnit>>();
+    final List<Source<Integer, ?>> mainInputs = new ArrayList<Source<Integer,?>>();
     mainInputs.add(Source.from(input1));
     mainInputs.add(Source.from(input2));
 
     Future<List<Integer>> future = Source.from(mainInputs)
-      .<Integer>flattenConcat().grouped(6)
+      .<Integer>flatMapConcat(ConstantFun.<Source<Integer,?>>javaIdentityFunction())
+      .grouped(6)
       .runWith(Sink.<List<Integer>>head(), materializer);
 
     List<Integer> result = Await.result(future, probe.dilated(FiniteDuration.create(3, TimeUnit.SECONDS)));

akka-stream-tests/src/test/scala/akka/stream/scaladsl/FlowConcatAllSpec.scala

@@ -3,6 +3,8 @@
  */
 package akka.stream.scaladsl
 
+import akka.stream.impl.ConstantFun
+
 import scala.concurrent.duration._
 import scala.util.control.NoStackTrace
 import akka.stream.ActorMaterializer
@@ -31,7 +33,7 @@ class FlowConcatAllSpec extends AkkaSpec {
       val main = Source(List(s1, s2, s3, s4, s5))
 
       val subscriber = TestSubscriber.manualProbe[Int]()
-      main.flattenConcat().to(Sink(subscriber)).run()
+      main.flatMapConcat(ConstantFun.scalaIdentityFunction).to(Sink(subscriber)).run()
       val subscription = subscriber.expectSubscription()
       subscription.request(10)
       for (i ← 1 to 10)
@@ -42,7 +44,7 @@ class FlowConcatAllSpec extends AkkaSpec {
 
     "work together with SplitWhen" in {
       val subscriber = TestSubscriber.manualProbe[Int]()
-      Source(1 to 10).splitWhen(_ % 2 == 0).flattenConcat().runWith(Sink(subscriber))
+      Source(1 to 10).splitWhen(_ % 2 == 0).flatMapConcat(ConstantFun.scalaIdentityFunction).runWith(Sink(subscriber))
       val subscription = subscriber.expectSubscription()
       subscription.request(10)
       for (i ← (1 to 10))
@@ -54,7 +56,7 @@ class FlowConcatAllSpec extends AkkaSpec {
     "on onError on master stream cancel the current open substream and signal error" in assertAllStagesStopped {
       val publisher = TestPublisher.manualProbe[Source[Int, _]]()
       val subscriber = TestSubscriber.manualProbe[Int]()
-      Source(publisher).flattenConcat().to(Sink(subscriber)).run()
+      Source(publisher).flatMapConcat(ConstantFun.scalaIdentityFunction).to(Sink(subscriber)).run()
 
       val upstream = publisher.expectSubscription()
       val downstream = subscriber.expectSubscription()
@@ -74,7 +76,7 @@ class FlowConcatAllSpec extends AkkaSpec {
     "on onError on master stream cancel the currently opening substream and signal error" in assertAllStagesStopped {
       val publisher = TestPublisher.manualProbe[Source[Int, _]]()
       val subscriber = TestSubscriber.manualProbe[Int]()
-      Source(publisher).flattenConcat().to(Sink(subscriber)).run()
+      Source(publisher).flatMapConcat(ConstantFun.scalaIdentityFunction).to(Sink(subscriber)).run()
 
       val upstream = publisher.expectSubscription()
       val downstream = subscriber.expectSubscription()
@@ -94,10 +96,27 @@ class FlowConcatAllSpec extends AkkaSpec {
       subUpstream.expectCancellation()
     }
 
+    "on onError on opening substream, cancel the master stream and signal error " in assertAllStagesStopped {
+      val publisher = TestPublisher.manualProbe[Source[Int, _]]()
+      val subscriber = TestSubscriber.manualProbe[Int]()
+      Source(publisher).flatMapConcat(_ ⇒ throw testException).to(Sink(subscriber)).run()
+
+      val upstream = publisher.expectSubscription()
+      val downstream = subscriber.expectSubscription()
+      downstream.request(1000)
+
+      val substreamPublisher = TestPublisher.manualProbe[Int]()
+      val substreamFlow = Source(substreamPublisher)
+      upstream.expectRequest()
+      upstream.sendNext(substreamFlow)
+      subscriber.expectError(testException)
+      upstream.expectCancellation()
+    }
+
     "on onError on open substream, cancel the master stream and signal error " in assertAllStagesStopped {
       val publisher = TestPublisher.manualProbe[Source[Int, _]]()
       val subscriber = TestSubscriber.manualProbe[Int]()
-      Source(publisher).flattenConcat().to(Sink(subscriber)).run()
+      Source(publisher).flatMapConcat(ConstantFun.scalaIdentityFunction).to(Sink(subscriber)).run()
 
       val upstream = publisher.expectSubscription()
       val downstream = subscriber.expectSubscription()
@@ -117,7 +136,7 @@ class FlowConcatAllSpec extends AkkaSpec {
     "on cancellation cancel the current open substream and the master stream" in assertAllStagesStopped {
       val publisher = TestPublisher.manualProbe[Source[Int, _]]()
       val subscriber = TestSubscriber.manualProbe[Int]()
-      Source(publisher).flattenConcat().to(Sink(subscriber)).run()
+      Source(publisher).flatMapConcat(ConstantFun.scalaIdentityFunction).to(Sink(subscriber)).run()
 
       val upstream = publisher.expectSubscription()
       val downstream = subscriber.expectSubscription()
@@ -138,7 +157,7 @@ class FlowConcatAllSpec extends AkkaSpec {
     "on cancellation cancel the currently opening substream and the master stream" in assertAllStagesStopped {
       val publisher = TestPublisher.manualProbe[Source[Int, _]]()
       val subscriber = TestSubscriber.manualProbe[Int]()
-      Source(publisher).flattenConcat().to(Sink(subscriber)).run()
+      Source(publisher).flatMapConcat(ConstantFun.scalaIdentityFunction).to(Sink(subscriber)).run()
 
       val upstream = publisher.expectSubscription()
       val downstream = subscriber.expectSubscription()
@@ -162,7 +181,11 @@ class FlowConcatAllSpec extends AkkaSpec {
       val up = TestPublisher.manualProbe[Source[Int, _]]()
       val down = TestSubscriber.manualProbe[Int]()
 
-      val flowSubscriber = Source.subscriber[Source[Int, _]].flattenConcat().to(Sink(down)).run()
+      val flowSubscriber = Source
+        .subscriber[Source[Int, _]]
+        .flatMapConcat(ConstantFun.scalaIdentityFunction)
+        .to(Sink(down))
+        .run()
 
       val downstream = down.expectSubscription()
       downstream.cancel()