Merge pull request #79 from spotify/roger/Void_task

Add support for CompletionStage<Void> tasks in the ConcurrencyReducer
spotify · Nov 5, 2020 · 0f6c39a · 0f6c39a
2 parents 0cccde6 + e075e40
commit 0f6c39a
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Showing 2 changed files with 13 additions and 3 deletions.
diff --git a/src/main/java/com/spotify/futures/ConcurrencyReducer.java b/src/main/java/com/spotify/futures/ConcurrencyReducer.java
@@ -164,13 +164,13 @@ private void invoke(final CompletableFuture<T> response,
 
     future.whenComplete(
         (result, t) -> {
-          if (result != null) {
+          if (t != null) {
             limit.release();
-            response.complete(result);
+            response.completeExceptionally(t);
             pump();
           } else {
             limit.release();
-            response.completeExceptionally(t);
+            response.complete(result);
             pump();
           }
         });

diff --git a/src/test/java/com/spotify/futures/ConcurrencyReducerTest.java b/src/test/java/com/spotify/futures/ConcurrencyReducerTest.java
@@ -54,6 +54,16 @@ public void testNullJob() throws Exception {
     limiter.add(null);
   }
 
+  @Test()
+  public void testVoidJob() {
+    final ConcurrencyReducer<Void> limiter = ConcurrencyReducer.create(1, 10);
+    final CompletionStage<Void> task = CompletableFuture.completedFuture(null);
+    assertTrue(task.toCompletableFuture().isDone());
+
+    final CompletableFuture<Void> stage = limiter.add(() -> task);
+    assertTrue(stage.isDone());
+  }
+
   @Test
   public void testJobReturnsNull() throws Exception {
     final ConcurrencyReducer<String> limiter = ConcurrencyReducer.create(1, 10);