Correct Stream impl, to be generalized

niloc132 · Nov 7, 2023 · c79ddd8 · c79ddd8
1 parent a4eeaf1
commit c79ddd8
Showing 1 changed file with 12 additions and 2 deletions.
diff --git a/user/super/com/google/gwt/emul/java/util/stream/Stream.java b/user/super/com/google/gwt/emul/java/util/stream/Stream.java
@@ -153,12 +153,17 @@ static <T> Stream<T> iterate(T seed, UnaryOperator<T> f) {
     AbstractSpliterator<T> spliterator =
         new Spliterators.AbstractSpliterator<T>(
             Long.MAX_VALUE, Spliterator.IMMUTABLE | Spliterator.ORDERED) {
+          private boolean first = true;
           private T next = seed;
 
           @Override
           public boolean tryAdvance(Consumer<? super T> action) {
+            if (!first) {
+              next = f.apply(next);
+            }
+            first = false;
+
             action.accept(next);
-            next = f.apply(next);
             return true;
           }
         };
@@ -169,6 +174,7 @@ static <T> Stream<T> iterate(T seed, Predicate<? super T> hasNext, UnaryOperator
     AbstractSpliterator<T> spliterator =
         new Spliterators.AbstractSpliterator<T>(
             Long.MAX_VALUE, Spliterator.IMMUTABLE | Spliterator.ORDERED) {
+          private boolean first = true;
           private T next = seed;
           private boolean terminated = false;
 
@@ -177,12 +183,16 @@ public boolean tryAdvance(Consumer<? super T> action) {
             if (terminated) {
               return false;
             }
+            if (!first) {
+              next = f.apply(next);
+            }
+            first = false;
+
             if (!hasNext.test(next)) {
               terminated = true;
               return false;
             }
             action.accept(next);
-            next = f.apply(next);
             return true;
           }
         };