2.x: test sync from Observable to Flowable 10/16-1 (#4714)

src/main/java/io/reactivex/CompletableOperator.java

@@ -21,6 +21,7 @@ public interface CompletableOperator {
      * Applies a function to the child CompletableObserver and returns a new parent CompletableObserver.
      * @param observer the child CompletableObservable instance
      * @return the parent CompletableObserver instance
+     * @throws Exception on failure
      */
     CompletableObserver apply(CompletableObserver observer) throws Exception;
 }

src/main/java/io/reactivex/Flowable.java

@@ -3500,7 +3500,7 @@ public static Flowable<Long> rangeLong(long start, long count) {
     }
 
     /**
-     * Returns a Flowable that emits a Boolean value that indicates whether two Publisher sequences are the
+     * Returns a Single that emits a Boolean value that indicates whether two Publisher sequences are the
      * same by comparing the items emitted by each Publisher pairwise.
      * <p>
      * <img width="640" height="385" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/sequenceEqual.png" alt="">
@@ -3523,12 +3523,12 @@ public static Flowable<Long> rangeLong(long start, long count) {
      */
     @BackpressureSupport(BackpressureKind.FULL)
     @SchedulerSupport(SchedulerSupport.NONE)
-    public static <T> Flowable<Boolean> sequenceEqual(Publisher<? extends T> source1, Publisher<? extends T> source2) {
+    public static <T> Single<Boolean> sequenceEqual(Publisher<? extends T> source1, Publisher<? extends T> source2) {
         return sequenceEqual(source1, source2, ObjectHelper.equalsPredicate(), bufferSize());
     }
 
     /**
-     * Returns a Flowable that emits a Boolean value that indicates whether two Publisher sequences are the
+     * Returns a Single that emits a Boolean value that indicates whether two Publisher sequences are the
      * same by comparing the items emitted by each Publisher pairwise based on the results of a specified
      * equality function.
      * <p>
@@ -3549,19 +3549,19 @@ public static <T> Flowable<Boolean> sequenceEqual(Publisher<? extends T> source1
      *            a function used to compare items emitted by each Publisher
      * @param <T>
      *            the type of items emitted by each Publisher
-     * @return a Flowable that emits a Boolean value that indicates whether the two Publisher sequences
+     * @return a Single that emits a Boolean value that indicates whether the two Publisher sequences
      *         are the same according to the specified function
      * @see <a href="http://reactivex.io/documentation/operators/sequenceequal.html">ReactiveX operators documentation: SequenceEqual</a>
      */
     @BackpressureSupport(BackpressureKind.FULL)
     @SchedulerSupport(SchedulerSupport.NONE)
-    public static <T> Flowable<Boolean> sequenceEqual(Publisher<? extends T> source1, Publisher<? extends T> source2,
+    public static <T> Single<Boolean> sequenceEqual(Publisher<? extends T> source1, Publisher<? extends T> source2,
             BiPredicate<? super T, ? super T> isEqual) {
         return sequenceEqual(source1, source2, isEqual, bufferSize());
     }
 
     /**
-     * Returns a Flowable that emits a Boolean value that indicates whether two Publisher sequences are the
+     * Returns a Single that emits a Boolean value that indicates whether two Publisher sequences are the
      * same by comparing the items emitted by each Publisher pairwise based on the results of a specified
      * equality function.
      * <p>
@@ -3584,23 +3584,23 @@ public static <T> Flowable<Boolean> sequenceEqual(Publisher<? extends T> source1
      *            the number of items to prefetch from the first and second source Publisher
      * @param <T>
      *            the type of items emitted by each Publisher
-     * @return a Flowable that emits a Boolean value that indicates whether the two Publisher sequences
+     * @return a Single that emits a Boolean value that indicates whether the two Publisher sequences
      *         are the same according to the specified function
      * @see <a href="http://reactivex.io/documentation/operators/sequenceequal.html">ReactiveX operators documentation: SequenceEqual</a>
      */
     @BackpressureSupport(BackpressureKind.FULL)
     @SchedulerSupport(SchedulerSupport.NONE)
-    public static <T> Flowable<Boolean> sequenceEqual(Publisher<? extends T> source1, Publisher<? extends T> source2,
+    public static <T> Single<Boolean> sequenceEqual(Publisher<? extends T> source1, Publisher<? extends T> source2,
             BiPredicate<? super T, ? super T> isEqual, int bufferSize) {
         ObjectHelper.requireNonNull(source1, "source1 is null");
         ObjectHelper.requireNonNull(source2, "source2 is null");
         ObjectHelper.requireNonNull(isEqual, "isEqual is null");
         ObjectHelper.verifyPositive(bufferSize, "bufferSize");
-        return RxJavaPlugins.onAssembly(new FlowableSequenceEqual<T>(source1, source2, isEqual, bufferSize));
+        return RxJavaPlugins.onAssembly(new FlowableSequenceEqualSingle<T>(source1, source2, isEqual, bufferSize));
     }
 
     /**
-     * Returns a Flowable that emits a Boolean value that indicates whether two Publisher sequences are the
+     * Returns a Single that emits a Boolean value that indicates whether two Publisher sequences are the
      * same by comparing the items emitted by each Publisher pairwise.
      * <p>
      * <img width="640" height="385" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/sequenceEqual.png" alt="">
@@ -3620,12 +3620,12 @@ public static <T> Flowable<Boolean> sequenceEqual(Publisher<? extends T> source1
      *            the number of items to prefetch from the first and second source Publisher
      * @param <T>
      *            the type of items emitted by each Publisher
-     * @return a Flowable that emits a Boolean value that indicates whether the two sequences are the same
+     * @return a Single that emits a Boolean value that indicates whether the two sequences are the same
      * @see <a href="http://reactivex.io/documentation/operators/sequenceequal.html">ReactiveX operators documentation: SequenceEqual</a>
      */
     @BackpressureSupport(BackpressureKind.FULL)
     @SchedulerSupport(SchedulerSupport.NONE)
-    public static <T> Flowable<Boolean> sequenceEqual(Publisher<? extends T> source1, Publisher<? extends T> source2, int bufferSize) {
+    public static <T> Single<Boolean> sequenceEqual(Publisher<? extends T> source1, Publisher<? extends T> source2, int bufferSize) {
         return sequenceEqual(source1, source2, ObjectHelper.equalsPredicate(), bufferSize);
     }
 
@@ -5196,7 +5196,7 @@ public final T blockingLast(T defaultItem) {
     @BackpressureSupport(BackpressureKind.UNBOUNDED_IN)
     @SchedulerSupport(SchedulerSupport.NONE)
     public final Iterable<T> blockingLatest() {
-        return BlockingFlowableLatest.latest(this);
+        return new BlockingFlowableLatest<T>(this);
     }
 
     /**
@@ -5222,7 +5222,7 @@ public final Iterable<T> blockingLatest() {
     @BackpressureSupport(BackpressureKind.UNBOUNDED_IN)
     @SchedulerSupport(SchedulerSupport.NONE)
     public final Iterable<T> blockingMostRecent(T initialItem) {
-        return BlockingFlowableMostRecent.mostRecent(this, initialItem);
+        return new BlockingFlowableMostRecent<T>(this, initialItem);
     }
 
     /**
@@ -5245,7 +5245,7 @@ public final Iterable<T> blockingMostRecent(T initialItem) {
     @BackpressureSupport(BackpressureKind.UNBOUNDED_IN)
     @SchedulerSupport(SchedulerSupport.NONE)
     public final Iterable<T> blockingNext() {
-        return BlockingFlowableNext.next(this);
+        return new BlockingFlowableNext<T>(this);
     }
 
     /**
@@ -5267,7 +5267,7 @@ public final Iterable<T> blockingNext() {
     @BackpressureSupport(BackpressureKind.UNBOUNDED_IN)
     @SchedulerSupport(SchedulerSupport.NONE)
     public final T blockingSingle() {
-        return singleElement().blockingGet();
+        return singleOrError().blockingGet();
     }
 
     /**
@@ -7248,7 +7248,7 @@ public final <K> Flowable<T> distinct(Function<? super T, K> keySelector,
             Callable<? extends Collection<? super K>> collectionSupplier) {
         ObjectHelper.requireNonNull(keySelector, "keySelector is null");
         ObjectHelper.requireNonNull(collectionSupplier, "collectionSupplier is null");
-        return FlowableDistinct.withCollection(this, keySelector, collectionSupplier);
+        return RxJavaPlugins.onAssembly(new FlowableDistinct<T, K>(this, keySelector, collectionSupplier));
     }
 
     /**
@@ -7271,7 +7271,7 @@ public final <K> Flowable<T> distinct(Function<? super T, K> keySelector,
     @BackpressureSupport(BackpressureKind.FULL)
     @SchedulerSupport(SchedulerSupport.NONE)
     public final Flowable<T> distinctUntilChanged() {
-        return FlowableDistinct.<T>untilChanged(this);
+        return new FlowableDistinctUntilChanged<T>(this, Functions.equalsPredicate());
     }
 
     /**
@@ -7299,7 +7299,7 @@ public final Flowable<T> distinctUntilChanged() {
     @SchedulerSupport(SchedulerSupport.NONE)
     public final <K> Flowable<T> distinctUntilChanged(Function<? super T, K> keySelector) {
         ObjectHelper.requireNonNull(keySelector, "keySelector is null");
-        return FlowableDistinct.untilChanged(this, keySelector);
+        return new FlowableDistinctUntilChanged<T>(this, Functions.equalsPredicate(keySelector));
     }
 
     /**
@@ -13734,7 +13734,7 @@ public final Single<List<T>> toList(final int capacityHint) {
     }
 
     /**
-     * Returns a Flowable that emits a single item, a list composed of all the items emitted by the source
+     * Returns a Single that emits a single item, a list composed of all the items emitted by the source
      * Publisher.
      * <p>
      * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/toList.png" alt="">
@@ -13758,15 +13758,15 @@ public final Single<List<T>> toList(final int capacityHint) {
      * @param <U> the subclass of a collection of Ts
      * @param collectionSupplier
      *               the Callable returning the collection (for each individual Subscriber) to be filled in
-     * @return a Flowable that emits a single item: a List containing all of the items emitted by the source
+     * @return a Single that emits a single item: a List containing all of the items emitted by the source
      *         Publisher
      * @see <a href="http://reactivex.io/documentation/operators/to.html">ReactiveX operators documentation: To</a>
      */
     @BackpressureSupport(BackpressureKind.UNBOUNDED_IN)
     @SchedulerSupport(SchedulerSupport.NONE)
-    public final <U extends Collection<? super T>> Flowable<U> toList(Callable<U> collectionSupplier) {
+    public final <U extends Collection<? super T>> Single<U> toList(Callable<U> collectionSupplier) {
         ObjectHelper.requireNonNull(collectionSupplier, "collectionSupplier is null");
-        return RxJavaPlugins.onAssembly(new FlowableToList<T, U>(this, collectionSupplier));
+        return RxJavaPlugins.onAssembly(new FlowableToListSingle<T, U>(this, collectionSupplier));
     }
 
     /**

src/main/java/io/reactivex/FlowableOperator.java

@@ -26,6 +26,7 @@ public interface FlowableOperator<Downstream, Upstream> {
      * Applies a function to the child Subscriber and returns a new parent Subscriber.
      * @param observer the child Subscriber instance
      * @return the parent Subscriber instance
+     * @throws Exception on failure
      */
     Subscriber<? super Upstream> apply(Subscriber<? super Downstream> observer) throws Exception;
 }

src/main/java/io/reactivex/MaybeOperator.java

@@ -24,6 +24,7 @@ public interface MaybeOperator<Downstream, Upstream> {
      * Applies a function to the child MaybeObserver and returns a new parent MaybeObserver.
      * @param observer the child MaybeObserver instance
      * @return the parent MaybeObserver instance
+     * @throws Exception on failure
      */
     MaybeObserver<? super Upstream> apply(MaybeObserver<? super Downstream> observer) throws Exception;
 }

src/main/java/io/reactivex/ObservableOperator.java

@@ -24,6 +24,7 @@ public interface ObservableOperator<Downstream, Upstream> {
      * Applies a function to the child Observer and returns a new parent Observer.
      * @param observer the child Observer instance
      * @return the parent Observer instance
+     * @throws Exception on failure
      */
     Observer<? super Upstream> apply(Observer<? super Downstream> observer) throws Exception;
 }

src/main/java/io/reactivex/SingleOperator.java

@@ -24,6 +24,7 @@ public interface SingleOperator<Downstream, Upstream> {
      * Applies a function to the child SingleObserver and returns a new parent SingleObserver.
      * @param observer the child SingleObserver instance
      * @return the parent SingleObserver instance
+     * @throws Exception on failure
      */
     SingleObserver<? super Upstream> apply(SingleObserver<? super Downstream> observer) throws Exception;
 }

src/main/java/io/reactivex/internal/fuseable/QueueDisposable.java

@@ -51,66 +51,5 @@
  * </ul>
  * @param <T> the value type transmitted through the queue
  */
-public interface QueueDisposable<T> extends SimpleQueue<T>, Disposable {
-    /**
-     * Returned by the {@link #requestFusion(int)} if the upstream doesn't support
-     * the requested mode.
-     */
-    int NONE = 0;
-
-    /**
-     * Request a synchronous fusion mode and can be returned by {@link #requestFusion(int)}
-     * for an accepted mode.
-     * <p>
-     * In synchronous fusion, all upstream values are either already available or is generated
-     * when {@link #poll()} is called synchronously. When the {@link #poll()} returns null,
-     * that is the indication if a terminated stream.
-     * In this mode, the upstream won't call the onXXX methods and callers of
-     * {@link #poll()} should be prepared to catch exceptions. Note that {@link #poll()} has
-     * to be called sequentially (from within a serializing drain-loop).
-     */
-    int SYNC = 1;
-
-    /**
-     * Request an asynchronous fusion mode and can be returned by {@link #requestFusion(int)}
-     * for an accepted mode.
-     * <p>
-     * In asynchronous fusion, upstream values may become available to {@link #poll()} eventually.
-     * Upstream signals onError() and onComplete() as usual but onNext may not actually contain
-     * the upstream value but have {@code null} instead. Downstream should treat such onNext as indication
-     * that {@link #poll()} can be called. Note that {@link #poll()} has to be called sequentially
-     * (from within a serializing drain-loop). In addition, callers of {@link #poll()} should be
-     * prepared to catch exceptions.
-     */
-    int ASYNC = 2;
-
-    /**
-     * Request any of the {@link #SYNC} or {@link #ASYNC} modes.
-     */
-    int ANY = SYNC | ASYNC;
-
-    /**
-     * Used in binary or combination with the other constants as an input to {@link #requestFusion(int)}
-     * indicating that the {@link #poll()} will be called behind an asynchronous boundary and thus
-     * may change the non-trivial computation locations attached to the {@link #poll()} chain of
-     * fused operators.
-     * <p>
-     * For example, fusing map() and observeOn() may move the computation of the map's function over to
-     * the thread run after the observeOn(), which is generally unexpected.
-     */
-    int BOUNDARY = 4;
-
-    /**
-     * Request a fusion mode from the upstream.
-     * <p>
-     * This should be called before {@code onSubscribe} returns.
-     * <p>
-     * Calling this method multiple times or after {@code onSubscribe} finished is not allowed
-     * and may result in undefined behavior.
-     * <p>
-     * @param mode the requested fusion mode, allowed values are {@link #SYNC}, {@link #ASYNC},
-     * {@link #ANY} combined with {@link #BOUNDARY} (e.g., {@code requestFusion(SYNC | BOUNDARY)}).
-     * @return the established fusion mode: {@link #NONE}, {@link #SYNC}, {@link #ASYNC}.
-     */
-    int requestFusion(int mode);
+public interface QueueDisposable<T> extends QueueFuseable<T>, Disposable {
 }

src/main/java/io/reactivex/internal/fuseable/QueueFuseable.java

@@ -0,0 +1,84 @@
+/**
+ * Copyright 2016 Netflix, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in
+ * compliance with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under the License is
+ * distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See
+ * the License for the specific language governing permissions and limitations under the License.
+ */
+
+package io.reactivex.internal.fuseable;
+
+
+/**
+ * Represents a SimpleQueue plus the means and constants for requesting a fusion mode.
+ * @param <T> the value type returned by the SimpleQueue.poll()
+ */
+public interface QueueFuseable<T> extends SimpleQueue<T> {
+    /**
+     * Returned by the {@link #requestFusion(int)} if the upstream doesn't support
+     * the requested mode.
+     */
+    int NONE = 0;
+
+    /**
+     * Request a synchronous fusion mode and can be returned by {@link #requestFusion(int)}
+     * for an accepted mode.
+     * <p>
+     * In synchronous fusion, all upstream values are either already available or is generated
+     * when {@link #poll()} is called synchronously. When the {@link #poll()} returns null,
+     * that is the indication if a terminated stream.
+     * In this mode, the upstream won't call the onXXX methods and callers of
+     * {@link #poll()} should be prepared to catch exceptions. Note that {@link #poll()} has
+     * to be called sequentially (from within a serializing drain-loop).
+     */
+    int SYNC = 1;
+
+    /**
+     * Request an asynchronous fusion mode and can be returned by {@link #requestFusion(int)}
+     * for an accepted mode.
+     * <p>
+     * In asynchronous fusion, upstream values may become available to {@link #poll()} eventually.
+     * Upstream signals onError() and onComplete() as usual but onNext may not actually contain
+     * the upstream value but have {@code null} instead. Downstream should treat such onNext as indication
+     * that {@link #poll()} can be called. Note that {@link #poll()} has to be called sequentially
+     * (from within a serializing drain-loop). In addition, callers of {@link #poll()} should be
+     * prepared to catch exceptions.
+     */
+    int ASYNC = 2;
+
+    /**
+     * Request any of the {@link #SYNC} or {@link #ASYNC} modes.
+     */
+    int ANY = SYNC | ASYNC;
+
+    /**
+     * Used in binary or combination with the other constants as an input to {@link #requestFusion(int)}
+     * indicating that the {@link #poll()} will be called behind an asynchronous boundary and thus
+     * may change the non-trivial computation locations attached to the {@link #poll()} chain of
+     * fused operators.
+     * <p>
+     * For example, fusing map() and observeOn() may move the computation of the map's function over to
+     * the thread run after the observeOn(), which is generally unexpected.
+     */
+    int BOUNDARY = 4;
+
+    /**
+     * Request a fusion mode from the upstream.
+     * <p>
+     * This should be called before {@code onSubscribe} returns.
+     * <p>
+     * Calling this method multiple times or after {@code onSubscribe} finished is not allowed
+     * and may result in undefined behavior.
+     * <p>
+     * @param mode the requested fusion mode, allowed values are {@link #SYNC}, {@link #ASYNC},
+     * {@link #ANY} combined with {@link #BOUNDARY} (e.g., {@code requestFusion(SYNC | BOUNDARY)}).
+     * @return the established fusion mode: {@link #NONE}, {@link #SYNC}, {@link #ASYNC}.
+     */
+    int requestFusion(int mode);
+
+}