Version 1.3.0

CHANGES.md

@@ -1,5 +1,25 @@
 # Change log for kotlinx.coroutines
 
+## Version 1.3.0
+
+### Flow
+
+This version is the first stable release with [`Flow`](https://kotlin.github.io/kotlinx.coroutines/kotlinx-coroutines-core/kotlinx.coroutines.flow/-flow/index.html) API.
+
+All `Flow` API not marked with `@FlowPreview` or `@ExperimentalCoroutinesApi` annotations are stable and here to stay.
+Flow declarations marked with `@ExperimentalCoroutinesApi` have [the same guarantees](/docs/compatibility.md#experimental-api) as regular experimental API.
+Please note that API marked with `@FlowPreview` have [weak guarantees](/docs/compatibility.md#flow-preview-api) on source, binary and semantic compatibility.
+
+### Changelog
+
+* A new [guide section](/docs/flow.md) about Flow.
+* `CoroutineDispatcher.asExecutor` extension (#1450).
+* Fixed bug when `select` statement could report the same exception twice (#1433).
+* Fixed context preservation in `flatMapMerge` in a case when collected values were immediately emitted to another flow (#1440).
+* Reactive Flow integrations enclosing files are renamed for better interoperability with Java.
+* Default buffer size in all Flow operators is increased to 64.
+* Kotlin updated to 1.3.50.
+
 ## Version 1.3.0-RC2
 
 ### Flow improvements

README.md

@@ -2,10 +2,10 @@
 
 [![official JetBrains project](https://jb.gg/badges/official.svg)](https://confluence.jetbrains.com/display/ALL/JetBrains+on+GitHub)
 [![GitHub license](https://img.shields.io/badge/license-Apache%20License%202.0-blue.svg?style=flat)](https://www.apache.org/licenses/LICENSE-2.0)
-[![Download](https://api.bintray.com/packages/kotlin/kotlinx/kotlinx.coroutines/images/download.svg?version=1.3.0-RC2) ](https://bintray.com/kotlin/kotlinx/kotlinx.coroutines/1.3.0-RC2)
+[![Download](https://api.bintray.com/packages/kotlin/kotlinx/kotlinx.coroutines/images/download.svg?version=1.3.0) ](https://bintray.com/kotlin/kotlinx/kotlinx.coroutines/1.3.0)
 
 Library support for Kotlin coroutines with [multiplatform](#multiplatform) support.
-This is a companion version for Kotlin `1.3.41` release.
+This is a companion version for Kotlin `1.3.50` release.
 
 ```kotlin
 suspend fun main() = coroutineScope {
@@ -81,15 +81,15 @@ Add dependencies (you can also add other modules that you need):
 <dependency>
     <groupId>org.jetbrains.kotlinx</groupId>
     <artifactId>kotlinx-coroutines-core</artifactId>
-    <version>1.3.0-RC2</version>
+    <version>1.3.0</version>
 </dependency>
 ```
 
 And make sure that you use the latest Kotlin version:
 
 ```xml
 <properties>
-    <kotlin.version>1.3.41</kotlin.version>
+    <kotlin.version>1.3.50</kotlin.version>
 </properties>
 ```
 
@@ -99,15 +99,15 @@ Add dependencies (you can also add other modules that you need):
 
 ```groovy
 dependencies {
-    implementation 'org.jetbrains.kotlinx:kotlinx-coroutines-core:1.3.0-RC2'
+    implementation 'org.jetbrains.kotlinx:kotlinx-coroutines-core:1.3.0'
 }
 ```
 
 And make sure that you use the latest Kotlin version:
 
 ```groovy
 buildscript {
-    ext.kotlin_version = '1.3.41'
+    ext.kotlin_version = '1.3.50'
 }
 ```
 
@@ -125,15 +125,15 @@ Add dependencies (you can also add other modules that you need):
 
 ```groovy
 dependencies {
-    implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:1.3.0-RC2")
+    implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:1.3.0")
 }
 ```
 
 And make sure that you use the latest Kotlin version:
 
 ```groovy
 plugins {
-    kotlin("jvm") version "1.3.41"
+    kotlin("jvm") version "1.3.50"
 }
 ```
 
@@ -144,7 +144,7 @@ Make sure that you have either `jcenter()` or `mavenCentral()` in the list of re
 Core modules of `kotlinx.coroutines` are also available for 
 [Kotlin/JS](#js) and [Kotlin/Native](#native).
 In common code that should get compiled for different platforms, add dependency to  
-[`kotlinx-coroutines-core-common`](https://search.maven.org/artifact/org.jetbrains.kotlinx/kotlinx-coroutines-core-common/1.3.0-RC2/jar)
+[`kotlinx-coroutines-core-common`](https://search.maven.org/artifact/org.jetbrains.kotlinx/kotlinx-coroutines-core-common/1.3.0/jar)
 (follow the link to get the dependency declaration snippet).
 
 ### Android
@@ -153,7 +153,7 @@ Add [`kotlinx-coroutines-android`](ui/kotlinx-coroutines-android)
 module as dependency when using `kotlinx.coroutines` on Android:
 
 ```groovy
-implementation 'org.jetbrains.kotlinx:kotlinx-coroutines-android:1.3.0-RC2'
+implementation 'org.jetbrains.kotlinx:kotlinx-coroutines-android:1.3.0'
 ```
 
 This gives you access to Android [Dispatchers.Main](https://kotlin.github.io/kotlinx.coroutines/kotlinx-coroutines-android/kotlinx.coroutines.android/kotlinx.coroutines.-dispatchers/index.html)
@@ -172,15 +172,15 @@ R8 is a replacement for ProGuard in Android ecosystem, it is enabled by default
 ### JS
 
 [Kotlin/JS](https://kotlinlang.org/docs/reference/js-overview.html) version of `kotlinx.coroutines` is published as 
-[`kotlinx-coroutines-core-js`](https://search.maven.org/artifact/org.jetbrains.kotlinx/kotlinx-coroutines-core-js/1.3.0-RC2/jar)
+[`kotlinx-coroutines-core-js`](https://search.maven.org/artifact/org.jetbrains.kotlinx/kotlinx-coroutines-core-js/1.3.0/jar)
 (follow the link to get the dependency declaration snippet).
 
 You can also use [`kotlinx-coroutines-core`](https://www.npmjs.com/package/kotlinx-coroutines-core) package via NPM. 
 
 ### Native
 
 [Kotlin/Native](https://kotlinlang.org/docs/reference/native-overview.html) version of `kotlinx.coroutines` is published as 
-[`kotlinx-coroutines-core-native`](https://search.maven.org/artifact/org.jetbrains.kotlinx/kotlinx-coroutines-core-native/1.3.0-RC2/jar)
+[`kotlinx-coroutines-core-native`](https://search.maven.org/artifact/org.jetbrains.kotlinx/kotlinx-coroutines-core-native/1.3.0/jar)
 (follow the link to get the dependency declaration snippet).
 
 Only single-threaded code (JS-style) on Kotlin/Native is currently supported. 

benchmarks/src/jmh/kotlin/benchmarks/flow/FlatMapMergeBenchmark.kt

@@ -0,0 +1,47 @@
+/*
+ * Copyright 2016-2019 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license.
+ */
+
+package benchmarks.flow
+
+import kotlinx.coroutines.*
+import kotlinx.coroutines.flow.*
+import org.openjdk.jmh.annotations.*
+import java.util.concurrent.*
+
+@Warmup(iterations = 7, time = 1, timeUnit = TimeUnit.SECONDS)
+@Measurement(iterations = 7, time = 1, timeUnit = TimeUnit.SECONDS)
+@Fork(value = 1)
+@BenchmarkMode(Mode.AverageTime)
+@OutputTimeUnit(TimeUnit.MICROSECONDS)
+@State(Scope.Benchmark)
+open class FlatMapMergeBenchmark {
+
+    // Note: tests only absence of contention on downstream
+
+    @Param("10", "100", "1000")
+    private var iterations = 100
+
+    @Benchmark
+    fun flatMapUnsafe() = runBlocking {
+        benchmarks.flow.scrabble.flow {
+            repeat(iterations) { emit(it) }
+        }.flatMapMerge { value ->
+            flowOf(value)
+        }.collect {
+            if (it == -1) error("")
+        }
+    }
+
+    @Benchmark
+    fun flatMapSafe() = runBlocking {
+        kotlinx.coroutines.flow.flow {
+            repeat(iterations) { emit(it) }
+        }.flatMapMerge { value ->
+            flowOf(value)
+        }.collect {
+            if (it == -1) error("")
+        }
+    }
+
+}

benchmarks/src/jmh/kotlin/benchmarks/flow/misc/Numbers.kt → benchmarks/src/jmh/kotlin/benchmarks/flow/NumbersBenchmark.kt

@@ -3,7 +3,7 @@
  */
 
 
-package benchmarks.flow.misc
+package benchmarks.flow
 
 import benchmarks.flow.scrabble.flow
 import io.reactivex.*
@@ -35,7 +35,7 @@ import java.util.concurrent.*
 @BenchmarkMode(Mode.AverageTime)
 @OutputTimeUnit(TimeUnit.MICROSECONDS)
 @State(Scope.Benchmark)
-open class Numbers {
+open class NumbersBenchmark {
 
     companion object {
         private const val primes = 100

benchmarks/src/jmh/kotlin/benchmarks/flow/misc/SafeFlowBenchmark.kt → benchmarks/src/jmh/kotlin/benchmarks/flow/SafeFlowBenchmark.kt

@@ -2,7 +2,7 @@
  * Copyright 2016-2019 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license.
  */
 
-package benchmarks.flow.misc
+package benchmarks.flow
 
 import kotlinx.coroutines.*
 import kotlinx.coroutines.flow.*

binary-compatibility-validator/reference-public-api/kotlinx-coroutines-core.txt

@@ -293,6 +293,7 @@ public abstract class kotlinx/coroutines/ExecutorCoroutineDispatcher : kotlinx/c
 }
 
 public final class kotlinx/coroutines/ExecutorsKt {
+	public static final fun asExecutor (Lkotlinx/coroutines/CoroutineDispatcher;)Ljava/util/concurrent/Executor;
 	public static final fun from (Ljava/util/concurrent/Executor;)Lkotlinx/coroutines/CoroutineDispatcher;
 	public static final fun from (Ljava/util/concurrent/ExecutorService;)Lkotlinx/coroutines/ExecutorCoroutineDispatcher;
 }
@@ -992,7 +993,7 @@ public final class kotlinx/coroutines/flow/internal/SafeCollectorKt {
 	public static final fun unsafeFlow (Lkotlin/jvm/functions/Function2;)Lkotlinx/coroutines/flow/Flow;
 }
 
-public final class kotlinx/coroutines/flow/internal/SendingCollector : kotlinx/coroutines/flow/internal/ConcurrentFlowCollector {
+public final class kotlinx/coroutines/flow/internal/SendingCollector : kotlinx/coroutines/flow/FlowCollector {
 	public fun <init> (Lkotlinx/coroutines/channels/SendChannel;)V
 	public fun emit (Ljava/lang/Object;Lkotlin/coroutines/Continuation;)Ljava/lang/Object;
 }
@@ -1045,7 +1046,6 @@ public final class kotlinx/coroutines/selects/SelectBuilderImpl : kotlinx/corout
 	public fun invoke (Lkotlinx/coroutines/selects/SelectClause2;Lkotlin/jvm/functions/Function2;)V
 	public fun isSelected ()Z
 	public fun onTimeout (JLkotlin/jvm/functions/Function1;)V
-	public fun performAtomicIfNotSelected (Lkotlinx/coroutines/internal/AtomicDesc;)Ljava/lang/Object;
 	public fun performAtomicTrySelect (Lkotlinx/coroutines/internal/AtomicDesc;)Ljava/lang/Object;
 	public fun resumeSelectCancellableWithException (Ljava/lang/Throwable;)V
 	public fun resumeWith (Ljava/lang/Object;)V
@@ -1068,7 +1068,6 @@ public abstract interface class kotlinx/coroutines/selects/SelectInstance {
 	public abstract fun disposeOnSelect (Lkotlinx/coroutines/DisposableHandle;)V
 	public abstract fun getCompletion ()Lkotlin/coroutines/Continuation;
 	public abstract fun isSelected ()Z
-	public abstract fun performAtomicIfNotSelected (Lkotlinx/coroutines/internal/AtomicDesc;)Ljava/lang/Object;
 	public abstract fun performAtomicTrySelect (Lkotlinx/coroutines/internal/AtomicDesc;)Ljava/lang/Object;
 	public abstract fun resumeSelectCancellableWithException (Ljava/lang/Throwable;)V
 	public abstract fun trySelect (Ljava/lang/Object;)Z

binary-compatibility-validator/reference-public-api/kotlinx-coroutines-reactive.txt

@@ -62,3 +62,8 @@ public final class kotlinx/coroutines/reactive/PublisherCoroutine : kotlinx/coro
 	public fun send (Ljava/lang/Object;Lkotlin/coroutines/Continuation;)Ljava/lang/Object;
 }
 
+public final class kotlinx/coroutines/reactive/ReactiveFlowKt {
+	public static final fun asFlow (Lorg/reactivestreams/Publisher;)Lkotlinx/coroutines/flow/Flow;
+	public static final fun asPublisher (Lkotlinx/coroutines/flow/Flow;)Lorg/reactivestreams/Publisher;
+}
+

binary-compatibility-validator/reference-public-api/kotlinx-coroutines-reactor.txt

@@ -36,6 +36,10 @@ public final class kotlinx/coroutines/reactor/ReactorContextKt {
 	public static final fun asCoroutineContext (Lreactor/util/context/Context;)Lkotlinx/coroutines/reactor/ReactorContext;
 }
 
+public final class kotlinx/coroutines/reactor/ReactorFlowKt {
+	public static final fun asFlux (Lkotlinx/coroutines/flow/Flow;)Lreactor/core/publisher/Flux;
+}
+
 public final class kotlinx/coroutines/reactor/SchedulerCoroutineDispatcher : kotlinx/coroutines/CoroutineDispatcher, kotlinx/coroutines/Delay {
 	public fun <init> (Lreactor/core/scheduler/Scheduler;)V
 	public fun delay (JLkotlin/coroutines/Continuation;)Ljava/lang/Object;

build.gradle

@@ -82,7 +82,8 @@ allprojects {
         ext.kotlin_version = rootProject.properties['kotlin_snapshot_version']
         println "Using Kotlin $kotlin_version for project $it"
 
-        if (version != atomicfu_version) {
+        def skipSnapshotChecks = rootProject.properties['skip_snapshot_checks'] != null
+        if (!skipSnapshotChecks && version != atomicfu_version) {
             throw new IllegalStateException("Current deploy version is $version, but atomicfu version is not overridden ($atomicfu_version) for $it")
         }