[build] Fix reactor#891 Mostly build under JDK9, add JDK9 build in Tr…

…avis CI

This commit builds under both JDK8 and JDK9 in Travis CI.
Minus a couple of caveats, it fixes the JDK9 build with various changes:

Version Bumps
 - Update to Gradle 4.2.1 for full compatibility with JDK9
 - Bump asciidoctor plugin^[1]
 - Bump Mockito^[2] and Jacoco to their latest JDK9-compatible versions
 - Bump AssertJ to 3.8.0^[3]
 - Bump Kotlin Gradle Plugin to 1.5.51^[4]

[1] Asciidoctor Caveat:
***********************
In JDK9, don't build the PDF as no compatible combination of
asciidoctorJ-pdf could be found...

[2] Tests Adaptation, Mockito Caveats:
**************************************
Fix scan tests that use mocks of non-Scannable PARENTs/ACTUALs

Added MockUtils with interfaces that help creating Scannable mocks that
also implement another interface for combinations not naturally found in
production code.

See Mockito issue mockito/mockito#357, which
is probably the cause why these used to pass on JDK 8.

[3] AssertJ Caveat:
*******************
Added workaround to an AssertJ issue in Java 8, see:
assertj/assertj#1046

[4] Kotlin Caveats:
*******************
 - Fixed building of Javadoc under JDK9 polluted by Kotlin classes that
 are deemed invalid by the Java 9 doclet. (these used to be ignored in
 Java 8)
 - Dokka is not building, so we exclude kdocZip (and thus dokka) under
 JDK9 (see Kotlin/dokka#220)

.gitignore

@@ -1,3 +1,7 @@
+#jenv local configuration
+.java-version
+
+.gradletasknamecache
 .DS_Store
 bin
 build
@@ -16,4 +20,4 @@ classes
 exportToHtml
 .pmd
 .ruleset
-.rulesets
+.rulesets

.travis.yml

@@ -1,6 +1,7 @@
 language: java
 jdk:
   - oraclejdk8
+  - oraclejdk9
 
 sudo: required
 

build.gradle

@@ -32,7 +32,7 @@ buildscript {
 }
 
 plugins {
-  id 'org.asciidoctor.convert' version '1.5.2'
+  id 'org.asciidoctor.convert' version '1.5.6'
   id "me.champeau.gradle.jmh" version "0.4.4" apply false
   id "org.jetbrains.dokka" version "0.9.15"
   id "me.champeau.gradle.japicmp" version "0.2.5"
@@ -57,8 +57,8 @@ ext {
   logbackVersion = '1.1.2'
 
   // Testing
-  assertJVersion = '3.6.1'
-  mockitoVersion = '2.7.22'
+  assertJVersion = '3.8.0'
+  mockitoVersion = '2.10.0'
 
   javadocLinks = ["http://docs.oracle.com/javase/8/docs/api/",
 				  "http://docs.oracle.com/javaee/6/api/",
@@ -70,7 +70,6 @@ ext {
 						  'rx;resolution:=optional',
 						  'com.google;resolution:=optional',
 						  '*']
-
 }
 
 configure(subprojects) { p ->
@@ -111,7 +110,7 @@ configure(subprojects) { p ->
   }
 
   jacoco {
-	toolVersion = '0.7.7.201606060606'
+	toolVersion = '0.7.9'
   }
 
   jacocoTestReport {
@@ -288,6 +287,11 @@ project('reactor-core') {
 	options.tags = [ "apiNote:a:API Note:", "implSpec:a:Implementation Requirements:",
 					 "implNote:a:Implementation Note:" ]
 
+	// In Java 9, javadoc generator will complain if it finds invalid class files in the classpath
+	// And Kotlin produces such classes, plus kotlin plugin puts them in the main sourceSet
+	classpath = sourceSets.main.output.filter { !it.absolutePath.contains("kotlin") }
+	classpath += sourceSets.main.compileClasspath
+
 	maxMemory = "1024m"
 	destinationDir = new File(project.buildDir, "docs/javadoc")
   }
@@ -361,7 +365,8 @@ project('reactor-core') {
 	archives sourcesJar
 	archives javadocJar
 	archives docsZip
-	archives kdocZip
+	if (!JavaVersion.current().isJava9Compatible())
+	  archives kdocZip
   }
 
   jacocoTestReport.dependsOn testNG
@@ -423,6 +428,11 @@ project('reactor-test') {
 	options.tags = [ "apiNote:a:API Note:", "implSpec:a:Implementation Requirements:",
 					 "implNote:a:Implementation Note:" ]
 
+	// In Java 9, javadoc generator will complain if it finds invalid class files in the classpath
+	// And Kotlin produces such classes, plus kotlin plugin puts them in the main sourceSet
+	classpath = sourceSets.main.output.filter { !it.absolutePath.contains("kotlin") }
+	classpath += sourceSets.main.compileClasspath
+
 	maxMemory = "1024m"
 	destinationDir = new File(project.buildDir, "docs/javadoc")
   }
@@ -469,7 +479,8 @@ project('reactor-test') {
   }
 
   artifacts {
-	archives kdocZip
+	if (!JavaVersion.current().isJava9Compatible())
+	  archives kdocZip
   }
 
   jar.finalizedBy(japicmp)

gradle/doc.gradle

@@ -21,7 +21,13 @@ configure(rootProject) {
 			include "index.asciidoc"
 		}
 		outputDir file("$buildDir/reactor-code/build/asciidoc")
-		backends = ['html5', 'pdf']
+		//TODO remove once a working combination of asciidoctorj, asciidoctorj-pdf and asciidoctor-gradle-plugin is found
+		if (JavaVersion.current().isJava9Compatible()) {
+		  backends = ['html5']
+		}
+		else {
+		  backends = ['html5', 'pdf']
+		}
 		logDocuments = true
 		options = [
 				doctype: 'book'

gradle/setup.gradle

@@ -16,7 +16,7 @@
 
 task wrapper(type: Wrapper, description: "Create a Gradle self-download wrapper") {
 	group = 'Project Setup'
-	gradleVersion = 4.2
+	gradleVersion = "4.2.1"
 }
 
 configure(subprojects) { p ->

gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,5 @@
-#Tue Sep 26 10:19:46 CEST 2017
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-4.2-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-4.2.1-bin.zip

reactor-core/src/test/java/reactor/core/publisher/DelegateProcessorTest.java

@@ -18,7 +18,6 @@
 
 import org.junit.Test;
 import org.mockito.Mockito;
-import org.reactivestreams.Processor;
 import org.reactivestreams.Publisher;
 import reactor.core.Scannable;
 
@@ -29,7 +28,7 @@ public class DelegateProcessorTest {
 
 	@Test
 	public void scanReturnsDownStreamForParentElseDelegates() {
-		Publisher<?> downstream = Mockito.mock(Publisher.class);
+		Publisher<?> downstream = Mockito.mock(FluxOperator.class);
 
 		IllegalStateException boom = new IllegalStateException("boom");
 		InnerConsumer<?> upstream = Mockito.mock(InnerConsumer.class);

reactor-core/src/test/java/reactor/core/publisher/DirectProcessorTest.java

@@ -18,7 +18,6 @@
 import org.junit.Assert;
 import org.junit.Test;
 import org.reactivestreams.Subscriber;
-import reactor.core.CoreSubscriber;
 import reactor.core.Scannable;
 import reactor.test.StepVerifier;
 import reactor.test.subscriber.AssertSubscriber;
@@ -254,7 +253,7 @@ public void subscriberCancels() {
     @Test
     @SuppressWarnings("unchecked")
     public void scanInner() {
-	    CoreSubscriber<? super String> actual = mock(CoreSubscriber.class);
+	    InnerConsumer<? super String> actual = mock(InnerConsumer.class);
         DirectProcessor<String> parent = new DirectProcessor<>();
 
         DirectProcessor.DirectInner<String> test =

reactor-core/src/test/java/reactor/core/publisher/EmitterProcessorTest.java

@@ -24,6 +24,7 @@
 import java.util.concurrent.atomic.AtomicLong;
 import java.util.concurrent.atomic.AtomicReference;
 import java.util.concurrent.locks.LockSupport;
+import java.util.stream.Stream;
 
 import org.junit.Assert;
 import org.junit.Ignore;
@@ -266,10 +267,15 @@ public void state(){
 		assertThat(tp.getPending()).isEqualTo(0);
 		assertThat(tp.getBufferSize()).isEqualTo(Queues.SMALL_BUFFER_SIZE);
 		assertThat(tp.isCancelled()).isFalse();
-		assertThat(tp.inners()).isEmpty();
+
+		//workaround https://github.com/joel-costigliola/assertj-core/issues/1046
+		Stream inners = tp.inners();
+		assertThat(inners).isEmpty();
 
 		Disposable d1 = tp.subscribe();
-		assertThat(tp.inners()).hasSize(1);
+		//workaround https://github.com/joel-costigliola/assertj-core/issues/1046
+		inners = tp.inners();
+		assertThat(inners).hasSize(1);
 
 		FluxSink<Integer> s = tp.sink();
 

reactor-core/src/test/java/reactor/core/publisher/FluxArrayTest.java

@@ -21,6 +21,7 @@
 import reactor.core.CoreSubscriber;
 import reactor.core.Fuseable;
 import reactor.core.Scannable;
+import reactor.test.MockUtils;
 import reactor.test.subscriber.AssertSubscriber;
 
 import static org.assertj.core.api.Assertions.assertThat;
@@ -94,11 +95,10 @@ public void arrayContainsNull() {
 		  .assertNotComplete();
 	}
 
-
 	@Test
 	public void scanConditionalSubscription() {
 		@SuppressWarnings("unchecked")
-		Fuseable.ConditionalSubscriber<? super Object> subscriber = Mockito.mock(Fuseable.ConditionalSubscriber.class);
+		Fuseable.ConditionalSubscriber<? super Object> subscriber = Mockito.mock(MockUtils.TestScannableConditionalSubscriber.class);
 
 		FluxArray.ArrayConditionalSubscription<Object> test =
 				new FluxArray.ArrayConditionalSubscription<>(subscriber,
@@ -126,7 +126,7 @@ public void scanConditionalSubscription() {
 	@Test
 	public void scanConditionalSubscriptionRequested() {
 		@SuppressWarnings("unchecked")
-		Fuseable.ConditionalSubscriber<? super Object> subscriber = Mockito.mock(Fuseable.ConditionalSubscriber.class);
+		Fuseable.ConditionalSubscriber<? super Object> subscriber = Mockito.mock(MockUtils.TestScannableConditionalSubscriber.class);
 		//the mock will not drain the request, so it can be tested
 		Mockito.when(subscriber.tryOnNext(Mockito.any()))
 		       .thenReturn(false);
@@ -143,7 +143,7 @@ public void scanConditionalSubscriptionRequested() {
 	@Test
 	public void scanConditionalSubscriptionCancelled() {
 		@SuppressWarnings("unchecked")
-		Fuseable.ConditionalSubscriber<? super Object> subscriber = Mockito.mock(Fuseable.ConditionalSubscriber.class);
+		Fuseable.ConditionalSubscriber<? super Object> subscriber = Mockito.mock(MockUtils.TestScannableConditionalSubscriber.class);
 
 		FluxArray.ArrayConditionalSubscription<Object> test =
 				new FluxArray.ArrayConditionalSubscription<>(subscriber, new Object[] {"foo", "bar", "baz"});
@@ -155,7 +155,7 @@ public void scanConditionalSubscriptionCancelled() {
 
 	@Test
 	public void scanSubscription() {
-		@SuppressWarnings("unchecked") CoreSubscriber<String> subscriber = Mockito.mock(CoreSubscriber.class);
+		@SuppressWarnings("unchecked") InnerOperator<String, String> subscriber = Mockito.mock(InnerOperator.class);
 		FluxArray.ArraySubscription<String> test =
 				new FluxArray.ArraySubscription<>(subscriber, new String[] {"foo", "bar", "baz"});
 
@@ -179,7 +179,7 @@ public void scanSubscription() {
 	@Test
 	public void scanSubscriptionCancelled() {
 		@SuppressWarnings("unchecked")
-		CoreSubscriber<String> subscriber = Mockito.mock(CoreSubscriber.class);
+		CoreSubscriber<String> subscriber = Mockito.mock(InnerOperator.class);
 		FluxArray.ArraySubscription<String> test =
 				new FluxArray.ArraySubscription<>(subscriber, new String[] {"foo", "bar", "baz"});
 

reactor-core/src/test/java/reactor/core/publisher/FluxAutoConnectFuseableTest.java

@@ -16,9 +16,13 @@
 
 package reactor.core.publisher;
 
+import java.util.function.Consumer;
+
 import org.junit.Test;
 import org.mockito.Mockito;
+import reactor.core.Disposable;
 import reactor.core.Scannable;
+import reactor.test.MockUtils;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
@@ -27,7 +31,7 @@ public class FluxAutoConnectFuseableTest {
 	@Test
 	public void scanMain() {
 		@SuppressWarnings("unchecked")
-		ConnectableFlux<String> source = Mockito.mock(ConnectableFlux.class);
+		ConnectableFlux<String> source = Mockito.mock(MockUtils.TestScannableConnectableFlux.class);
 		Mockito.when(source.getPrefetch()).thenReturn(888);
 		FluxAutoConnectFuseable<String> test = new FluxAutoConnectFuseable<>(source, 123, d -> { });
 

reactor-core/src/test/java/reactor/core/publisher/FluxAutoConnectTest.java

@@ -22,6 +22,7 @@
 import org.mockito.Mockito;
 import reactor.core.Disposable;
 import reactor.core.Scannable;
+import reactor.test.MockUtils;
 import reactor.test.subscriber.AssertSubscriber;
 
 import static org.assertj.core.api.Assertions.assertThat;
@@ -82,7 +83,7 @@ public void connectAfterMany() {
 	@Test
 	public void scanMain() {
 		@SuppressWarnings("unchecked")
-		ConnectableFlux<String> source = Mockito.mock(ConnectableFlux.class);
+		ConnectableFlux<String> source = Mockito.mock(MockUtils.TestScannableConnectableFlux.class);
 		Mockito.when(source.getPrefetch()).thenReturn(888);
 		FluxAutoConnect<String> test = new FluxAutoConnect<>(source, 123, d -> { });
 

reactor-core/src/test/java/reactor/core/publisher/FluxDistinctTest.java

@@ -30,6 +30,7 @@
 import reactor.core.CoreSubscriber;
 import reactor.core.Fuseable;
 import reactor.core.Scannable;
+import reactor.test.MockUtils;
 import reactor.test.StepVerifier;
 import reactor.test.publisher.FluxOperatorTest;
 import reactor.test.subscriber.AssertSubscriber;
@@ -442,7 +443,7 @@ public void scanSubscriber() {
 	@Test
 	public void scanConditionalSubscriber() {
 		@SuppressWarnings("unchecked")
-		Fuseable.ConditionalSubscriber<String> actual = Mockito.mock(Fuseable.ConditionalSubscriber.class);
+		Fuseable.ConditionalSubscriber<String> actual = Mockito.mock(MockUtils.TestScannableConditionalSubscriber.class);
 		FluxDistinct.DistinctConditionalSubscriber<String, Integer, Set<Integer>> test =
 				new FluxDistinct.DistinctConditionalSubscriber<>(actual, new HashSet<>(), String::hashCode);
 		Subscription parent = Operators.emptySubscription();

reactor-core/src/test/java/reactor/core/publisher/FluxDistinctUntilChangedTest.java

@@ -27,6 +27,7 @@
 import reactor.core.CoreSubscriber;
 import reactor.core.Fuseable;
 import reactor.core.Scannable;
+import reactor.test.MockUtils;
 import reactor.test.publisher.FluxOperatorTest;
 import reactor.test.subscriber.AssertSubscriber;
 
@@ -249,7 +250,7 @@ public void scanSubscriber() {
 	@Test
 	public void scanConditionalSubscriber() {
 		@SuppressWarnings("unchecked")
-		Fuseable.ConditionalSubscriber<String> actual = Mockito.mock(Fuseable.ConditionalSubscriber.class);
+		Fuseable.ConditionalSubscriber<String> actual = Mockito.mock(MockUtils.TestScannableConditionalSubscriber.class);
 		FluxDistinctUntilChanged.DistinctUntilChangedConditionalSubscriber<String, Integer> test = new FluxDistinctUntilChanged.DistinctUntilChangedConditionalSubscriber<>(
 				actual, String::hashCode, Objects::equals);
 		Subscription parent = Operators.emptySubscription();

reactor-core/src/test/java/reactor/core/publisher/FluxErrorTest.java

@@ -39,7 +39,7 @@ public void normalOnRequest() {
 
     @Test
     public void scanSubscription() {
-	    @SuppressWarnings("unchecked") CoreSubscriber<String> subscriber = Mockito.mock(CoreSubscriber.class);
+	    @SuppressWarnings("unchecked") CoreSubscriber<String> subscriber = Mockito.mock(InnerOperator.class);
         FluxErrorOnRequest.ErrorSubscription test =
                 new FluxErrorOnRequest.ErrorSubscription(subscriber, new IllegalStateException("boom"));
 

reactor-core/src/test/java/reactor/core/publisher/FluxFilterFuseableTest.java

@@ -22,6 +22,7 @@
 import reactor.core.CoreSubscriber;
 import reactor.core.Fuseable;
 import reactor.core.Scannable;
+import reactor.test.MockUtils;
 import reactor.test.publisher.FluxOperatorTest;
 
 import static org.assertj.core.api.Assertions.assertThat;
@@ -46,7 +47,7 @@ public void scanSubscriber() {
     @Test
     public void scanConditionalSubscriber() {
         @SuppressWarnings("unchecked")
-        Fuseable.ConditionalSubscriber<String> actual = Mockito.mock(Fuseable.ConditionalSubscriber.class);
+        Fuseable.ConditionalSubscriber<String> actual = Mockito.mock(MockUtils.TestScannableConditionalSubscriber.class);
         FluxFilterFuseable.FilterFuseableConditionalSubscriber<String> test = new FluxFilterFuseable.FilterFuseableConditionalSubscriber<>(actual, t -> true);
         Subscription parent = Operators.emptySubscription();
         test.onSubscribe(parent);

reactor-core/src/test/java/reactor/core/publisher/FluxFilterTest.java

@@ -26,6 +26,7 @@
 import reactor.core.CoreSubscriber;
 import reactor.core.Fuseable;
 import reactor.core.Scannable;
+import reactor.test.MockUtils;
 import reactor.test.publisher.FluxOperatorTest;
 import reactor.test.subscriber.AssertSubscriber;
 
@@ -264,7 +265,7 @@ public void scanSubscriber() {
     @Test
     public void scanConditionalSubscriber() {
 	    @SuppressWarnings("unchecked")
-	    Fuseable.ConditionalSubscriber<String> actual = Mockito.mock(Fuseable.ConditionalSubscriber.class);
+	    Fuseable.ConditionalSubscriber<String> actual = Mockito.mock(MockUtils.TestScannableConditionalSubscriber.class);
         FluxFilter.FilterConditionalSubscriber<String> test = new FluxFilter.FilterConditionalSubscriber<>(actual, t -> true);
         Subscription parent = Operators.emptySubscription();
         test.onSubscribe(parent);

reactor-core/src/test/java/reactor/core/publisher/FluxFlatMapTest.java

@@ -23,6 +23,7 @@
 import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.atomic.AtomicInteger;
 import java.util.concurrent.atomic.AtomicReference;
+import java.util.stream.Stream;
 import java.util.function.Function;
 
 import org.junit.Assert;
@@ -954,7 +955,9 @@ void assertAfterOnCompleteInnerState2(InnerConsumer s) {
 
 	@SuppressWarnings("unchecked")
 	void assertAfterOnSubscribeInnerState(InnerProducer s) {
-		assertThat(s.inners()).hasSize(1);
+		//workaround https://github.com/joel-costigliola/assertj-core/issues/1046
+		Stream inners = s.inners();
+		assertThat(inners).hasSize(1);
 	}
 
 	void assertBeforeOnSubscribeInnerState(InnerConsumer s) {

reactor-core/src/test/java/reactor/core/publisher/FluxFlattenIterableTest.java

@@ -338,7 +338,8 @@ public void testPublishingTwice() {
 
     @Test
     public void scanOperator() {
-        Flux<Integer> source = Flux.range(1, 10);
+        Flux<Integer> source = Flux.range(1, 10).map(i -> i - 1);
+
         FluxFlattenIterable<Integer, Integer> test = new FluxFlattenIterable<>(source, i -> new ArrayList<>(i), 35, Queues.one());
 
         assertThat(test.scan(Scannable.Attr.PARENT)).isSameAs(source);