Use Hamcrest assertions instead of JUnit in common/reactive - backport 2.x (#1749)

common/reactive/src/test/java/io/helidon/common/reactive/IgnoreElementsTest.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2021 Oracle and/or its affiliates.
+ * Copyright (c) 2022 Oracle and/or its affiliates.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -27,7 +27,7 @@
 import java.util.concurrent.atomic.AtomicInteger;
 
 import static org.hamcrest.MatcherAssert.assertThat;
-import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.hamcrest.CoreMatchers.is;
 
 import org.hamcrest.Matchers;
 import org.junit.jupiter.api.Test;
@@ -40,7 +40,7 @@ void multiIgnoreTriggerSubscription() throws InterruptedException {
                 .peek(i -> latch.countDown())
                 .ignoreElements(); // should trigger subscription on its own
 
-        assertTrue(latch.await(200, TimeUnit.MILLISECONDS));
+        assertThat(latch.await(200, TimeUnit.MILLISECONDS), is(true));
     }
 
     @Test
@@ -50,7 +50,7 @@ void singleIgnoreTriggerSubscription() throws InterruptedException {
                 .peek(i -> latch.countDown())
                 .ignoreElement(); // should trigger subscription on its own
 
-        assertTrue(latch.await(200, TimeUnit.MILLISECONDS));
+        assertThat(latch.await(200, TimeUnit.MILLISECONDS), is(true));
     }
 
     @Test

common/reactive/src/test/java/io/helidon/common/reactive/MultiDefaultIfEmptyTest.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020, 2021 Oracle and/or its affiliates.
+ * Copyright (c) 2020, 2022 Oracle and/or its affiliates.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -19,11 +19,11 @@
 import java.io.IOException;
 import java.util.concurrent.SubmissionPublisher;
 
-import static org.junit.jupiter.api.Assertions.assertFalse;
-import static org.junit.jupiter.api.Assertions.assertTrue;
-
 import org.junit.jupiter.api.Test;
 
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.CoreMatchers.is;
+
 public class MultiDefaultIfEmptyTest {
 
     @Test
@@ -129,13 +129,13 @@ public void cancel() {
                 .defaultIfEmpty(2)
                 .subscribe(ts);
 
-        assertTrue(sp.hasSubscribers());
+        assertThat(sp.hasSubscribers(), is(true));
 
         ts.assertEmpty();
 
         ts.cancel();
 
-        assertFalse(sp.hasSubscribers());
+        assertThat(sp.hasSubscribers(), is(false));
     }
 
     @Test
@@ -147,13 +147,13 @@ public void cancelWithSupplier() {
                 .defaultIfEmpty(() -> 2)
                 .subscribe(ts);
 
-        assertTrue(sp.hasSubscribers());
+        assertThat(sp.hasSubscribers(), is(true));
 
         ts.assertEmpty();
 
         ts.cancel();
 
-        assertFalse(sp.hasSubscribers());
+        assertThat(sp.hasSubscribers(), is(false));
     }
 
 }

common/reactive/src/test/java/io/helidon/common/reactive/MultiFlatMapPublisherTest.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020, 2021 Oracle and/or its affiliates.
+ * Copyright (c) 2020, 2022 Oracle and/or its affiliates.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -30,10 +30,11 @@
 import java.util.stream.IntStream;
 
 import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.contains;
+import static org.hamcrest.Matchers.hasSize;
 import static org.hamcrest.Matchers.instanceOf;
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.nullValue;
-import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.fail;
 
 import org.junit.jupiter.api.RepeatedTest;
@@ -154,7 +155,7 @@ public void delayError() {
 
         ts.requestMax();
 
-        assertEquals(ts.getItems(), Arrays.asList(6));
+        assertThat(ts.getItems(), contains(6));
         assertThat(ts.getLastError(), instanceOf(ArithmeticException.class));
         assertThat(ts.isComplete(), is(false));
     }
@@ -170,7 +171,7 @@ public void delayErrorInner() {
 
         ts.requestMax();
 
-        assertEquals(ts.getItems(), Arrays.asList(6, -6));
+        assertThat(ts.getItems(), contains(6, -6));
         assertThat(ts.getLastError(), instanceOf(ArithmeticException.class));
         assertThat(ts.isComplete(), is(false));
     }
@@ -257,7 +258,7 @@ public void justJust() {
 
         ts.request1();
 
-        assertEquals(ts.getItems(), Collections.singletonList(1));
+        assertThat(ts.getItems(), contains(1));
         assertThat(ts.getLastError(), is(nullValue()));
         assertThat(ts.isComplete(), is(true));
     }
@@ -275,7 +276,7 @@ public void onSubscribe(Flow.Subscription subscription) {
                 .flatMap(Single::just)
                 .subscribe(ts);
 
-        assertEquals(ts.getItems(), Collections.singletonList(1));
+        assertThat(ts.getItems(), contains(1));
         assertThat(ts.getLastError(), is(nullValue()));
         assertThat(ts.isComplete(), is(true));
     }
@@ -307,12 +308,11 @@ public void flatMapCompletionStage() {
 
     @RepeatedTest(500)
     public void multi() throws ExecutionException, InterruptedException {
-        assertEquals(EXPECTED_EMISSION_COUNT, Multi.create(TEST_DATA)
+        assertThat(Multi.create(TEST_DATA)
                 .flatMap(MultiFlatMapPublisherTest::asyncFlowPublisher, MAX_CONCURRENCY, false, PREFETCH)
                 .distinct()
                 .collectList()
-                .await(800, TimeUnit.MILLISECONDS)
-                .size());
+                .await(800, TimeUnit.MILLISECONDS), hasSize(EXPECTED_EMISSION_COUNT));
     }
 
     private static Flow.Publisher<? extends String> asyncFlowPublisher(Integer i) {

common/reactive/src/test/java/io/helidon/common/reactive/MultiRetryTest.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020, 2021 Oracle and/or its affiliates.
+ * Copyright (c) 2020, 2022 Oracle and/or its affiliates.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -22,12 +22,14 @@
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicInteger;
 
-import static org.junit.jupiter.api.Assertions.assertEquals;
-import static org.junit.jupiter.api.Assertions.assertThrows;
-import static org.junit.jupiter.api.Assertions.assertTrue;
-
 import org.junit.jupiter.api.Test;
 
+import static org.hamcrest.Matchers.emptyArray;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.hamcrest.CoreMatchers.is;
+import static org.hamcrest.CoreMatchers.instanceOf;
+import static org.hamcrest.MatcherAssert.assertThat;
+
 public class MultiRetryTest {
 
     @Test
@@ -47,7 +49,7 @@ public void predicate() {
                 .subscribe(ts);
 
         ts.assertFailure(IllegalArgumentException.class);
-        assertEquals(count.get(), 5);
+        assertThat(count.get(), is(5));
     }
 
     @Test
@@ -59,7 +61,7 @@ public void whenFunctionNull() {
                 .subscribe(ts);
 
         ts.assertFailure(NullPointerException.class);
-        assertTrue(ts.getLastError().getSuppressed()[0] instanceof IOException, "" + ts.getLastError());
+        assertThat("" + ts.getLastError(), ts.getLastError().getSuppressed()[0], instanceOf(IOException.class));
     }
 
     @Test
@@ -73,7 +75,7 @@ public void whenFunctionCrash() {
                 .subscribe(ts);
 
         ts.assertFailure(IllegalArgumentException.class);
-        assertTrue(ts.getLastError().getSuppressed()[0] instanceof IOException, "" + ts.getLastError());
+        assertThat("" + ts.getLastError(), ts.getLastError().getSuppressed()[0], instanceOf(IOException.class));
     }
 
     @Test
@@ -87,7 +89,7 @@ public void whenFunctionNoSelfSuppression() {
                 .subscribe(ts);
 
         ts.assertFailure(IllegalArgumentException.class);
-        assertEquals(ts.getLastError().getSuppressed().length, 0, "" + ts.getLastError());
+        assertThat("" + ts.getLastError(), ts.getLastError().getSuppressed(), emptyArray());
     }
 
     @Test
@@ -121,7 +123,7 @@ public void whenFunctionError() {
                 .subscribe(ts);
 
         ts.assertFailure(IllegalArgumentException.class);
-        assertEquals(ts.getLastError().getSuppressed().length, 0, "" + ts.getLastError());
+        assertThat("" + ts.getLastError(), ts.getLastError().getSuppressed(), emptyArray());
     }
 
     @Test
@@ -146,7 +148,7 @@ public void whenFunctionErrorHidden() {
                 .subscribe(ts);
 
         ts.assertFailure(IllegalArgumentException.class);
-        assertEquals(ts.getLastError().getSuppressed().length, 0, "" + ts.getLastError());
+        assertThat("" + ts.getLastError(), ts.getLastError().getSuppressed(), emptyArray());
     }
 
     @Test
@@ -166,7 +168,7 @@ public void timer() {
             ts.awaitDone(5, TimeUnit.SECONDS)
                     .assertResult(1);
 
-            assertEquals(count.get(), 5);
+            assertThat(count.get(), is(5));
         } finally {
             executor.shutdown();
         }

common/reactive/src/test/java/io/helidon/common/reactive/MultiSkipPublisherTest.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020, 2021 Oracle and/or its affiliates.
+ * Copyright (c) 2020, 2022 Oracle and/or its affiliates.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -17,14 +17,14 @@
 
 package io.helidon.common.reactive;
 
-import org.junit.jupiter.api.Test;
+import java.util.Iterator;
 
-import java.util.*;
+import org.junit.jupiter.api.Test;
 
 import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.contains;
 import static org.hamcrest.core.Is.is;
 import static org.hamcrest.core.IsInstanceOf.instanceOf;
-import static org.junit.jupiter.api.Assertions.assertEquals;
 
 public class MultiSkipPublisherTest {
 
@@ -67,7 +67,7 @@ public Object next() {
 
         ts.requestMax();
 
-        assertEquals(ts.getItems(), Collections.singletonList(3));
+        assertThat(ts.getItems(), contains(3));
         assertThat(ts.getLastError(), instanceOf(IllegalArgumentException.class));
         assertThat(ts.isComplete(), is(false));
     }

common/reactive/src/test/java/io/helidon/common/reactive/MultiSwitchIfEmptyTest.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020, 2021 Oracle and/or its affiliates.
+ * Copyright (c) 2020, 2022 Oracle and/or its affiliates.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -19,11 +19,11 @@
 import java.io.IOException;
 import java.util.concurrent.SubmissionPublisher;
 
-import static org.junit.jupiter.api.Assertions.assertFalse;
-import static org.junit.jupiter.api.Assertions.assertTrue;
-
 import org.junit.jupiter.api.Test;
 
+import static org.hamcrest.CoreMatchers.is;
+import static org.hamcrest.MatcherAssert.assertThat;
+
 public class MultiSwitchIfEmptyTest {
 
     @Test
@@ -93,13 +93,13 @@ public void cancel() {
                 .switchIfEmpty(Multi.singleton(2))
                 .subscribe(ts);
 
-        assertTrue(sp.hasSubscribers());
+        assertThat(sp.hasSubscribers(), is(true));
 
         ts.assertEmpty();
 
         ts.cancel();
 
-        assertFalse(sp.hasSubscribers());
+        assertThat(sp.hasSubscribers(), is(false));
     }
 
     @Test
@@ -111,13 +111,13 @@ public void cancelFallback() {
                 .switchIfEmpty(Multi.create(sp))
                 .subscribe(ts);
 
-        assertTrue(sp.hasSubscribers());
+        assertThat(sp.hasSubscribers(), is(true));
 
         ts.assertEmpty();
 
         ts.cancel();
 
-        assertFalse(sp.hasSubscribers());
+        assertThat(sp.hasSubscribers(), is(false));
     }
 
 }

common/reactive/src/test/java/io/helidon/common/reactive/MultiTakeWhilePublisherTest.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020, 2021 Oracle and/or its affiliates.
+ * Copyright (c) 2020, 2022 Oracle and/or its affiliates.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -20,13 +20,12 @@
 import org.junit.jupiter.api.Test;
 
 import java.io.IOException;
-import java.util.Arrays;
 
 import static org.hamcrest.CoreMatchers.instanceOf;
 import static org.hamcrest.CoreMatchers.is;
 import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.contains;
 import static org.hamcrest.core.IsNull.nullValue;
-import static org.junit.jupiter.api.Assertions.assertEquals;
 
 public class MultiTakeWhilePublisherTest {
 
@@ -54,7 +53,7 @@ public void limited() {
 
         ts.requestMax();
 
-        assertEquals(ts.getItems(), Arrays.asList(1, 2, 3));
+        assertThat(ts.getItems(), contains(1, 2, 3));
         assertThat(ts.getLastError(), is(nullValue()));
         assertThat(ts.isComplete(), is(true));
     }