Qualities to test cancellation, closes #132 (#144)

confidence-rxjava3/src/main/java/org/saynotobugs/confidence/rxjava3/RxSubjectAdapter.java

@@ -18,12 +18,11 @@
 
 package org.saynotobugs.confidence.rxjava3;
 
-import org.reactivestreams.Subscriber;
-
 import io.reactivex.rxjava3.core.CompletableObserver;
 import io.reactivex.rxjava3.core.MaybeObserver;
 import io.reactivex.rxjava3.core.Observer;
 import io.reactivex.rxjava3.core.SingleObserver;
+import org.reactivestreams.Subscriber;
 
 
 /**
@@ -39,4 +38,6 @@ public interface RxSubjectAdapter<T>
     void onComplete();
 
     void onError(Throwable error);
+
+    boolean hasSubscribers();
 }

confidence-rxjava3/src/main/java/org/saynotobugs/confidence/rxjava3/RxTestAdapter.java

@@ -18,11 +18,11 @@
 
 package org.saynotobugs.confidence.rxjava3;
 
-import java.util.Collection;
-
 import io.reactivex.rxjava3.observers.TestObserver;
 import io.reactivex.rxjava3.subscribers.TestSubscriber;
 
+import java.util.Collection;
+
 
 /**
  * A generalization of {@link TestObserver} and {@link TestSubscriber}. That provides some means to "acknowledge" already seen emissions.
@@ -48,4 +48,6 @@ public interface RxTestAdapter<T>
     Iterable<Throwable> errors();
 
     boolean isCancelled();
+
+    void cancel();
 }

confidence-rxjava3/src/main/java/org/saynotobugs/confidence/rxjava3/adapters/CompletableSubjectAdapter.java

@@ -18,9 +18,8 @@
 
 package org.saynotobugs.confidence.rxjava3.adapters;
 
-import org.saynotobugs.confidence.rxjava3.RxSubjectAdapter;
-
 import io.reactivex.rxjava3.subjects.CompletableSubject;
+import org.saynotobugs.confidence.rxjava3.RxSubjectAdapter;
 
 
 /**
@@ -58,4 +57,10 @@ public void onError(Throwable error)
     {
         mDelegate.onError(error);
     }
+
+    @Override
+    public boolean hasSubscribers()
+    {
+        return mDelegate.hasObservers();
+    }
 }

confidence-rxjava3/src/main/java/org/saynotobugs/confidence/rxjava3/adapters/MaybeSubjectAdapter.java

@@ -18,9 +18,8 @@
 
 package org.saynotobugs.confidence.rxjava3.adapters;
 
-import org.saynotobugs.confidence.rxjava3.RxSubjectAdapter;
-
 import io.reactivex.rxjava3.subjects.MaybeSubject;
+import org.saynotobugs.confidence.rxjava3.RxSubjectAdapter;
 
 
 public final class MaybeSubjectAdapter<T> implements RxSubjectAdapter<T>
@@ -53,4 +52,10 @@ public void onError(Throwable error)
     {
         mDelegate.onError(error);
     }
+
+    @Override
+    public boolean hasSubscribers()
+    {
+        return mDelegate.hasObservers();
+    }
 }

confidence-rxjava3/src/main/java/org/saynotobugs/confidence/rxjava3/adapters/PublishProcessorAdapter.java

@@ -18,9 +18,8 @@
 
 package org.saynotobugs.confidence.rxjava3.adapters;
 
-import org.saynotobugs.confidence.rxjava3.RxSubjectAdapter;
-
 import io.reactivex.rxjava3.processors.PublishProcessor;
+import org.saynotobugs.confidence.rxjava3.RxSubjectAdapter;
 
 
 /**
@@ -56,4 +55,10 @@ public void onError(Throwable error)
     {
         mDelegate.onError(error);
     }
+
+    @Override
+    public boolean hasSubscribers()
+    {
+        return mDelegate.hasSubscribers();
+    }
 }

confidence-rxjava3/src/main/java/org/saynotobugs/confidence/rxjava3/adapters/PublishSubjectAdapter.java

@@ -18,9 +18,8 @@
 
 package org.saynotobugs.confidence.rxjava3.adapters;
 
-import org.saynotobugs.confidence.rxjava3.RxSubjectAdapter;
-
 import io.reactivex.rxjava3.subjects.PublishSubject;
+import org.saynotobugs.confidence.rxjava3.RxSubjectAdapter;
 
 
 public final class PublishSubjectAdapter<T> implements RxSubjectAdapter<T>
@@ -53,4 +52,10 @@ public void onError(Throwable error)
     {
         mDelegate.onError(error);
     }
+
+    @Override
+    public boolean hasSubscribers()
+    {
+        return mDelegate.hasObservers();
+    }
 }

confidence-rxjava3/src/main/java/org/saynotobugs/confidence/rxjava3/adapters/RxTestObserver.java

@@ -18,15 +18,14 @@
 
 package org.saynotobugs.confidence.rxjava3.adapters;
 
+import io.reactivex.rxjava3.observers.TestObserver;
 import org.saynotobugs.confidence.rxjava3.RxTestAdapter;
 
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.List;
 import java.util.concurrent.atomic.AtomicInteger;
 
-import io.reactivex.rxjava3.observers.TestObserver;
-
 
 public final class RxTestObserver<T> extends TestObserver<T> implements RxTestAdapter<T>
 {
@@ -76,4 +75,10 @@ public boolean isCancelled()
     {
         return super.isDisposed();
     }
+
+    @Override
+    public void cancel()
+    {
+        dispose();
+    }
 }

confidence-rxjava3/src/main/java/org/saynotobugs/confidence/rxjava3/adapters/RxTestSubscriber.java

@@ -18,15 +18,14 @@
 
 package org.saynotobugs.confidence.rxjava3.adapters;
 
+import io.reactivex.rxjava3.subscribers.TestSubscriber;
 import org.saynotobugs.confidence.rxjava3.RxTestAdapter;
 
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.List;
 import java.util.concurrent.atomic.AtomicInteger;
 
-import io.reactivex.rxjava3.subscribers.TestSubscriber;
-
 
 public final class RxTestSubscriber<T> extends TestSubscriber<T> implements RxTestAdapter<T>
 {

confidence-rxjava3/src/main/java/org/saynotobugs/confidence/rxjava3/adapters/SingleSubjectAdapter.java

@@ -18,9 +18,8 @@
 
 package org.saynotobugs.confidence.rxjava3.adapters;
 
-import org.saynotobugs.confidence.rxjava3.RxSubjectAdapter;
-
 import io.reactivex.rxjava3.subjects.SingleSubject;
+import org.saynotobugs.confidence.rxjava3.RxSubjectAdapter;
 
 
 /**
@@ -52,10 +51,15 @@ public void onComplete()
         throw new UnsupportedOperationException("SingleSubjectAdapter.onComplete() called, but Singles require a value");
     }
 
-
     @Override
     public void onError(Throwable error)
     {
         mDelegate.onError(error);
     }
+
+    @Override
+    public boolean hasSubscribers()
+    {
+        return mDelegate.hasObservers();
+    }
 }

confidence-rxjava3/src/main/java/org/saynotobugs/confidence/rxjava3/procedure/HasSubscribers.java

@@ -0,0 +1,36 @@
+/*
+ * Copyright 2022 dmfs GmbH
+ *
+ *
+ * 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 org.saynotobugs.confidence.rxjava3.procedure;
+
+import org.dmfs.srcless.annotations.staticfactory.StaticFactories;
+import org.saynotobugs.confidence.description.Text;
+import org.saynotobugs.confidence.quality.composite.QualityComposition;
+import org.saynotobugs.confidence.quality.object.Satisfies;
+import org.saynotobugs.confidence.rxjava3.RxSubjectAdapter;
+
+
+@StaticFactories(value = "RxJava3", packageName = "org.saynotobugs.confidence.rxjava3")
+public final class HasSubscribers extends QualityComposition<RxSubjectAdapter<?>>
+{
+    public HasSubscribers()
+    {
+        super(new Satisfies<>(RxSubjectAdapter::hasSubscribers, __ -> new Text("had no subscribers"), new Text("has subscribers")));
+    }
+
+}

confidence-rxjava3/src/main/java/org/saynotobugs/confidence/rxjava3/rxexpectation/Disposal.java

@@ -0,0 +1,39 @@
+/*
+ * Copyright 2022 dmfs GmbH
+ *
+ *
+ * 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 org.saynotobugs.confidence.rxjava3.rxexpectation;
+
+import org.dmfs.srcless.annotations.staticfactory.StaticFactories;
+import org.saynotobugs.confidence.description.Text;
+import org.saynotobugs.confidence.quality.object.Successfully;
+import org.saynotobugs.confidence.rxjava3.RxExpectation;
+import org.saynotobugs.confidence.rxjava3.RxExpectationComposition;
+import org.saynotobugs.confidence.rxjava3.RxTestAdapter;
+
+
+@StaticFactories(value = "RxJava3", packageName = "org.saynotobugs.confidence.rxjava3")
+public final class Disposal<T> extends RxExpectationComposition<T>
+{
+    /**
+     * Creates an {@link RxExpectation} that disposes the subscription.
+     */
+    public Disposal()
+    {
+        super(testScheduFler -> new Successfully<>(new Text("disposal"), new Text("disposal"), RxTestAdapter::cancel));
+    }
+}

confidence-rxjava3/src/test/java/org/saynotobugs/confidence/rxjava3/Examples.java

@@ -1,17 +1,17 @@
 package org.saynotobugs.confidence.rxjava3;
 
+import io.reactivex.rxjava3.core.*;
+import io.reactivex.rxjava3.schedulers.TestScheduler;
 import org.junit.jupiter.api.Test;
 
 import java.io.IOException;
 import java.util.concurrent.atomic.AtomicInteger;
 
-import io.reactivex.rxjava3.core.*;
-import io.reactivex.rxjava3.schedulers.TestScheduler;
-
 import static java.time.Duration.ofSeconds;
 import static java.util.concurrent.TimeUnit.SECONDS;
 import static org.saynotobugs.confidence.Assertion.assertThat;
 import static org.saynotobugs.confidence.quality.Core.*;
+import static org.saynotobugs.confidence.rxjava3.RxJava3.when;
 import static org.saynotobugs.confidence.rxjava3.RxJava3.*;
 
 
@@ -191,4 +191,17 @@ void testCompletableTransformer()
                     downstream(immediately(errors(IOException.class))))));
     }
 
+
+    @Test
+    void testCancelledFlowableTransformer()
+    {
+        assertThat((Flowable<Integer> upstream) -> upstream,
+            unscheduled(transformsFlowable(
+                upstream(emit(1, 2, 3)),
+                downstream(emits(1, 2, 3)),
+                downstream(disposal()),
+                upstream(not(hasSubscribers()))
+            )));
+    }
+
 }

confidence-rxjava3/src/test/java/org/saynotobugs/confidence/rxjava3/adapters/RxTestObserverTest.java

@@ -0,0 +1,59 @@
+/*
+ * Copyright 2023 dmfs GmbH
+ *
+ *
+ * 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 org.saynotobugs.confidence.rxjava3.adapters;
+
+import io.reactivex.rxjava3.subjects.PublishSubject;
+import org.junit.jupiter.api.Test;
+import org.saynotobugs.confidence.description.Text;
+import org.saynotobugs.confidence.quality.composite.AllOf;
+import org.saynotobugs.confidence.quality.composite.Not;
+import org.saynotobugs.confidence.quality.function.MutatesArgument;
+import org.saynotobugs.confidence.quality.grammar.SoIt;
+import org.saynotobugs.confidence.quality.grammar.When;
+import org.saynotobugs.confidence.quality.object.Satisfies;
+import org.saynotobugs.confidence.quality.object.Successfully;
+import org.saynotobugs.confidence.quality.trivial.Anything;
+
+import static org.saynotobugs.confidence.Assertion.assertThat;
+
+class RxTestObserverTest
+{
+    @Test
+    void testDispose()
+    {
+        assertThat((PublishSubject<Object> observable) -> {
+                RxTestObserver<Object> testObserver = new RxTestObserver<>();
+                observable.subscribeWith(testObserver);
+                return testObserver;
+            },
+            new AllOf<>(
+                // first assert the function above actually subscribes
+                new MutatesArgument<>(
+                    PublishSubject::create,
+                    new SoIt<>(new Satisfies<>(PublishSubject::hasObservers, new Text("hasObserver"))),
+                    new When<>(new Anything())),
+                new MutatesArgument<>(
+                    PublishSubject::create,
+                    new SoIt<>(new Not<>(new Satisfies<>(PublishSubject::hasObservers, new Text("hasObserver")))),
+                    new When<>(new Successfully<>(new Text("Cancelled"), new Text("Cancelled"), (RxTestObserver<Object> o) -> o.cancel()))
+                ))
+        );
+    }
+
+}