content: /*
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements.  See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership.  The ASF licenses this file
   * to you 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.apache.aries.async.promise.test;
  
  import static org.junit.Assert.assertEquals;
  import static org.junit.Assert.assertFalse;
  import static org.junit.Assert.assertNotNull;
  import static org.junit.Assert.assertNull;
  import static org.junit.Assert.assertTrue;
  import static org.junit.Assert.fail;
  
  import java.lang.reflect.InvocationTargetException;
  
  import org.junit.Test;
  import org.osgi.util.promise.Deferred;
  import org.osgi.util.promise.Promise;
  
  public class DeferredTest {
  
      @Test
      public void testResolve() throws Exception {
          Deferred<String> def = new Deferred<String>();
          Promise<String> promise = def.getPromise();
          assertFalse("Initial Promise not resolved", promise.isDone());
  
          def.resolve("Hello");
          assertTrue("Promise resolved", promise.isDone());
          assertEquals("Value matches", "Hello", promise.getValue());
          assertNull("Failure is null", promise.getFailure());
  
          try {
              def.resolve("Again");
              fail("Already resolved didn't throw IllegalStateException");
          } catch (IllegalStateException e) {
              // suppress empty catch block warning
          }
      }
  
      @Test
      public void testResolveWithSuccess() throws Exception {
          Deferred<String> def = new Deferred<String>();
          Promise<String> promise = def.getPromise();
  
          Deferred<String> with = new Deferred<String>();
          Promise<Void> resolvedWith = def.resolveWith(with.getPromise());
  
          // If the specified Promise is successfully resolved,
          // the associated Promise is resolved with the value of the specified Promise.
          with.resolve("resolveWith");
          assertTrue("Promise resolved", promise.isDone());
          assertEquals("Value matches", "resolveWith", promise.getValue());
  
          // The returned Promise will be successfully resolved, with the value null,
          // if the associated Promise was resolved by the specified Promise.
          assertNull("resolveWith null", resolvedWith.getValue());
      }
  
      @Test
      public void testResolveWithAlreadyResolved() throws Exception {
          Deferred<String> def = new Deferred<String>();
          Deferred<String> with = new Deferred<String>();
          Promise<Void> resolvedWith = def.resolveWith(with.getPromise());
  
          // The returned Promise will be resolved with a failure of IllegalStateException
          // if the associated Promise was already resolved when the specified Promise was resolved.
          def.resolve("Already resolved");
          with.resolve("resolveWith");
          @SuppressWarnings({"not thrown", "all"})
          Throwable failure = resolvedWith.getFailure();
          assertTrue("resolveWith IllegalStateException", failure instanceof IllegalStateException);
      }
  
      @Test
      public void testResolveWithAlreadyFailed() throws Exception {
          Deferred<String> def = new Deferred<String>();
          Deferred<String> with = new Deferred<String>();
          Promise<Void> resolvedWith = def.resolveWith(with.getPromise());
  
          // The returned Promise will be resolved with a failure of IllegalStateException
          // if the associated Promise was already resolved when the specified Promise was resolved.
          def.resolve("Already resolved");
          with.fail(new Throwable("failed"));
          @SuppressWarnings({"not thrown", "all"})
          Throwable failure = resolvedWith.getFailure();
          assertTrue("resolveWith IllegalStateException", failure instanceof IllegalStateException);
      }
  
      @Test
      public void testResolveWithFailure() throws Exception {
          Deferred<String> def = new Deferred<String>();
          Promise<String> promise = def.getPromise();
  
          Deferred<String> def2 = new Deferred<String>();
          Promise<String> promise2 = def2.getPromise();
          Promise<Void> with = def.resolveWith(promise2);
  
          // If the specified Promise is resolved with a failure,
          // the associated Promise is resolved with the failure of the specified Promise.
          Exception failure = new Exception("resolveWithFailure");
          def2.fail(failure);
          assertTrue("Promise resolved", promise.isDone());
          assertEquals("Failure matches", failure, promise.getFailure());
  
          // The returned Promise will be successfully resolved, with the value null,
          // if the associated Promise was resolved by the specified Promise.
          assertNull("resolveWith null", with.getValue());
      }
  
      @Test
      public void testFail() throws Exception {
          Deferred<String> def = new Deferred<String>();
          Promise<String> promise = def.getPromise();
          Exception failure = new Exception("Oops");
  
          def.fail(failure);
          assertTrue("Promise resolved", promise.isDone());
          assertEquals("Failure matches", failure, promise.getFailure());
  
          try {
              promise.getValue();
              fail("getValue didn't throw InvocationTargetException");
          } catch (InvocationTargetException e) {
              assertEquals("Failure matches", failure, e.getCause());
          }
  
          try {
              def.fail(failure);
              fail("Already failed didn't throw IllegalStateException");
          } catch (IllegalStateException e) {
              assertNotNull(e);
          }
      }
  
  
  }
  