Merge pull request #15748 from cvienot

* pr/15748:
  Polish "Alias auto-configured `TaskExecutor` to make async tasks use it"
  Alias auto-configured `TaskExecutor` to make async tasks use it

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/task/TaskExecutionAutoConfiguration.java

 /*
- * Copyright 2012-2018 the original author or authors.
+ * Copyright 2012-2019 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -30,12 +30,14 @@ import org.springframework.context.annotation.Configuration;
 import org.springframework.context.annotation.Lazy;
 import org.springframework.core.task.TaskDecorator;
 import org.springframework.core.task.TaskExecutor;
+import org.springframework.scheduling.annotation.AsyncAnnotationBeanPostProcessor;
 import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;
 
 /**
  * {@link EnableAutoConfiguration Auto-configuration} for {@link TaskExecutor}.
  *
  * @author Stephane Nicoll
+ * @author Camille Vienot
  * @since 2.1.0
  */
 @ConditionalOnClass(ThreadPoolTaskExecutor.class)
@@ -79,7 +81,8 @@ public class TaskExecutionAutoConfiguration {
 	}
 
 	@Lazy
-	@Bean(name = APPLICATION_TASK_EXECUTOR_BEAN_NAME)
+	@Bean(name = { APPLICATION_TASK_EXECUTOR_BEAN_NAME,
+			AsyncAnnotationBeanPostProcessor.DEFAULT_TASK_EXECUTOR_BEAN_NAME })
 	@ConditionalOnMissingBean(Executor.class)
 	public ThreadPoolTaskExecutor applicationTaskExecutor(TaskExecutorBuilder builder) {
 		return builder.build();

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/task/TaskExecutionAutoConfigurationTests.java

 /*
- * Copyright 2012-2018 the original author or authors.
+ * Copyright 2012-2019 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -38,6 +38,7 @@ import org.springframework.core.task.TaskExecutor;
 import org.springframework.scheduling.annotation.Async;
 import org.springframework.scheduling.annotation.AsyncResult;
 import org.springframework.scheduling.annotation.EnableAsync;
+import org.springframework.scheduling.annotation.EnableScheduling;
 import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;
 import org.springframework.test.util.ReflectionTestUtils;
 
@@ -49,6 +50,7 @@ import static org.mockito.Mockito.verify;
  * Tests for {@link TaskExecutionAutoConfiguration}.
  *
  * @author Stephane Nicoll
+ * @author Camille Vienot
  */
 public class TaskExecutionAutoConfigurationTests {
 
@@ -152,6 +154,21 @@ public class TaskExecutionAutoConfigurationTests {
 				});
 	}
 
+	@Test
+	public void enableAsyncUsesAutoConfiguredOneByDefaultEvenThoughSchedulingIsConfigured() {
+		this.contextRunner
+				.withPropertyValues("spring.task.execution.thread-name-prefix=task-test-")
+				.withConfiguration(
+						AutoConfigurations.of(TaskSchedulingAutoConfiguration.class))
+				.withUserConfiguration(AsyncConfiguration.class,
+						SchedulingConfiguration.class, TestBean.class)
+				.run((context) -> {
+					TestBean bean = context.getBean(TestBean.class);
+					String text = bean.echo("something").get();
+					assertThat(text).contains("task-test-").contains("something");
+				});
+	}
+
 	private ContextConsumer<AssertableApplicationContext> assertTaskExecutor(
 			Consumer<ThreadPoolTaskExecutor> taskExecutor) {
 		return (context) -> {
@@ -209,6 +226,12 @@ public class TaskExecutionAutoConfigurationTests {
 
 	}
 
+	@Configuration
+	@EnableScheduling
+	static class SchedulingConfiguration {
+
+	}
+
 	static class TestBean {
 
 		@Async