More tests for auto detect of start class

spring-cloud-function-deployer/src/test/java/org/springframework/cloud/function/deployer/FunctionCreatorConfigurationTests.java

@@ -59,6 +59,21 @@ public abstract class FunctionCreatorConfigurationTests {
 		}
 	}
 
+	@EnableAutoConfiguration
+	@TestPropertySource(properties = {
+			"function.location=app:classpath,file:target/test-classes,file:target/test-classes/app",
+			"function.bean=myDoubler" })
+	public static class SingleFunctionWithAutoMainTests
+			extends FunctionCreatorConfigurationTests {
+
+		@Test
+		public void testDouble() {
+			Function<Flux<Integer>, Flux<Integer>> function = catalog
+					.lookup(Function.class, "function0");
+			assertThat(function.apply(Flux.just(2)).blockFirst()).isEqualTo(4);
+		}
+	}
+
 	@EnableAutoConfiguration
 	@TestPropertySource(properties = { "function.location=app:classpath",
 			"function.bean=org.springframework.cloud.function.test.SpringDoubler" })

spring-cloud-function-deployer/src/test/resources/app/META-INF/MANIFEST.MF

@@ -0,0 +1,14 @@
+Manifest-Version: 1.0
+Implementation-Title: function-file-sample
+Implementation-Version: 1.0.0.M1
+Archiver-Version: Plexus Archiver
+Built-By: dsyer
+Implementation-Vendor-Id: com.example
+Spring-Boot-Version: 1.5.12.RELEASE
+Implementation-Vendor: Pivotal Software, Inc.
+Main-Class: org.springframework.boot.loader.JarLauncher
+Start-Class: org.springframework.cloud.function.test.FunctionApp
+Created-By: Apache Maven 3.5.0
+Build-Jdk: 1.8.0_131
+Implementation-URL: http://projects.spring.io/spring-boot/function-sam
+ ple/