Ensure FunctionalSpringApplication works with String sources

spring-cloud-function-context/src/test/java/org/springframework/cloud/function/context/string/FunctionalStringSourceTests.java

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+/*
+ * Copyright 2018 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.
+ * 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.springframework.cloud.function.context.string;
+
+import java.util.function.Function;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.cloud.function.context.FunctionCatalog;
+import org.springframework.cloud.function.context.test.FunctionalSpringBootTest;
+import org.springframework.test.context.junit4.SpringRunner;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import reactor.core.publisher.Flux;
+
+/**
+ * Test that spring.main.sources works with the functional approach.
+ * 
+ * @author Dave Syer
+ *
+ */
+@RunWith(SpringRunner.class)
+@FunctionalSpringBootTest(classes = Object.class, properties = "spring.main.sources=org.springframework.cloud.function.context.string.FunctionalStringSourceTests.TestConfiguration")
+public class FunctionalStringSourceTests {
+
+	@Autowired
+	private FunctionCatalog catalog;
+
+	@Test
+	public void words() throws Exception {
+		Function<Flux<String>, Flux<String>> function = catalog.lookup(Function.class,
+				"function");
+		assertThat(function.apply(Flux.just("foo")).blockFirst()).isEqualTo("FOO");
+	}
+
+	protected static class TestConfiguration implements Function<String, String> {
+		@Override
+		public String apply(String value) {
+			return value.toUpperCase();
+		}
+	}
+}