Add test slice for Spring Data R2DBC

This commit adds a test slice for Spring Data R2DBC. When
`DataR2dbcTest` is added on a test, only Spring Data R2DBC repositories
and the infrastructure that they need is auto-configured.

Contrary to the JDBC counterpart, the `ConnectionFactory` is not swapped
by an embedded database.

See gh-19988

Co-authored-by: Mark Paluch <mpaluch@pivotal.io>

spring-boot-project/spring-boot-test-autoconfigure/src/test/java/org/springframework/boot/test/autoconfigure/data/r2dbc/DataR2dbcTestIntegrationTests.java

@@ -0,0 +1,80 @@
+/*
+ * Copyright 2012-2020 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
+ *
+ *      https://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.boot.test.autoconfigure.data.r2dbc;
+
+import io.r2dbc.spi.ConnectionFactory;
+import org.junit.jupiter.api.Test;
+import reactor.test.StepVerifier;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.TestConfiguration;
+import org.springframework.context.ApplicationContext;
+import org.springframework.core.io.DefaultResourceLoader;
+import org.springframework.core.io.Resource;
+import org.springframework.core.io.ResourceLoader;
+import org.springframework.data.r2dbc.connectionfactory.init.ResourceDatabasePopulator;
+import org.springframework.data.r2dbc.core.DatabaseClient;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Integration tests for {@link DataR2dbcTest}.
+ *
+ * @author Mark Paluch
+ */
+@DataR2dbcTest
+class DataR2dbcTestIntegrationTests {
+
+	@Autowired
+	private DatabaseClient databaseClient;
+
+	@Autowired
+	private ConnectionFactory connectionFactory;
+
+	@Autowired
+	private ApplicationContext applicationContext;
+
+	@Test
+	void testDatabaseClient() {
+		this.databaseClient.execute("SELECT * FROM example").fetch().all().as(StepVerifier::create).verifyComplete();
+	}
+
+	@Test
+	void replacesDefinedConnectionFactoryWithEmbeddedDefault() {
+		String product = this.connectionFactory.getMetadata().getName();
+		assertThat(product).isEqualTo("H2");
+	}
+
+	@Test
+	void registersExampleRepository() {
+		assertThat(this.applicationContext.getBeanNamesForType(ExampleRepository.class)).isNotEmpty();
+	}
+
+	@TestConfiguration
+	static class DatabaseInitializationConfiguration {
+
+		@Autowired
+		void initializeDatabase(ConnectionFactory connectionFactory) {
+			ResourceLoader resourceLoader = new DefaultResourceLoader();
+			Resource[] scripts = new Resource[] { resourceLoader
+					.getResource("classpath:org/springframework/boot/test/autoconfigure/data/r2dbc/schema.sql") };
+			new ResourceDatabasePopulator(scripts).execute(connectionFactory).block();
+		}
+
+	}
+
+}

spring-boot-project/spring-boot-test-autoconfigure/src/test/java/org/springframework/boot/test/autoconfigure/data/r2dbc/DataR2dbcTestPropertiesIntegrationTests.java

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+/*
+ * Copyright 2012-2020 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
+ *
+ *      https://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.boot.test.autoconfigure.data.r2dbc;
+
+import org.junit.jupiter.api.Test;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.core.env.Environment;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Tests for the {@link DataR2dbcTest#properties properties} attribute of
+ * {@link DataR2dbcTest @DataR2dbcTest}.
+ *
+ * @author Mark Paluch
+ */
+@DataR2dbcTest(properties = "spring.profiles.active=test")
+class DataR2dbcTestPropertiesIntegrationTests {
+
+	@Autowired
+	private Environment environment;
+
+	@Test
+	void environmentWithNewProfile() {
+		assertThat(this.environment.getActiveProfiles()).containsExactly("test");
+	}
+
+}

spring-boot-project/spring-boot-test-autoconfigure/src/test/java/org/springframework/boot/test/autoconfigure/data/r2dbc/Example.java

@@ -0,0 +1,33 @@
+/*
+ * Copyright 2012-2020 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
+ *
+ *      https://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.boot.test.autoconfigure.data.r2dbc;
+
+import org.springframework.data.annotation.Id;
+import org.springframework.data.relational.core.mapping.Table;
+
+/**
+ * Example entity used with {@link DataR2dbcTest} tests.
+ *
+ * @author Mark Paluch
+ */
+@Table
+public class Example {
+
+	@Id
+	String id;
+
+}

spring-boot-project/spring-boot-test-autoconfigure/src/test/java/org/springframework/boot/test/autoconfigure/data/r2dbc/ExampleR2dbcApplication.java

@@ -0,0 +1,29 @@
+/*
+ * Copyright 2012-2020 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
+ *
+ *      https://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.boot.test.autoconfigure.data.r2dbc;
+
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+/**
+ * Example {@link SpringBootApplication} used with {@link DataR2dbcTest} tests.
+ *
+ * @author Mark Paluch
+ */
+@SpringBootApplication
+public class ExampleR2dbcApplication {
+
+}

spring-boot-project/spring-boot-test-autoconfigure/src/test/java/org/springframework/boot/test/autoconfigure/data/r2dbc/ExampleRepository.java

@@ -0,0 +1,28 @@
+/*
+ * Copyright 2012-2020 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
+ *
+ *      https://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.boot.test.autoconfigure.data.r2dbc;
+
+import org.springframework.data.repository.reactive.ReactiveCrudRepository;
+
+/**
+ * Example {@link ReactiveCrudRepository} used with {@link DataR2dbcTest} tests.
+ *
+ * @author Mark Paluch
+ */
+public interface ExampleRepository extends ReactiveCrudRepository<Example, String> {
+
+}

spring-boot-project/spring-boot-test-autoconfigure/src/test/resources/org/springframework/boot/test/autoconfigure/data/r2dbc/schema.sql

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+drop table if exists example;
+create table example (id int, name varchar);