Document auto-configuration classes imported by each @…Test annotation

Closes gh-6044

spring-boot-docs/pom.xml

@@ -886,6 +886,25 @@
 									</artifactItems>
 								</configuration>
 							</execution>
+							<execution>
+								<id>unpack-test-slices</id>
+								<phase>generate-resources</phase>
+								<goals>
+									<goal>unpack</goal>
+								</goals>
+								<configuration>
+									<artifactItems>
+										<artifactItem>
+											<groupId>org.springframework.boot</groupId>
+											<artifactId>spring-boot-test-autoconfigure</artifactId>
+											<version>${project.version}</version>
+											<outputDirectory>
+												${project.build.directory}/test-auto-config
+											</outputDirectory>
+										</artifactItem>
+									</artifactItems>
+								</configuration>
+							</execution>
 						</executions>
 					</plugin>
 					<plugin>
@@ -932,6 +951,7 @@
 							<scripts>
 								<script>file:///${project.basedir}/src/main/groovy/generateAutoConfigurationClassTables.groovy</script>
 								<script>file:///${project.basedir}/src/main/groovy/generateStarterTables.groovy</script>
+								<script>file:///${project.basedir}/src/main/groovy/generateTestSlicesTable.groovy</script>
 							</scripts>
 						</configuration>
 						<dependencies>
@@ -940,6 +960,11 @@
 								<artifactId>groovy-all</artifactId>
 								<version>${groovy.version}</version>
 							</dependency>
+							<dependency>
+								<groupId>org.springframework</groupId>
+								<artifactId>spring-core</artifactId>
+								<version>${spring.version}</version>
+							</dependency>
 						</dependencies>
 					</plugin>
 					<plugin>

spring-boot-docs/src/main/asciidoc/appendix-test-auto-configuration.adoc

@@ -0,0 +1,7 @@
+[appendix]
+[[test-auto-configuration]]
+== Test auto-configuration annotations
+Here is a table of the various `@…Test` annotations that can be used to test
+slices of your application and the auto-configuration that they import by default:
+
+include::../../../target/generated-resources/test-slice-auto-configuration.adoc[]

spring-boot-docs/src/main/asciidoc/appendix.adoc

@@ -4,5 +4,6 @@
 include::appendix-application-properties.adoc[]
 include::appendix-configuration-metadata.adoc[]
 include::appendix-auto-configuration-classes.adoc[]
+include::appendix-test-auto-configuration.adoc[]
 include::appendix-executable-jar-format.adoc[]
 include::appendix-dependency-versions.adoc[]

spring-boot-docs/src/main/asciidoc/spring-boot-features.adoc

@@ -4879,6 +4879,9 @@ NOTE: JSON helper classes can also be used directly in standard unit tests. Simp
 call the `initFields` method of the helper in your `@Before` method if you aren't using
 `@JsonTest`.
 
+A list of the auto-configuration that is enabled by `@JsonTest` can be
+<<appendix-test-auto-configuration#test-auto-configuration,found in the appendix>>.
+
 
 
 [[boot-features-testing-spring-boot-applications-testing-autoconfigured-mvc-tests]]
@@ -4971,6 +4974,9 @@ and/or a `WebDriver` bean. Here is an example that uses HtmlUnit:
 	}
 ----
 
+A list of the auto-configuration that is enabled by `@WebMvcTest` can be
+<<appendix-test-auto-configuration#test-auto-configuration,found in the appendix>>.
+
 
 
 [[boot-features-testing-spring-boot-applications-testing-autoconfigured-jpa-test]]
@@ -5053,6 +5059,8 @@ database you can use the `@AutoConfigureTestDatabase` annotation:
 	}
 ----
 
+A list of the auto-configuration that is enabled by `@DataJpaTest` can be
+<<appendix-test-auto-configuration#test-auto-configuration,found in the appendix>>.
 
 
 
@@ -5088,6 +5096,9 @@ be specified using `value` or `components` attribute of `@RestClientTest`:
 	}
 ----
 
+A list of the auto-configuration that is enabled by `@RestClientTest` can be
+<<appendix-test-auto-configuration#test-auto-configuration,found in the appendix>>.
+
 
 
 [[boot-features-testing-spring-boot-applications-testing-autoconfigured-rest-docs]]

spring-boot-docs/src/main/groovy/generateTestSlicesTable.groovy

@@ -0,0 +1,109 @@
+import groovy.io.FileType
+
+import java.util.Properties
+
+import org.springframework.core.io.InputStreamResource
+import org.springframework.core.io.Resource
+import org.springframework.core.type.AnnotationMetadata
+import org.springframework.core.type.ClassMetadata
+import org.springframework.core.type.classreading.MetadataReader
+import org.springframework.core.type.classreading.MetadataReaderFactory
+import org.springframework.core.type.classreading.SimpleMetadataReaderFactory
+import org.springframework.util.ClassUtils
+import org.springframework.util.StringUtils
+
+class Project {
+
+	final List<File> classFiles
+
+	final Properties springFactories
+
+	Project(File rootDirectory) {
+		this.springFactories = loadSpringFactories(rootDirectory)
+		this.classFiles = []
+		rootDirectory.eachFileRecurse (FileType.FILES) { file ->
+			if (file.name.endsWith('.class')) {
+				classFiles << file
+			}
+		}
+	}
+
+	private static Properties loadSpringFactories(File rootDirectory) {
+		Properties springFactories = new Properties()
+		new File(rootDirectory, 'META-INF/spring.factories').withInputStream { inputStream ->
+			springFactories.load(inputStream)
+		}
+		return springFactories
+	}
+}
+
+class TestSlice {
+
+	final String name
+
+	final SortedSet<String> importedAutoConfiguration
+
+	TestSlice(String annotationName, Collection<String> importedAutoConfiguration) {
+		this.name = ClassUtils.getShortName(annotationName)
+		this.importedAutoConfiguration = new TreeSet<String>(importedAutoConfiguration)
+	}
+}
+
+List<TestSlice> createTestSlices(Project project) {
+	MetadataReaderFactory metadataReaderFactory = new SimpleMetadataReaderFactory()
+	project.classFiles
+		.findAll { classFile ->
+			classFile.name.endsWith('Test.class')
+		}.collect { classFile ->
+			createMetadataReader(metadataReaderFactory, classFile)
+		}.findAll { metadataReader ->
+			metadataReader.classMetadata.annotation
+		}.collect { metadataReader ->
+			createTestSlice(project.springFactories, metadataReader.classMetadata, metadataReader.annotationMetadata)
+		}.sort {
+			a, b -> a.name.compareTo b.name
+		}
+}
+
+MetadataReader createMetadataReader(MetadataReaderFactory factory, File classFile) {
+	classFile.withInputStream { inputStream ->
+		factory.getMetadataReader(new InputStreamResource(inputStream))
+	}
+}
+
+TestSlice createTestSlice(Properties springFactories, ClassMetadata classMetadata, AnnotationMetadata annotationMetadata) {
+	new TestSlice(classMetadata.className, getImportedAutoConfiguration(springFactories, classMetadata, annotationMetadata))
+}
+
+Set<String> getImportedAutoConfiguration(Properties springFactories, ClassMetadata classMetadata, AnnotationMetadata annotationMetadata) {
+	annotationMetadata.annotationTypes
+		.findAll { annotationType ->
+			isAutoConfigurationImporter(annotationType, annotationMetadata)
+		}.collect { autoConfigurationImporter ->
+			StringUtils.commaDelimitedListToSet(springFactories.get(autoConfigurationImporter))
+		}.flatten()
+}
+
+boolean isAutoConfigurationImporter(String annotationType, AnnotationMetadata metadata) {
+	metadata.getMetaAnnotationTypes(annotationType).contains('org.springframework.boot.autoconfigure.ImportAutoConfiguration')
+}
+
+void writeTestSlicesTable(List<TestSlice> testSlices) {
+	new File(project.build.directory, "generated-resources/test-slice-auto-configuration.adoc").withPrintWriter { writer ->
+		writer.println '[cols="d,a"]'
+		writer.println '|==='
+		writer.println '| Test slice | Imported auto-configuration'
+		testSlices.each { testSlice ->
+			writer.println ''
+			writer.println "| `@${testSlice.name}`"
+			writer.print '| '
+			testSlice.importedAutoConfiguration.each {
+				writer.println "`${it}`"
+			}
+		}
+		writer.println '|==='
+	}
+}
+
+List<TestSlice> testSlices = createTestSlices(new Project(new File(project.build.directory, 'test-auto-config')))
+writeTestSlicesTable(testSlices)