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/*
* Copyright 2015-2021 the original author or authors.
*
* All rights reserved. This program and the accompanying materials are
* made available under the terms of the Eclipse Public License v2.0 which
* accompanies this distribution and is available at
*
* https://www.eclipse.org/legal/epl-v20.html
*/
package org.junit.jupiter.engine.descriptor;
import static java.util.stream.Collectors.toList;
import static org.junit.platform.commons.util.AnnotationUtils.findAnnotation;
import static org.junit.platform.commons.util.AnnotationUtils.findRepeatableAnnotations;
import static org.junit.platform.commons.util.AnnotationUtils.isAnnotated;
import static org.junit.platform.commons.util.ReflectionUtils.HierarchyTraversalMode.TOP_DOWN;
import static org.junit.platform.commons.util.ReflectionUtils.findFields;
import static org.junit.platform.commons.util.ReflectionUtils.getDeclaredConstructor;
import static org.junit.platform.commons.util.ReflectionUtils.tryToReadFieldValue;
import java.lang.reflect.AnnotatedElement;
import java.lang.reflect.Executable;
import java.lang.reflect.Field;
import java.util.Arrays;
import java.util.Comparator;
import java.util.List;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.function.Predicate;
import java.util.stream.Stream;
import org.junit.jupiter.api.Order;
import org.junit.jupiter.api.extension.ExtendWith;
import org.junit.jupiter.api.extension.Extension;
import org.junit.jupiter.api.extension.RegisterExtension;
import org.junit.jupiter.engine.extension.ExtensionRegistrar;
import org.junit.jupiter.engine.extension.MutableExtensionRegistry;
import org.junit.platform.commons.util.Preconditions;
import org.junit.platform.commons.util.ReflectionUtils;
/**
* Collection of utilities for working with extensions and the extension registry.
*
* @since 5.1
* @see ExtensionRegistrar
* @see MutableExtensionRegistry
* @see ExtendWith
* @see RegisterExtension
*/
final class ExtensionUtils {
private ExtensionUtils() {
/* no-op */
}
/**
* Populate a new {@link MutableExtensionRegistry} from extension types declared via
* {@link ExtendWith @ExtendWith} on the supplied {@link AnnotatedElement}.
*
* @param parentRegistry the parent extension registry to set in the newly
* created registry; never {@code null}
* @param annotatedElement the annotated element on which to search for
* declarations of {@code @ExtendWith}; never {@code null}
*
* @return the new extension registry; never {@code null}
* @since 5.0
*/
static MutableExtensionRegistry populateNewExtensionRegistryFromExtendWithAnnotation(
MutableExtensionRegistry parentRegistry, AnnotatedElement annotatedElement) {
Preconditions.notNull(parentRegistry, "Parent ExtensionRegistry must not be null");
Preconditions.notNull(annotatedElement, "AnnotatedElement must not be null");
return MutableExtensionRegistry.createRegistryFrom(parentRegistry, streamExtensionTypes(annotatedElement));
}
/**
* Register extensions using the supplied registrar from fields in the supplied
* class that are annotated with {@link ExtendWith @ExtendWith} or
* {@link RegisterExtension @RegisterExtension}.
*
* The extensions will be sorted according to {@link Order @Order} semantics
* prior to registration.
*
* @param registrar the registrar with which to register the extensions; never {@code null}
* @param clazz the class or interface in which to find the fields; never {@code null}
* @param instance the instance of the supplied class; may be {@code null}
* when searching for {@code static} fields in the class
*/
static void registerExtensionsFromFields(ExtensionRegistrar registrar, Class clazz, Object instance) {
Preconditions.notNull(registrar, "ExtensionRegistrar must not be null");
Preconditions.notNull(clazz, "Class must not be null");
Predicate predicate = (instance == null ? ReflectionUtils::isStatic : ReflectionUtils::isNotStatic);
findFields(clazz, predicate, TOP_DOWN).stream()//
.sorted(orderComparator)//
.forEach(field -> {
List> extensionTypes = streamExtensionTypes(field).collect(toList());
boolean isExtendWithPresent = !extensionTypes.isEmpty();
boolean isRegisterExtensionPresent = isAnnotated(field, RegisterExtension.class);
if (isExtendWithPresent) {
extensionTypes.forEach(registrar::registerExtension);
}
if (isRegisterExtensionPresent) {
tryToReadFieldValue(field, instance).ifSuccess(value -> {
Preconditions.condition(value instanceof Extension, () -> String.format(
"Failed to register extension via @RegisterExtension field [%s]: field value's type [%s] must implement an [%s] API.",
field, (value != null ? value.getClass().getName() : null), Extension.class.getName()));
if (isExtendWithPresent) {
Class valueType = value.getClass();
extensionTypes.forEach(extensionType -> {
Preconditions.condition(!extensionType.equals(valueType),
() -> String.format("Failed to register extension via field [%s]. "
+ "The field registers an extension of type [%s] via @RegisterExtension and @ExtendWith, "
+ "but only one registration of a given extension type is permitted.",
field, valueType.getName()));
});
}
registrar.registerExtension((Extension) value, field);
});
}
});
}
/**
* Register extensions using the supplied registrar from parameters in the
* declared constructor of the supplied class that are annotated with
* {@link ExtendWith @ExtendWith}.
*
* @param registrar the registrar with which to register the extensions; never {@code null}
* @param clazz the class in which to find the declared constructor; never {@code null}
* @since 5.8
*/
static void registerExtensionsFromConstructorParameters(ExtensionRegistrar registrar, Class clazz) {
registerExtensionsFromExecutableParameters(registrar, getDeclaredConstructor(clazz));
}
/**
* Register extensions using the supplied registrar from parameters in the
* supplied {@link Executable} (i.e., a {@link java.lang.reflect.Constructor}
* or {@link java.lang.reflect.Method}) that are annotated with
* {@link ExtendWith @ExtendWith}.
*
* @param registrar the registrar with which to register the extensions; never {@code null}
* @param executable the constructor or method whose parameters should be searched; never {@code null}
* @since 5.8
*/
static void registerExtensionsFromExecutableParameters(ExtensionRegistrar registrar, Executable executable) {
Preconditions.notNull(registrar, "ExtensionRegistrar must not be null");
Preconditions.notNull(executable, "Executable must not be null");
AtomicInteger index = new AtomicInteger();
// @formatter:off
Arrays.stream(executable.getParameters())
.map(parameter -> findRepeatableAnnotations(parameter, index.getAndIncrement(), ExtendWith.class))
.flatMap(ExtensionUtils::streamExtensionTypes)
.forEach(registrar::registerExtension);
// @formatter:on
}
/**
* @since 5.8
*/
private static Stream> streamExtensionTypes(AnnotatedElement annotatedElement) {
return streamExtensionTypes(findRepeatableAnnotations(annotatedElement, ExtendWith.class));
}
/**
* @since 5.8
*/
private static Stream> streamExtensionTypes(List extendWithAnnotations) {
return extendWithAnnotations.stream().map(ExtendWith::value).flatMap(Arrays::stream);
}
/**
* @since 5.4
*/
private static final Comparator orderComparator = //
Comparator.comparingInt(ExtensionUtils::getOrder);
/**
* @since 5.4
*/
private static int getOrder(Field field) {
return findAnnotation(field, Order.class).map(Order::value).orElse(Order.DEFAULT);
}
}