junit-jupiter-api/src/main/java/org/junit/jupiter/api/AssertAll.java

/*
 * Copyright 2015-2022 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.api;

import java.util.Arrays;
import java.util.Collection;
import java.util.List;
import java.util.Objects;
import java.util.stream.Collectors;
import java.util.stream.Stream;

import org.junit.jupiter.api.function.Executable;
import org.junit.platform.commons.util.Preconditions;
import org.junit.platform.commons.util.UnrecoverableExceptions;
import org.opentest4j.MultipleFailuresError;

/**
 * {@code AssertAll} is a collection of utility methods that support asserting
 * multiple conditions in tests at once.
 *
 * @since 5.0
 */
class AssertAll {

	private AssertAll() {
		/* no-op */
	}

	static void assertAll(Executable... executables) {
		assertAll(null, executables);
	}

	static void assertAll(String heading, Executable... executables) {
		Preconditions.notEmpty(executables, "executables array must not be null or empty");
		Preconditions.containsNoNullElements(executables, "individual executables must not be null");
		assertAll(heading, Arrays.stream(executables));
	}

	static void assertAll(Collection<Executable> executables) {
		assertAll(null, executables);
	}

	static void assertAll(String heading, Collection<Executable> executables) {
		Preconditions.notNull(executables, "executables collection must not be null");
		Preconditions.containsNoNullElements(executables, "individual executables must not be null");
		assertAll(heading, executables.stream());
	}

	static void assertAll(Stream<Executable> executables) {
		assertAll(null, executables);
	}

	static void assertAll(String heading, Stream<Executable> executables) {
		Preconditions.notNull(executables, "executables stream must not be null");

		List<Throwable> failures = executables //
				.map(executable -> {
					Preconditions.notNull(executable, "individual executables must not be null");
					try {
						executable.execute();
						return null;
					}
					catch (Throwable t) {
						UnrecoverableExceptions.rethrowIfUnrecoverable(t);
						return t;
					}
				}) //
				.filter(Objects::nonNull) //
				.collect(Collectors.toList());

		if (!failures.isEmpty()) {
			MultipleFailuresError multipleFailuresError = new MultipleFailuresError(heading, failures);
			failures.forEach(multipleFailuresError::addSuppressed);
			throw multipleFailuresError;
		}
	}

}