* requireNonNull(top.next())`) once our checker supports it.
             *
             * (The problem is likely
             * https://github.com/jspecify/jspecify-reference-checker/blob/61aafa4ae52594830cfc2d61c8b113009dbdb045/src/main/java/com/google/jspecify/nullness/NullSpecAnnotatedTypeFactory.java#L896)
             */
            requireNonNull(element);
            if (visited.add(element)) {
              return element;

      <groupId>com.google.guava</groupId>
      <artifactId>listenablefuture</artifactId>
      <version>${listenablefuture.version}</version>
    </dependency>
    <dependency>
      <groupId>org.jspecify</groupId>
      <artifactId>jspecify</artifactId>
    </dependency>
    <dependency>
      <groupId>com.google.errorprone</groupId>
      <artifactId>error_prone_annotations</artifactId>
    </dependency>
    <dependency>

import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
import java.util.concurrent.atomic.AtomicBoolean;
import org.jspecify.annotations.Nullable;

/**
 * An implementation of {@link GraphConnections} for directed graphs.
 *
 * @author James Sexton
 * @author Jens Nyman
 * @param <N> Node parameter type

                        dependencies {
                            "implementation"(gradleApi())
                            "implementation"(kotlin("stdlib"))
                            // TODO remove once JSpecify is part of the Gradle API
                            "implementation"("org.jspecify:jspecify:1.0.0")
                        }
                    }
                    project(":v1") {

import com.google.common.annotations.J2ktIncompatible;
import com.google.common.annotations.VisibleForTesting;
import java.util.AbstractMap;
import java.util.Arrays;
import java.util.Map.Entry;
import org.jspecify.annotations.Nullable;

/**
 * A hash-based implementation of {@link ImmutableMap}.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
final class RegularImmutableMap<K, V> extends ImmutableMap<K, V> {

  </properties>
  <dependencyManagement>
    <dependencies>
      <dependency>
        <groupId>org.jspecify</groupId>
        <artifactId>jspecify</artifactId>
        <version>${jspecify.version}</version>
      </dependency>
      <dependency>
        <groupId>com.google.errorprone</groupId>
        <artifactId>error_prone_annotations</artifactId>

import com.google.common.testing.NullPointerTester;
import java.util.Collections;
import java.util.List;
import java.util.Set;
import junit.framework.TestCase;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * Unit test for {@link Optional}.
 *
 * @author Kurt Alfred Kluever
 */
@NullMarked
@GwtCompatible
public final class OptionalTest extends TestCase {

    private static final List<String> NULLABLE_ANNOTATIONS = [
        javax.annotation.Nullable,
        org.jetbrains.annotations.Nullable,
        org.jspecify.annotations.Nullable,
    ].collect { it.name }

    private static final String NULL_UNMARKED_ANNOTATION = org.jspecify.annotations.NullUnmarked.class.name

    NullabilityBreakingChangesRule(Map<String, Object> params) {
        super(params)
    }

    @Override

import java.io.OutputStreamWriter;
import java.io.Reader;
import java.io.Writer;
import java.nio.CharBuffer;
import java.util.Arrays;
import java.util.logging.Logger;
import org.jspecify.annotations.NullUnmarked;
import org.jspecify.annotations.Nullable;

/**
 * {@link SourceSinkFactory} implementations.
 *
 * @author Colin Decker
 */
@NullUnmarked
public class SourceSinkFactories {

import java.util.function.IntFunction;
import java.util.function.Predicate;
import junit.framework.Test;
import junit.framework.TestCase;
import junit.framework.TestSuite;
import org.jspecify.annotations.NullUnmarked;
import org.jspecify.annotations.Nullable;

/**
 * Unit test for {@link ForwardingMap}.
 *
 * @author Hayward Chan
 * @author Louis Wasserman
 */
@NullUnmarked