parentBuilder) {
    List<TestSuite> derived = super.createDerivedSuites(parentBuilder);
    // TODO(cpovirk): consider using this approach (derived suites instead of extension) in
    // ListTestSuiteBuilder, etc.?
    derived.add(
        MapTestSuiteBuilder.using(new MapGenerator<K, V>(parentBuilder.getSubjectGenerator()))
            .withFeatures(parentBuilder.getFeatures())

import org.junit.Ignore;

/**
 * Tests for {@link Multimap#get(Object)}.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
@Ignore("test runners must not instantiate and run this directly, only via suites we build")
// @Ignore affects the Android test runner, which respects JUnit 4 annotations on JUnit 3 tests.
@SuppressWarnings("JUnit4ClassUsedInJUnit3")

 * directly; please see {@link com.google.common.collect.testing.CollectionTestSuiteBuilder}.
 *
 * @author Chris Povirk
 */
@GwtCompatible
@Ignore("test runners must not instantiate and run this directly, only via suites we build")
// @Ignore affects the Android test runner, which respects JUnit 4 annotations on JUnit 3 tests.
@SuppressWarnings("JUnit4ClassUsedInJUnit3")
@NullMarked

import java.util.TreeSet;
import org.jspecify.annotations.Nullable;

/**
 * A wrapper around {@code TreeSet} that aggressively checks to see if elements are mutually
 * comparable. This implementation passes the navigable set test suites.
 *
 * @author Louis Wasserman
 */
@GwtIncompatible
public final class SafeTreeSet<E> implements Serializable, NavigableSet<E> {
  @SuppressWarnings("unchecked")

import java.util.Set;
import org.junit.Ignore;

/**
 * Tests for {@link Multimap#asMap}.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
@Ignore("test runners must not instantiate and run this directly, only via suites we build")
// @Ignore affects the Android test runner, which respects JUnit 4 annotations on JUnit 3 tests.
@SuppressWarnings("JUnit4ClassUsedInJUnit3")

 * com.google.common.collect.testing.MapTestSuiteBuilder}.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
@Ignore("test runners must not instantiate and run this directly, only via suites we build")
// @Ignore affects the Android test runner, which respects JUnit 4 annotations on JUnit 3 tests.
@SuppressWarnings("JUnit4ClassUsedInJUnit3")
public class MapMergeTester<K, V> extends AbstractMapTester<K, V> {

import org.junit.Ignore;

/**
 * Superclass for all {@code Multimap} testers.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
@Ignore("test runners must not instantiate and run this directly, only via suites we build")
// @Ignore affects the Android test runner, which respects JUnit 4 annotations on JUnit 3 tests.
@SuppressWarnings("JUnit4ClassUsedInJUnit3")
@NullMarked
public abstract class AbstractMultimapTester<

        // Given
        byte[] key = "testkey1".getBytes(); // 8 bytes for DES
        byte[] plaintext = "12345678".getBytes(); // 8 bytes (DES block size)

        // When
        Cipher desCipher = Crypto.getDES(key);
        desCipher.init(Cipher.ENCRYPT_MODE, new SecretKeySpec(key, "DES"));
        byte[] encrypted = desCipher.doFinal(plaintext);

        // Then
        assertNotNull(encrypted);

import java.util.TreeMap;
import org.jspecify.annotations.Nullable;

/**
 * A wrapper around {@code TreeMap} that aggressively checks to see if keys are mutually comparable.
 * This implementation passes the navigable map test suites.
 *
 * @author Louis Wasserman
 */
@GwtIncompatible
public final class SafeTreeMap<K, V> implements Serializable, NavigableMap<K, V> {
  @SuppressWarnings("unchecked")

 *  * BER: Basic Encoding Rules.
 *
 * This class was implemented according to the [X.690 spec][[x690]], and under the advice of
 * [Lets Encrypt's ASN.1 and DER][asn1_and_der] guide.
 *
 * [x690]: https://www.itu.int/rec/T-REC-X.690
 * [asn1_and_der]: https://letsencrypt.org/docs/a-warm-welcome-to-asn1-and-der/
 */
internal class DerReader(
  source: Source,
) {