@CollectionSize.Require(absent = ZERO)
  public void testAdd_supportedNullPresent() {
    E[] array = createArrayWithNullElement();
    collection = getSubjectGenerator().create(array);
    assertTrue("add(nullPresent) should return true", getList().add(null));

    List<E> expected = copyToList(array);
    expected.add(null);
    expectContents(expected);
  }

  /**

package com.google.common.collect.testing;

import static com.google.common.collect.testing.Helpers.copyToSet;
import static com.google.common.collect.testing.features.FeatureUtil.addImpliedFeatures;
import static java.util.Arrays.asList;

import com.google.common.annotations.GwtIncompatible;
import com.google.common.collect.testing.features.CollectionSize;
import com.google.common.collect.testing.features.Feature;
import java.lang.reflect.Method;

import static java.lang.reflect.Modifier.PRIVATE;
import static java.lang.reflect.Modifier.PROTECTED;
import static java.lang.reflect.Modifier.PUBLIC;
import static java.util.Arrays.asList;

import com.google.common.base.Optional;
import com.google.common.reflect.ClassPath;
import com.google.common.reflect.ClassPath.ClassInfo;
import com.google.common.reflect.TypeToken;

import static com.google.common.collect.testing.features.MapFeature.REJECTS_DUPLICATES_AT_CREATION;
import static com.google.common.collect.testing.testers.ReflectionFreeAssertThrows.assertThrows;
import static java.util.Arrays.asList;

import com.google.common.annotations.GwtCompatible;
import com.google.common.annotations.GwtIncompatible;
import com.google.common.annotations.J2ktIncompatible;

    }

    /**
     * Converts an array of {@literal CharSequence} to a {@literal List} of {@literal String}.
     *
     * @param array
     *            An array of {@literal CharSequence}
     * @return A {@literal List} of {@literal String}
     */
    protected static List<String> toStringList(final CharSequence[] array) {
        final List<String> list = newArrayList(array.length);

  override fun removeValue(s: String) {
    delegate!!.removeValue(s)
  }

  override fun getValueNames(): Array<String> = delegate!!.valueNames

  @Throws(SSLPeerUnverifiedException::class)
  override fun getPeerCertificates(): Array<Certificate>? = delegate!!.peerCertificates

  override fun getLocalCertificates(): Array<Certificate>? = delegate!!.localCertificates

  @Suppress("removal", "OVERRIDE_DEPRECATION")

    return new Unhashables();
  }

  @Override
  public T create(Object... elements) {
    UnhashableObject[] array = createArray(elements.length);
    int i = 0;
    for (Object e : elements) {
      array[i++] = (UnhashableObject) e;
    }
    return create(array);
  }

  /**
   * Creates a new collection containing the given elements; implement this method instead of {@link
   * #create(Object...)}.

import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
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
 */

import com.google.common.testing.EqualsTester;
import com.google.common.testing.ForwardingWrapperTester;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.Arrays;
import java.util.Collection;
import java.util.HashMap;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;

import java.io.IOException;
import java.io.OutputStreamWriter;
import java.io.Writer;
import java.nio.charset.StandardCharsets;
import java.security.MessageDigest;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

import org.apache.maven.api.DependencyScope;
import org.apache.maven.artifact.factory.ArtifactFactory;
import org.apache.maven.artifact.repository.ArtifactRepository;