checkNotNull(other);
    checkArgument(this.domain.equals(other.domain));
    if (other.isEmpty()) {
      return other;
    } else {
      C lowerEndpoint = Ordering.<C>natural().max(this.first(), other.first());
      C upperEndpoint = Ordering.<C>natural().min(this.last(), other.last());
      return (lowerEndpoint.compareTo(upperEndpoint) <= 0)
          ? ContiguousSet.create(Range.closed(lowerEndpoint, upperEndpoint), domain)

import com.google.common.base.Function;
import com.google.common.base.Functions;
import com.google.common.base.Joiner;
import com.google.common.base.Predicate;
import com.google.common.collect.Ordering;
import com.google.common.primitives.UnsignedInteger;
import com.google.common.primitives.UnsignedLong;
import com.google.common.testing.ForwardingWrapperTester;
import com.google.common.testing.NullPointerTester;

  protected abstract Multiset<AnEnum> create(AnEnum[] elements);

  @Override
  public AnEnum[] createArray(int length) {
    return new AnEnum[length];
  }

  /** Sorts the enums according to their natural ordering. */
  /*
   * While the current implementation returns `this`, that's not something we mean to guarantee.
   * Callers of TestContainerGenerator.order need to be prepared for implementations to return a new
   * collection.

import org.jspecify.annotations.NullUnmarked;

/** Unit tests for {@link Service} */
@NullUnmarked
@GwtIncompatible
@J2ktIncompatible
public class ServiceTest extends TestCase {

  /** Assert on the comparison ordering of the State enum since we guarantee it. */
  public void testStateOrdering() {
    // List every valid (direct) state transition.
    assertLessThan(NEW, STARTING);
    assertLessThan(NEW, TERMINATED);

  }

  protected abstract Set<AnEnum> create(AnEnum[] elements);

  @Override
  public AnEnum[] createArray(int length) {
    return new AnEnum[length];
  }

  /** Sorts the enums according to their natural ordering. */
  /*
   * While the current implementation returns `this`, that's not something we mean to guarantee.
   * Callers of TestContainerGenerator.order need to be prepared for implementations to return a new
   * collection.

import org.apache.maven.model.Plugin;
import org.apache.maven.model.PluginContainer;

/** @deprecated */
@Deprecated
public final class ModelUtils {

    /**
     * This should be the resulting ordering of plugins after merging:
     * <p>
     * Given:
     * <pre>
     * parent: X -&gt; A -&gt; B -&gt; D -&gt; E
     * child: Y -&gt; A -&gt; C -&gt; D -&gt; F
     * </pre>
     * Result:
     * <pre>

  }

  protected abstract Set<AnEnum> create(AnEnum[] elements);

  @Override
  public AnEnum[] createArray(int length) {
    return new AnEnum[length];
  }

  /** Sorts the enums according to their natural ordering. */
  /*
   * While the current implementation returns `this`, that's not something we mean to guarantee.
   * Callers of TestContainerGenerator.order need to be prepared for implementations to return a new
   * collection.

import com.google.common.base.Function;
import com.google.common.base.Functions;
import com.google.common.base.Joiner;
import com.google.common.base.Predicate;
import com.google.common.collect.Ordering;
import com.google.common.primitives.UnsignedInteger;
import com.google.common.primitives.UnsignedLong;
import com.google.common.testing.ForwardingWrapperTester;
import com.google.common.testing.NullPointerTester;

@SuppressWarnings("JUnit4ClassUsedInJUnit3")
public class ListToArrayTester<E> extends AbstractListTester<E> {
  // CollectionToArrayTester tests everything except ordering.

  public void testToArray_noArg() {
    Object[] actual = getList().toArray();
    assertArrayEquals("toArray() order should match list", createOrderedArray(), actual);
  }

  @CollectionSize.Require(absent = ZERO)

  protected abstract Multiset<AnEnum> create(AnEnum[] elements);

  @Override
  public AnEnum[] createArray(int length) {
    return new AnEnum[length];
  }

  /** Sorts the enums according to their natural ordering. */
  /*
   * While the current implementation returns `this`, that's not something we mean to guarantee.
   * Callers of TestContainerGenerator.order need to be prepared for implementations to return a new
   * collection.