assertUnmodifiableIterableInTandem(
        unmodifiable.asMap().entrySet(), multimap.asMap().entrySet());

    assertEquals(multimap.toString(), unmodifiable.toString());
    assertEquals(multimap.hashCode(), unmodifiable.hashCode());
    assertEquals(multimap, unmodifiable);

    assertThat(unmodifiable.asMap().get("bar")).containsExactly(5, -1);

import org.jspecify.annotations.Nullable;

/**
 * An implementation of {@code Iterable} which throws an exception on all invocations of the {@link
 * #iterator()} method after the first, and whose iterator is always unmodifiable.
 *
 * <p>The {@code Iterable} specification does not make it absolutely clear what should happen on a
 * second invocation, so implementors have made various choices, including:
 *
 * <ul>

      nullableValueEntry.setValue(null);
      fail("setValue on unmodifiable Map.Entry succeeded");
    } catch (UnsupportedOperationException expected) {
    }
  }

  /**
   * Verifies that an Iterator is unmodifiable.
   *
   * <p>This test only works with iterators that iterate over a finite set.
   */

package com.google.common.collect.testing.google;

import static com.google.common.collect.testing.Helpers.getMethod;
import static com.google.common.collect.testing.IteratorFeature.MODIFIABLE;
import static com.google.common.collect.testing.IteratorFeature.UNMODIFIABLE;
import static com.google.common.collect.testing.features.CollectionFeature.KNOWN_ORDER;
import static com.google.common.collect.testing.features.CollectionFeature.SUPPORTS_ITERATOR_REMOVE;

      nullableValueEntry.setValue(null);
      fail("setValue on unmodifiable Map.Entry succeeded");
    } catch (UnsupportedOperationException expected) {
    }
  }

  /**
   * Verifies that an Iterator is unmodifiable.
   *
   * <p>This test only works with iterators that iterate over a finite set.
   */

   * interfaces.
   */
  public static final Set<IteratorFeature> UNMODIFIABLE = emptySet();

  /**
   * A set containing all of the optional features of the {@link Iterator} and {@link ListIterator}
   * interfaces.
   */
  public static final Set<IteratorFeature> MODIFIABLE =
      unmodifiableSet(new LinkedHashSet<>(asList(values())));

import static com.google.common.collect.testing.Helpers.copyToList;
import static com.google.common.collect.testing.Helpers.mapEntry;
import static com.google.common.collect.testing.IteratorFeature.MODIFIABLE;
import static com.google.common.collect.testing.IteratorFeature.UNMODIFIABLE;
import static com.google.common.collect.testing.features.CollectionFeature.ALLOWS_NULL_VALUES;
import static com.google.common.collect.testing.features.CollectionFeature.KNOWN_ORDER;

    }
  }

  private <T extends @Nullable Object> void actsLikeIteratorHelper(List<T> list) {
    // Check with modifiable copies of the list
    new PeekingIteratorTester<T>(list).test();

    // Check with unmodifiable lists
    new IteratorTester<T>(
        list.size() * 2 + 2, UNMODIFIABLE, list, IteratorTester.KnownOrder.KNOWN_ORDER) {
      @Override
      protected Iterator<T> newTargetIterator() {

   * equal.
   */
  boolean areEqual();

  /**
   * Returns an unmodifiable map containing the entries from the left map whose keys are not present
   * in the right map.
   */
  Map<K, V> entriesOnlyOnLeft();

  /**
   * Returns an unmodifiable map containing the entries from the right map whose keys are not
   * present in the left map.
   */

import static com.google.common.collect.testing.Helpers.copyToList;
import static com.google.common.collect.testing.Helpers.mapEntry;
import static com.google.common.collect.testing.IteratorFeature.MODIFIABLE;
import static com.google.common.collect.testing.IteratorFeature.UNMODIFIABLE;
import static com.google.common.collect.testing.features.CollectionFeature.ALLOWS_NULL_VALUES;
import static com.google.common.collect.testing.features.CollectionFeature.KNOWN_ORDER;