// We don't know whether these are still in the cache, so we can't assert on the return
      // values of these removes, but the cache should be empty after the removes, regardless.
      keys.remove(1);
      keys.remove(2);
      assertFalse(keys.remove(null));
      assertFalse(keys.remove(6));
      assertFalse(keys.remove(-6));
      assertFalse(keys.removeAll(asList(null, 0, 15, 1500)));

      // We don't know whether these are still in the cache, so we can't assert on the return
      // values of these removes, but the cache should be empty after the removes, regardless.
      keys.remove(1);
      keys.remove(2);
      assertFalse(keys.remove(null));
      assertFalse(keys.remove(6));
      assertFalse(keys.remove(-6));
      assertFalse(keys.removeAll(asList(null, 0, 15, 1500)));

    assertThrows(UnsupportedOperationException.class, () -> collection.remove(e0()));
    expectUnchanged();
    assertTrue("remove(present) should not remove the element", collection.contains(e0()));
  }

  @CollectionFeature.Require(absent = SUPPORTS_REMOVE)
  public void testRemove_unsupportedNotPresent() {
    try {
      assertFalse(
          "remove(notPresent) should return false or throw UnsupportedOperationException",

      }

      @Override
      public void remove() {
        iterator.remove();
      }
    };
  }

  /**
   * Returns an iterator that cycles indefinitely over the provided elements.
   *
   * <p>The returned iterator supports {@code remove()}. After {@code remove()} is called,
   * subsequent cycles omit the removed element, but {@code elements} does not change. The

    int initialSize = getList().size();
    assertTrue("remove(present) should return true", getList().remove(duplicate));
    assertTrue(
        "After remove(duplicate), a list should still contain the duplicate element",
        getList().contains(duplicate));
    assertFalse(
        "remove(duplicate) should remove the first instance of the "
            + "duplicate element in the list",

        recurse(level + 1);
      }
    }
  }

  private void compareResultsForThisListOfStimuli() {
    int removes = frequency(asList(stimuli), remove);
    if ((!features.contains(IteratorFeature.SUPPORTS_REMOVE) && removes > 1)
        || (stimuli.length >= 5 && removes > 2)) {
      // removes are the most expensive thing to test, since they often throw exceptions with stack
      // traces, so we test them a bit less aggressively

      if (predicate.apply(list.get(n))) {
        list.remove(n);
      }
    }
    // And now remove everything in the range [to, from) (going backwards).
    for (int n = from - 1; n >= to; n--) {
      list.remove(n);
    }
  }

  /** Removes and returns the first matching element, or returns {@code null} if there is none. */
  @CheckForNull

  @MapFeature.Require(SUPPORTS_REMOVE)
  public void testRemoveAbsent() {
    assertFalse(multimap().remove(k0(), v1()));
    expectUnchanged();
  }

  @CollectionSize.Require(absent = ZERO)
  @MapFeature.Require(SUPPORTS_REMOVE)
  public void testRemovePresent() {
    assertTrue(multimap().remove(k0(), v0()));

    assertFalse(multimap().containsEntry(k0(), v0()));
    expectMissing(e0());

  @MapFeature.Require(SUPPORTS_REMOVE)
  public void testRemoveAbsent() {
    assertFalse(multimap().remove(k0(), v1()));
    expectUnchanged();
  }

  @CollectionSize.Require(absent = ZERO)
  @MapFeature.Require(SUPPORTS_REMOVE)
  public void testRemovePresent() {
    assertTrue(multimap().remove(k0(), v0()));

    assertFalse(multimap().containsEntry(k0(), v0()));
    expectMissing(e0());

    map.remove("a");
    assertFalse(underlying.containsKey("a"));

    Set<String> keys = map.keySet();
    keys.remove("b");
    assertFalse(underlying.containsKey("b"));

    Iterator<String> keyIterator = keys.iterator();
    keyIterator.next();
    keyIterator.remove();
    assertFalse(underlying.containsKey("c"));