@CollectionSize.Require(absent = ZERO)
  public void testRemoveFromInverseRemovesFromForward() {
    getMap().inverse().remove(v0());
    expectMissing(e0());
  }

  @MapFeature.Require(SUPPORTS_REMOVE)
  @CollectionSize.Require(absent = ZERO)
  public void testRemoveFromInverseKeySetRemovesFromForward() {
    getMap().inverse().keySet().remove(v0());
    expectMissing(e0());
  }

  @MapFeature.Require(SUPPORTS_REMOVE)

import java.io.Serializable;
import java.lang.reflect.Method;
import java.util.Collections;
import java.util.List;
import org.junit.Ignore;

/**
 * Tests for the {@code inverse} view of a BiMap.
 *
 * <p>This assumes that {@code bimap.inverse().inverse() == bimap}, which is not technically
 * required but is fulfilled by all current implementations.
 *
 * @author Louis Wasserman
 */
@GwtCompatible

  public abstract double transform(double x);

  /**
   * Returns the inverse linear transformation. The inverse of a horizontal transformation is a
   * vertical transformation, and vice versa. The inverse of the {@link #forNaN} transformation is
   * itself. In all other cases, the inverse is a transformation such that applying both the
   * original transformation and its inverse to a value gives you the original value give-or-take

      Entry<V, K> reversed = reverseEntry(entry);
      BiMap<V, K> inv = getMap().inverse();
      assertFalse(
          "Inverse should not contain entry " + reversed, inv.entrySet().contains(reversed));
      assertFalse(
          "Inverse should not contain key " + reversed.getKey(),
          inv.containsKey(reversed.getKey()));
      assertFalse(
          "Inverse should not contain value " + reversed.getValue(),

    assertFalse(getMap().containsKey(k0()));

    assertTrue(getMap().containsKey(k1()));
    assertTrue(getMap().inverse().containsKey(null));
    assertNull(getMap().get(k1()));
    assertEquals(k1(), getMap().inverse().get(null));
    assertEquals(1, getMap().size());
  }

  // nb: inverse is run through its own entire suite

  @MapFeature.Require(SUPPORTS_PUT)
  @CollectionSize.Require(ZERO)

  }

  AbstractBiMap<V, K> makeInverse(Map<V, K> backward) {
    return new Inverse<>(backward, this);
  }

  void setInverse(AbstractBiMap<V, K> inverse) {
    this.inverse = inverse;
  }

  // Query Operations (optimizations)

  @Override
  public boolean containsValue(@Nullable Object value) {
    return inverse.containsKey(value);
  }

  // Modification Operations

import java.io.Serializable;
import java.lang.reflect.Method;
import java.util.Collections;
import java.util.List;
import org.junit.Ignore;

/**
 * Tests for the {@code inverse} view of a BiMap.
 *
 * <p>This assumes that {@code bimap.inverse().inverse() == bimap}, which is not technically
 * required but is fulfilled by all current implementations.
 *
 * @author Louis Wasserman
 */
@GwtCompatible

        .inOrder();
    // backward map ordered by country
    assertThat(bimap.inverse().keySet())
        .containsExactly(Country.CANADA, Country.CHILE, Country.SWITZERLAND)
        .inOrder();
    // backward map ordered by country (even for currency values)
    assertThat(bimap.inverse().values())
        .containsExactly(Currency.DOLLAR, Currency.PESO, Currency.FRANC)
        .inOrder();
  }

        .isWithin(ALLOWED_ERROR)
        .of(x1 + xDelta);
    assertThat(transformation.slope()).isWithin(ALLOWED_ERROR).of(yDelta / xDelta);
    assertThat(transformation.inverse().slope()).isWithin(ALLOWED_ERROR).of(xDelta / yDelta);
    assertThat(transformation.inverse()).isSameInstanceAs(transformation.inverse());
    assertThat(transformation.inverse().inverse()).isSameInstanceAs(transformation);
  }

  /**

        ImmutableListMultimap.<String, Integer>of().inverse());
    assertEquals(ImmutableListMultimap.of(1, "one"), ImmutableListMultimap.of("one", 1).inverse());
    assertEquals(
        ImmutableListMultimap.of(1, "one", 2, "two"),
        ImmutableListMultimap.of("one", 1, "two", 2).inverse());
    assertEquals(
        ImmutableListMultimap.of("of", 'o', "of", 'f', "to", 't', "to", 'o').inverse(),