assertEquals(entry.getKey() + "=" + entry.getValue(), entry.toString());
      assertEquals(entry.getKey(), bimap.inverse().get(entry.getValue()));
    }

    assertEquals("{" + JOINER.join(map.entrySet()) + "}", map.toString());
    assertEquals("[" + JOINER.join(map.entrySet()) + "]", map.entrySet().toString());
    assertEquals("[" + JOINER.join(map.keySet()) + "]", map.keySet().toString());

    assertEquals(ASCII, Files.toString(asciiFile, US_ASCII));
    assertEquals(I18N, Files.toString(i18nFile, UTF_8));
    assertThat(Files.toString(i18nFile, US_ASCII)).isNotEqualTo(I18N);
  }

  public void testWriteString() throws IOException {
    File temp = createTempFile();
    Files.write(I18N, temp, UTF_16LE);
    assertEquals(I18N, Files.toString(temp, UTF_16LE));
  }

  public void testToStringEmpty() {
    assertEquals("{}", multimap().toString());
  }

  @CollectionSize.Require(ONE)
  @CollectionFeature.Require(absent = NON_STANDARD_TOSTRING)
  public void testToStringSingleton() {
    assertEquals("{" + k0() + "=[" + v0() + "]}", multimap().toString());
  }

  @CollectionSize.Require(absent = ZERO)
  @CollectionFeature.Require(absent = NON_STANDARD_TOSTRING)

        assertEquals("test      ", sb.toString());

        // Test with exact width string
        sb = new StringBuffer();
        ace.appendCol(sb, "exact", 5);
        assertEquals("exact", sb.toString());

        // Test with longer string than width
        sb = new StringBuffer();
        ace.appendCol(sb, "longer string", 5);
        assertEquals("longer string", sb.toString());
    }

    @Test

    assertEquals(":102", HostAndPort.fromString(":102").toString());
    assertEquals("[1::2]:103", HostAndPort.fromParts("1::2", 103).toString());
    assertEquals("[::1]:104", HostAndPort.fromString("[::1]:104").toString());

    // Without ports.
    assertEquals("foo", "" + HostAndPort.fromString("foo"));
    assertEquals("", HostAndPort.fromString("").toString());

    assertEquals(":102", HostAndPort.fromString(":102").toString());
    assertEquals("[1::2]:103", HostAndPort.fromParts("1::2", 103).toString());
    assertEquals("[::1]:104", HostAndPort.fromString("[::1]:104").toString());

    // Without ports.
    assertEquals("foo", "" + HostAndPort.fromString("foo"));
    assertEquals("", HostAndPort.fromString("").toString());

            queryBuf.append(lowerTerm != null ? "*".equals(Term.toString(lowerTerm)) ? "\\*" : Term.toString(lowerTerm) : "*");
            queryBuf.append(" TO ");
            final BytesRef upperTerm = termRangeQuery.getUpperTerm();
            queryBuf.append(upperTerm != null ? "*".equals(Term.toString(upperTerm)) ? "\\*" : Term.toString(upperTerm) : "*");
            queryBuf.append(termRangeQuery.includesUpper() ? ']' : '}');

  public void testToString_minimal() {
    assertNotNull("toString() should not return null", collection.toString());
  }

  @CollectionSize.Require(ZERO)
  @CollectionFeature.Require(absent = NON_STANDARD_TOSTRING)
  public void testToString_size0() {
    assertEquals("emptyCollection.toString should return []", "[]", collection.toString());
  }

  @CollectionSize.Require(ONE)

  }

  private static final Comparator<Object> TO_STRING =
      new Comparator<Object>() {
        @Override
        public int compare(Object o1, Object o2) {
          return o1.toString().compareTo(o2.toString());
        }
      };

  public void testSupertypeComparator() {
    SortedSet<Integer> set =
        new ImmutableSortedSet.Builder<Integer>(TO_STRING).add(3, 12, 101, 44).build();

 * @author Jared Levy
 * @since 2.0
 */
@GwtCompatible
public final class Functions {
  private Functions() {}

  /**
   * A function equivalent to the method reference {@code Object::toString}. The function simply
   * invokes {@code toString} on its argument and returns the result. It throws a {@link
   * NullPointerException} on null input.
   *
   * <p><b>Warning:</b> The returned function may not be <i>consistent with equals</i> (as