assertEquals(LOWER, Ascii.toLowerCase(UPPER));
    assertSame(LOWER, Ascii.toLowerCase(LOWER));
    assertEquals(IGNORED, Ascii.toLowerCase(IGNORED));
    assertEquals("foobar", Ascii.toLowerCase("fOobaR"));
  }

  public void testToUpperCase() {
    assertEquals(UPPER, Ascii.toUpperCase(LOWER));
    assertSame(UPPER, Ascii.toUpperCase(UPPER));
    assertEquals(IGNORED, Ascii.toUpperCase(IGNORED));

    assertEquals(LOWER, Ascii.toLowerCase(UPPER));
    assertSame(LOWER, Ascii.toLowerCase(LOWER));
    assertEquals(IGNORED, Ascii.toLowerCase(IGNORED));
    assertEquals("foobar", Ascii.toLowerCase("fOobaR"));
  }

  public void testToUpperCase() {
    assertEquals(UPPER, Ascii.toUpperCase(LOWER));
    assertSame(UPPER, Ascii.toUpperCase(UPPER));
    assertEquals(IGNORED, Ascii.toUpperCase(IGNORED));

  private Charsets() {}

  /**
   * US-ASCII: seven-bit ASCII, the Basic Latin block of the Unicode character set (ISO646-US).
   *
   * <p><b>Java 7+ users:</b> this constant should be treated as deprecated; use {@link
   * java.nio.charset.StandardCharsets#US_ASCII} instead.
   *
   */
  @J2ktIncompatible
  @GwtIncompatible // Charset not supported by GWT
  public static final Charset US_ASCII = Charset.forName("US-ASCII");

  /**

  private Charsets() {}

  /**
   * US-ASCII: seven-bit ASCII, the Basic Latin block of the Unicode character set (ISO646-US).
   *
   * <p><b>Java 7+ users:</b> this constant should be treated as deprecated; use {@link
   * java.nio.charset.StandardCharsets#US_ASCII} instead.
   *
   */
  @J2ktIncompatible
  @GwtIncompatible // Charset not supported by GWT
  public static final Charset US_ASCII = Charset.forName("US-ASCII");

  /**

// given ASCII character in the set. The 128-bits of the lower 16 bytes,
// starting with the least-significant bit of the lowest word to the
// most-significant bit of the highest word, map to the full range of all
// 128 ASCII characters. The 128-bits of the upper 16 bytes will be zeroed,
// ensuring that any non-ASCII character will be reported as not in the set.

   * This is like [toLowerCase] except that it does nothing if this contains any non-ASCII
   * characters. We want to avoid lower casing special chars like U+212A (Kelvin symbol) because
   * they can return ASCII characters that match real hostnames.
   */
  private fun String.asciiToLowercase(): String {
    return when {
      isAscii() -> lowercase(Locale.US) // This is an ASCII string.
      else -> this
    }
  }

          }
        };
    EscaperAsserts.assertBasic(deletingEscaper);
    assertEquals(
        "Everything outside the printable ASCII range is deleted.",
        deletingEscaper.escape(
            "\tEverything\0 outside the\uD800\uDC00 "
                + "printable ASCII \uFFFFrange is \u007Fdeleted.\n"));
  }

  public void testReplacementPriority() throws IOException {
    CharEscaper replacingEscaper =

 * the License.
 */

package com.google.common.collect;

import static com.google.common.truth.Truth.assertThat;

import com.google.common.annotations.GwtCompatible;
import com.google.common.base.Ascii;
import com.google.common.collect.testing.SpliteratorTester;
import java.util.Arrays;
import java.util.List;
import java.util.Spliterator;
import java.util.stream.DoubleStream;
import java.util.stream.IntStream;

 * lookups.
 *
 * <p>During construction, names are normalized in two ways:
 *
 * <ol>
 *   <li>ASCII uppercase characters are converted to lowercase.
 *   <li>Unicode dot separators other than the ASCII period ({@code '.'}) are converted to the ASCII
 *       period.
 * </ol>
 *
 * <p>The normalized values will be returned from {@link #toString()} and {@link #parts()}, and will

   * Parses the specified string as a signed decimal long value. The ASCII character {@code '-'} (
   * <code>'&#92;u002D'</code>) is recognized as the minus sign.
   *
   * <p>Unlike {@link Long#parseLong(String)}, this method returns {@code null} instead of throwing
   * an exception if parsing fails. Additionally, this method only accepts ASCII digits, and returns
   * {@code null} if non-ASCII digits are present in the string.
   *