* class could be unloaded after the above call to `getEnumConstants` but before we call
     * `get()`, but that is vanishingly unlikely.
     */
    return ref == null ? Optional.absent() : Optional.fromNullable(enumClass.cast(ref.get()));
  }

  static String formatCompact4Digits(double value) {
    return String.format(Locale.ROOT, "%.4g", value);
  }

  static boolean stringIsNullOrEmpty(@Nullable String string) {

        .Builder()
        .addUnsafeNonAscii("header1", "valué1")
        .build()
    assertThat(headers.toString()).isEqualTo("header1: valué1\n")
  }

  // Fails on JS, ClassCastException: Illegal cast
  @Test fun ofMapThrowsOnNull() {
    assertFailsWith<NullPointerException> {
      (mapOf("User-Agent" to null) as Map<String, String>).toHeaders()
    }
  }

  @Test fun toMultimapGroupsHeaders() {

    @ParametricNullness
    public V apply(@ParametricNullness K key) {
      V result = map.get(key);
      checkArgument(result != null || map.containsKey(key), "Key '%s' not present in map", key);
      // The unchecked cast is safe because of the containsKey check.
      return uncheckedCastNullableTToT(result);
    }

    @Override
    public boolean equals(@Nullable Object o) {
      if (o instanceof FunctionForMapNoDefault) {

   *
   * - https://github.com/jspecify/jspecify/issues/65
   *
   * - https://github.com/jspecify/jdk/commit/71d826792b8c7ef95d492c50a274deab938f2552
   */
  /*
   * TODO(cpovirk): Is the unchecked cast avoidable? Would System.arraycopy be similarly fast (if
   * likewise not type-checked)? Could our single caller do something different?
   */
  @SuppressWarnings({"nullness", "unchecked"})

                return entry.getValue().get(columnKey);
              }

              @Override
              public V setValue(V value) {
                /*
                 * The cast is safe because of the containsKey check above. (Well, it's possible for
                 * the map to change between that call and this one. But if that happens, the

import junit.framework.TestSuite;
import org.jspecify.annotations.NullUnmarked;

/**
 * Test suite covering {@link Ints#asList(int[])}.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible
@SuppressWarnings("cast") // redundant casts are intentional and harmless
@NullUnmarked
@AndroidIncompatible // test-suite builders
public class IntArrayAsListTest extends TestCase {

  private static List<Integer> asList(Integer[] values) {

   */
  @SuppressWarnings("nullness")
  @ParametricNullness
  static <T extends @Nullable Object> T uncheckedCastNullableTToT(@Nullable T t) {
    return t;
  }

  /**
   * Returns {@code null} cast to any type.
   *
   * <p>This method is intended to help with usages of type parameters that have {@linkplain
   * ParametricNullness parametric nullness}. Sometimes, code may receive a null {@code T} but store

   *
   * - https://github.com/jspecify/jspecify/issues/65
   *
   * - https://github.com/jspecify/jdk/commit/71d826792b8c7ef95d492c50a274deab938f2552
   */
  /*
   * TODO(cpovirk): Is the unchecked cast avoidable? Would System.arraycopy be similarly fast (if
   * likewise not type-checked)? Could our single caller do something different?
   */
  @SuppressWarnings({"nullness", "unchecked"})

    // With a boxed predicate, no overloads can be selected in phase 1
    // ambiguous without the call to .booleanValue to unbox the Boolean
    checkState(boxedBoolean.booleanValue(), "", 1);
    // ambiguous without the cast to Object because the boxed predicate prevents any overload from
    // being selected in phase 1
    checkState(boxedBoolean, "", (Object) boxedLong);

    // With a boxed predicate, no overloads can be selected in phase 1
    // ambiguous without the call to .booleanValue to unbox the Boolean
    checkState(boxedBoolean.booleanValue(), "", 1);
    // ambiguous without the cast to Object because the boxed predicate prevents any overload from
    // being selected in phase 1
    checkState(boxedBoolean, "", (Object) boxedLong);