Headers.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() {

    assertSip("SipHash", 0x8325093242a96f60L);
  }

  // Test for common pitfall regarding sign extension.
  // For example: (long) data[i++] | (long) data[i++] << 8 | ...
  // If data[i] == (byte) 0x80, the first cast will sign-extend it to 0xffffffffffffff80,
  // masking the remaining seven bytes.
  // To test this, we give an input where bit 7 is not cleared. For example:
  // (1) 00 01 02 03 04 05 06 07 80

    assertSip("SipHash", 0x8325093242a96f60L);
  }

  // Test for common pitfall regarding sign extension.
  // For example: (long) data[i++] | (long) data[i++] << 8 | ...
  // If data[i] == (byte) 0x80, the first cast will sign-extend it to 0xffffffffffffff80,
  // masking the remaining seven bytes.
  // To test this, we give an input where bit 7 is not cleared. For example:
  // (1) 00 01 02 03 04 05 06 07 80

                this.t = t;
            }
        }
    }

    @SuppressWarnings("unchecked")
    static <T extends Throwable> void uncheckedThrow(Throwable t) throws T {
        throw (T) t; // rely on vacuous cast
    }

   *
   * <p><b>{@code Stream} equivalent:</b> {@code stream.filter(type::isInstance).map(type::cast)}.
   * This does perform a little more work than necessary, so another option is to insert an
   * unchecked cast at some later point:
   *
   * <pre>
   * {@code @SuppressWarnings("unchecked") // safe because of ::isInstance check
   * ImmutableList<NewType> result =

  }

  private void updateInverseMap(
      @ParametricNullness K key,
      boolean containedKey,
      @CheckForNull V oldValue,
      @ParametricNullness V newValue) {
    if (containedKey) {
      // The cast is safe because of the containedKey check.
      removeFromInverseMap(uncheckedCastNullableTToT(oldValue));
    }
    inverse.delegate.put(newValue, key);
  }

  @CanIgnoreReturnValue
  @Override

      int n, @Nullable Entry<K, V>[] entryArray, boolean throwIfDuplicateKeys)
      throws BucketOverflowException {
    /*
     * The cast is safe: n==entryArray.length means that we have filled the whole array with Entry
     * instances, in which case it is safe to cast it from an array of nullable entries to an array
     * of non-null entries.
     */
    @SuppressWarnings("nullness")
    Entry<K, V>[] entries =

    ImmutableTypeToInstanceMap<Iterable<?>[]> map =
        ImmutableTypeToInstanceMap.<Iterable<?>[]>builder().put(type, array).build();
    assertEquals(1, map.size());
    // Redundant cast works around a javac bug.
    assertThat((Iterable<?>[]) map.getInstance(type)).asList().containsExactly(array[0]);
  }

  public void testWildcardType() {

    @Override
    @CheckForNull
    public V2 get(@CheckForNull Object rowKey, @CheckForNull Object columnKey) {
      // The function is passed a null input only when the table contains a null
      // value.
      // The cast is safe because of the contains() check.
      return contains(rowKey, columnKey)
          ? function.apply(uncheckedCastNullableTToT(fromTable.get(rowKey, columnKey)))
          : null;
    }

    @Override

   *
   * - 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"})