@Test
  public void toIntArray_lengthNotMutipleOfFour_throws() {
    byte[] data = Random.randBytes(26);
    assertThrows(IllegalArgumentException.class, () -> ChaCha20Util.toIntArray(data));
  }
https://datatracker.ietf.org/doc/html/rfc7539#section-2.3.2
java_src/src/test/java/com/google/crypto/tink/aead/internal/ChaCha20UtilTest.java