@Test
  public void doubleJacobianPointInfinity() throws Exception {
    BigInteger modulus = BigInteger.TEN;
    EllipticCurvesUtil.JacobianEcPoint inf =
        EllipticCurvesUtil.toJacobianEcPoint(ECPoint.POINT_INFINITY, modulus);
    EllipticCurvesUtil.JacobianEcPoint inf2 =
        EllipticCurvesUtil.doubleJacobianPoint(inf, BigInteger.valueOf(3), modulus);
    assertThat(inf2.isInfinity()).isTrue();
  }
Unit tests for {@link com.google.crypto.tink.subtle.EllipticCurvesUtil}.
java_src/src/test/java/com/google/crypto/tink/internal/EllipticCurvesUtilTest.java