/** Test method for {@link GroupElement#toP2()}. */
@Test
public void testToP2() {
GroupElement p3zero = curve.getZero(GroupElement.Representation.P3);
GroupElement t = p3zero.toP2();
assertThat(t.repr, is(GroupElement.Representation.P2));
assertThat(t.X, is(p3zero.X));
assertThat(t.Y, is(p3zero.Y));
assertThat(t.Z, is(p3zero.Z));
assertThat(t.T, is((FieldElement) null));
GroupElement B = ed25519.getB();
t = B.toP2();
assertThat(t.repr, is(GroupElement.Representation.P2));
assertThat(t.X, is(B.X));
assertThat(t.Y, is(B.Y));
assertThat(t.Z, is(B.Z));
assertThat(t.T, is((FieldElement) null));
}
@Test(expected = IllegalArgumentException.class)
public void toP2ThrowsIfGroupElementHasCachedRepresentation() {
// Arrange:
final GroupElement g =
MathUtils.toRepresentation(
MathUtils.getRandomGroupElement(), GroupElement.Representation.CACHED);
// Assert:
g.toP2();
}
@Test
public void toP2ReturnsExpectedResultIfGroupElementHasP3Representation() {
for (int i = 0; i < 10; i++) {
// Arrange:
final GroupElement g = MathUtils.getRandomGroupElement();
// Act:
final GroupElement h1 = g.toP2();
final GroupElement h2 = MathUtils.toRepresentation(g, GroupElement.Representation.P2);
// Assert:
Assert.assertThat(h1, IsEqual.equalTo(h2));
Assert.assertThat(h1.getRepresentation(), IsEqual.equalTo(GroupElement.Representation.P2));
Assert.assertThat(h1.getX(), IsEqual.equalTo(g.getX()));
Assert.assertThat(h1.getY(), IsEqual.equalTo(g.getY()));
Assert.assertThat(h1.getZ(), IsEqual.equalTo(g.getZ()));
Assert.assertThat(h1.getT(), IsEqual.equalTo(null));
}
}