Use AffinePoint where appropriate

Author: daxpedda

ed448-goldilocks/src/curve/scalar_mul/variable_base.rs

@@ -56,7 +56,7 @@ mod test {
 
         // Lets see if this is conserved over the isogenies
         let edwards_point = twisted_point.to_untwisted();
-        let got_untwisted_point = edwards_point.scalar_mul(&scalar);
+        let got_untwisted_point = edwards_point.to_affine().scalar_mul(&scalar);
         let expected_untwisted_point = got.to_untwisted();
         assert_eq!(got_untwisted_point, expected_untwisted_point);
     }

ed448-goldilocks/src/curve/twedwards/extended.rs

@@ -197,7 +197,7 @@ mod tests {
             "ae05e9634ad7048db359d6205086c2b0036ed7a035884dd7b7e36d728ad8c4b80d6565833a2a3098bbbcb2bed1cda06bdaeafbcdea9386ed",
         );
         let a = AffinePoint { x, y }.to_extended();
-        let twist_a = a.to_untwisted().to_twisted();
+        let twist_a = a.to_untwisted().to_affine().to_twisted();
         assert_eq!(twist_a, a.double().double())
     }
 

ed448-goldilocks/src/decaf/points.rs

@@ -249,14 +249,14 @@ impl CurveGroup for DecafPoint {
     }
 }
 
-impl From<EdwardsPoint> for DecafPoint {
-    fn from(point: EdwardsPoint) -> Self {
+impl From<AffinePoint> for DecafPoint {
+    fn from(point: AffinePoint) -> Self {
         Self(point.to_twisted())
     }
 }
 
-impl From<&EdwardsPoint> for DecafPoint {
-    fn from(point: &EdwardsPoint) -> Self {
+impl From<&AffinePoint> for DecafPoint {
+    fn from(point: &AffinePoint) -> Self {
         Self(point.to_twisted())
     }
 }

ed448-goldilocks/src/edwards.rs

@@ -12,6 +12,6 @@
 pub(crate) mod affine;
 pub(crate) mod extended;
 mod scalar;
-pub use affine::AffinePoint;
-pub use extended::{CompressedEdwardsY, EdwardsPoint};
+pub use affine::{AffinePoint, CompressedEdwardsY};
+pub use extended::EdwardsPoint;
 pub use scalar::{EdwardsScalar, EdwardsScalarBytes, WideEdwardsScalarBytes};