From 207cf4eba262e606413f86ea75479752f21577af Mon Sep 17 00:00:00 2001
From: Sean Bowe <ewillbefull@gmail.com>
Date: Fri, 14 Oct 2016 12:24:16 -0600
Subject: [PATCH] Add 'normalize' to Group trait for converting something into
 affine.

---
 src/groups/mod.rs      |  2 +-
 src/lib.rs             | 17 +++++++++++++++++
 tests/serialization.rs |  9 +++++++++
 3 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/src/groups/mod.rs b/src/groups/mod.rs
index 4afb8fd..60338c0 100644
--- a/src/groups/mod.rs
+++ b/src/groups/mod.rs
@@ -130,7 +130,7 @@ impl<P: GroupParams> G<P> {
 }
 
 impl<P: GroupParams> AffineG<P> {
-    fn to_jacobian(&self) -> G<P> {
+    pub fn to_jacobian(&self) -> G<P> {
         G {
             x: self.x,
             y: self.y,
diff --git a/src/lib.rs b/src/lib.rs
index 420a6fd..2212da7 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -73,6 +73,7 @@ pub trait Group:
     fn one() -> Self;
     fn random<R: Rng>(rng: &mut R) -> Self;
     fn is_zero(&self) -> bool;
+    fn normalize(&mut self);
 }
 
 #[derive(Copy, Clone, PartialEq, Eq, RustcDecodable, RustcEncodable)]
@@ -84,6 +85,14 @@ impl Group for G1 {
     fn one() -> Self { G1(groups::G1::one()) }
     fn random<R: Rng>(rng: &mut R) -> Self { G1(groups::G1::random(rng)) }
     fn is_zero(&self) -> bool { self.0.is_zero() }
+    fn normalize(&mut self) {
+        let new = match self.0.to_affine() {
+            Some(a) => a,
+            None => return
+        };
+
+        self.0 = new.to_jacobian();
+    }
 }
 
 impl Add<G1> for G1 {
@@ -119,6 +128,14 @@ impl Group for G2 {
     fn one() -> Self { G2(groups::G2::one()) }
     fn random<R: Rng>(rng: &mut R) -> Self { G2(groups::G2::random(rng)) }
     fn is_zero(&self) -> bool { self.0.is_zero() }
+    fn normalize(&mut self) {
+        let new = match self.0.to_affine() {
+            Some(a) => a,
+            None => return
+        };
+
+        self.0 = new.to_jacobian();
+    }
 }
 
 impl Add<G2> for G2 {
diff --git a/tests/serialization.rs b/tests/serialization.rs
index 9377312..88c928e 100644
--- a/tests/serialization.rs
+++ b/tests/serialization.rs
@@ -36,6 +36,10 @@ fn group_serialization_and_deserialization() {
 
         assert!(reserialize(a) == a);
         assert!(reserialize(reserialize(a)) == a);
+        let mut c = a;
+        c.normalize();
+
+        assert!(a == c);
     }
 
     let mut a = G2::one();
@@ -44,6 +48,11 @@ fn group_serialization_and_deserialization() {
 
         assert!(reserialize(a) == a);
         assert!(reserialize(reserialize(a)) == a);
+        let mut c = a;
+        c.normalize();
+
+        assert!(a == c);
+
     }
 }