Merge pull request #103 from AleoHQ/fix/group-one

Fix/group one

compiler/src/group/edwards_bls12.rs

@@ -8,7 +8,7 @@ use snarkos_curves::{
 use snarkos_errors::gadgets::SynthesisError;
 use snarkos_gadgets::curves::edwards_bls12::EdwardsBlsGadget;
 use snarkos_models::{
-    curves::AffineCurve,
+    curves::{AffineCurve, One, TEModelParameters},
     gadgets::{
         curves::{FieldGadget, FpGadget, GroupGadget},
         r1cs::ConstraintSystem,
@@ -33,6 +33,11 @@ pub enum EdwardsGroupType {
 
 impl GroupType<Fq> for EdwardsGroupType {
     fn constant(string: String, span: Span) -> Result<Self, GroupError> {
+        // 1group = generator
+        if string.eq("1") {
+            return Ok(Self::one());
+        }
+
         let value =
             Self::edwards_affine_from_str(string.clone()).map_err(|_| GroupError::invalid_group(string, span))?;
 
@@ -104,7 +109,7 @@ impl GroupType<Fq> for EdwardsGroupType {
 
 impl EdwardsGroupType {
     pub fn edwards_affine_from_str(string: String) -> Result<EdwardsAffine, SynthesisError> {
-        // 0 or (0, 1)
+        // x or (x, y)
         match Fq::from_str(&string).ok() {
             Some(x) => EdwardsAffine::get_point_from_x(x, false).ok_or(SynthesisError::AssignmentMissing),
             None => EdwardsAffine::from_str(&string).map_err(|_| SynthesisError::AssignmentMissing),
@@ -122,7 +127,12 @@ impl EdwardsGroupType {
             _ => Err(SynthesisError::AssignmentMissing),
         }?;
 
-        Self::edwards_affine_from_str(affine_string)
+        // 1group = generator
+        if affine_string.eq("1") {
+            Ok(edwards_affine_one())
+        } else {
+            Self::edwards_affine_from_str(affine_string)
+        }
     }
 
     pub fn allocated<CS: ConstraintSystem<Fq>>(&self, mut cs: CS) -> Result<EdwardsBlsGadget, SynthesisError> {
@@ -317,6 +327,24 @@ impl ToBytesGadget<Fq> for EdwardsGroupType {
     }
 }
 
+fn edwards_affine_one() -> GroupAffine<EdwardsParameters> {
+    let (x, y) = EdwardsParameters::AFFINE_GENERATOR_COEFFS;
+
+    EdwardsAffine::new(x, y)
+}
+
+impl One for EdwardsGroupType {
+    fn one() -> Self {
+        let one = edwards_affine_one();
+
+        Self::Constant(one)
+    }
+
+    fn is_one(&self) -> bool {
+        self.eq(&Self::one())
+    }
+}
+
 impl std::fmt::Display for EdwardsGroupType {
     fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
         match self {

compiler/src/group/mod.rs

@@ -4,7 +4,7 @@ use crate::errors::GroupError;
 use leo_types::Span;
 
 use snarkos_models::{
-    curves::Field,
+    curves::{Field, One},
     gadgets::{
         r1cs::ConstraintSystem,
         utilities::{
@@ -25,6 +25,7 @@ pub trait GroupType<F: Field>:
     + Clone
     + Debug
     + Display
+    + One
     + EvaluateEqGadget<F>
     + EqGadget<F>
     + ConditionalEqGadget<F>

compiler/tests/group/mod.rs

@@ -9,10 +9,10 @@ use crate::{
 use leo_compiler::{group::edwards_bls12::EdwardsGroupType, ConstrainedValue};
 use leo_types::InputValue;
 
-use snarkos_curves::edwards_bls12::{EdwardsAffine, Fq};
+use snarkos_curves::edwards_bls12::{EdwardsAffine, EdwardsParameters, Fq};
 use snarkos_gadgets::curves::edwards_bls12::EdwardsBlsGadget;
 use snarkos_models::{
-    curves::Zero,
+    curves::{TEModelParameters, Zero},
     gadgets::{r1cs::TestConstraintSystem, utilities::alloc::AllocGadget},
 };
 use std::str::FromStr;
@@ -47,6 +47,13 @@ fn output_zero(program: EdwardsTestCompiler) {
     output_expected_constant(program, EdwardsAffine::zero())
 }
 
+fn output_one(program: EdwardsTestCompiler) {
+    let (x, y) = EdwardsParameters::AFFINE_GENERATOR_COEFFS;
+    let one = EdwardsAffine::new(x, y);
+
+    output_expected_constant(program, one)
+}
+
 #[test]
 fn test_zero() {
     let bytes = include_bytes!("zero.leo");
@@ -55,6 +62,14 @@ fn test_zero() {
     output_zero(program);
 }
 
+#[test]
+fn test_one() {
+    let bytes = include_bytes!("one.leo");
+    let program = parse_program(bytes).unwrap();
+
+    output_one(program)
+}
+
 #[test]
 fn test_point() {
     let point = EdwardsAffine::from_str(TEST_POINT_1).unwrap();

compiler/tests/group/one.leo

@@ -0,0 +1,3 @@
+function main() -> group {
+    return 1group
+}

examples/pedersen_hash/src/main.leo

@@ -19,7 +19,7 @@ circuit PedersenHash {
 
 // The 'pedersen_hash' main function.
 function main() -> group {
-    const parameters = [0group; 256];
+    const parameters = [1group; 256];
     const pedersen = PedersenHash::new(parameters);
     let input: bool[256] = [true; 256];
     return pedersen.hash(input)