From d2df10d78036f6fb4e0dae5c7287e4523bd8b47d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jan=20Bene=C5=A1?= <janbenes1234@gmail.com>
Date: Tue, 7 May 2024 17:26:00 +0200
Subject: [PATCH] refactor: nuking `GrumpkinScalar` (#6240)

All the aztec usecases were already replaced with a GrumpkinPrivateKey
which is basically a duplicate of GrumpkinScalar.

Fixes https://github.com/noir-lang/noir/issues/4968
---
 .../aztec/src/keys/point_to_symmetric_key.nr  |  2 +-
 .../abis/nullifier_key_validation_request.nr  |  3 +--
 .../crates/types/src/grumpkin_private_key.nr  |  2 +-
 .../noir_stdlib/src/grumpkin_scalar.nr        | 22 -------------------
 noir/noir-repo/noir_stdlib/src/lib.nr         |  1 -
 5 files changed, 3 insertions(+), 27 deletions(-)
 delete mode 100644 noir/noir-repo/noir_stdlib/src/grumpkin_scalar.nr

diff --git a/noir-projects/aztec-nr/aztec/src/keys/point_to_symmetric_key.nr b/noir-projects/aztec-nr/aztec/src/keys/point_to_symmetric_key.nr
index 905a049f9d5..1c80662dcb3 100644
--- a/noir-projects/aztec-nr/aztec/src/keys/point_to_symmetric_key.nr
+++ b/noir-projects/aztec-nr/aztec/src/keys/point_to_symmetric_key.nr
@@ -1,5 +1,5 @@
 use dep::protocol_types::{constants::GENERATOR_INDEX__SYMMETRIC_KEY, grumpkin_private_key::GrumpkinPrivateKey, grumpkin_point::GrumpkinPoint, utils::arr_copy_slice};
-use dep::std::{hash::sha256, grumpkin_scalar::GrumpkinScalar, embedded_curve_ops::multi_scalar_mul};
+use dep::std::{hash::sha256, embedded_curve_ops::multi_scalar_mul};
 
 // TODO(#5726): This function is called deriveAESSecret in TS. I don't like point_to_symmetric_key name much since
 // point is not the only input of the function. Unify naming with TS once we have a better name.
diff --git a/noir-projects/noir-protocol-circuits/crates/types/src/abis/nullifier_key_validation_request.nr b/noir-projects/noir-protocol-circuits/crates/types/src/abis/nullifier_key_validation_request.nr
index 1a08e9f7a2f..bab8b642f09 100644
--- a/noir-projects/noir-protocol-circuits/crates/types/src/abis/nullifier_key_validation_request.nr
+++ b/noir-projects/noir-protocol-circuits/crates/types/src/abis/nullifier_key_validation_request.nr
@@ -3,12 +3,11 @@ use crate::{
     address::AztecAddress,
     constants::{NULLIFIER_KEY_VALIDATION_REQUEST_CONTEXT_LENGTH, NULLIFIER_KEY_VALIDATION_REQUEST_LENGTH},
     traits::{Empty, Serialize, Deserialize}, grumpkin_point::GrumpkinPoint,
-    grumpkin_private_key::GrumpkinPrivateKey
 };
 
 struct NullifierKeyValidationRequest {
     master_nullifier_public_key: GrumpkinPoint,
-    app_nullifier_secret_key: Field, // not a GrumpkinScalar because it's output of poseidon2
+    app_nullifier_secret_key: Field, // not a grumpkin scalar because it's output of poseidon2
 }
 
 impl Eq for NullifierKeyValidationRequest {
diff --git a/noir-projects/noir-protocol-circuits/crates/types/src/grumpkin_private_key.nr b/noir-projects/noir-protocol-circuits/crates/types/src/grumpkin_private_key.nr
index 20b43f7aebc..79261ec4f20 100644
--- a/noir-projects/noir-protocol-circuits/crates/types/src/grumpkin_private_key.nr
+++ b/noir-projects/noir-protocol-circuits/crates/types/src/grumpkin_private_key.nr
@@ -1,4 +1,4 @@
-use dep::std::{cmp::Eq, grumpkin_scalar::GrumpkinScalar, embedded_curve_ops::fixed_base_scalar_mul};
+use dep::std::{cmp::Eq, embedded_curve_ops::fixed_base_scalar_mul};
 use crate::{
     grumpkin_point::GrumpkinPoint,
     traits::Empty
diff --git a/noir/noir-repo/noir_stdlib/src/grumpkin_scalar.nr b/noir/noir-repo/noir_stdlib/src/grumpkin_scalar.nr
deleted file mode 100644
index dd4b029d0a7..00000000000
--- a/noir/noir-repo/noir_stdlib/src/grumpkin_scalar.nr
+++ /dev/null
@@ -1,22 +0,0 @@
-// TODO(https://github.com/noir-lang/noir/issues/4968): move to aztec noir-protocol-circuits
-struct GrumpkinScalar {
-    low: Field,
-    high: Field,
-}
-
-impl GrumpkinScalar {
-    pub fn new(low: Field, high: Field) -> Self {
-        // TODO: check that the low and high value fit within the grumpkin modulus
-        GrumpkinScalar { low, high }
-    }
-}
-
-global GRUMPKIN_SCALAR_SERIALIZED_LEN: Field = 2;
-
-pub fn deserialize_grumpkin_scalar(fields: [Field; GRUMPKIN_SCALAR_SERIALIZED_LEN]) -> GrumpkinScalar {
-    GrumpkinScalar { low: fields[0], high: fields[1] }
-}
-
-pub fn serialize_grumpkin_scalar(scalar: GrumpkinScalar) -> [Field; GRUMPKIN_SCALAR_SERIALIZED_LEN] {
-    [scalar.low, scalar.high]
-}
diff --git a/noir/noir-repo/noir_stdlib/src/lib.nr b/noir/noir-repo/noir_stdlib/src/lib.nr
index 73fc7a28417..900cacb3cb6 100644
--- a/noir/noir-repo/noir_stdlib/src/lib.nr
+++ b/noir/noir-repo/noir_stdlib/src/lib.nr
@@ -6,7 +6,6 @@ mod schnorr;
 mod ecdsa_secp256k1;
 mod ecdsa_secp256r1;
 mod eddsa;
-mod grumpkin_scalar;
 mod embedded_curve_ops;
 mod sha256;
 mod sha512;