From b858bd89a51575b4122740ba73009302473b76a0 Mon Sep 17 00:00:00 2001
From: Alan Szepieniec <alan@neptune.cash>
Date: Tue, 25 Jul 2023 17:33:33 +0200
Subject: [PATCH] derive BFieldCodec for MutatorSetAccumulator

---
 src/util_types/mutator_set/active_window.rs   |  1 +
 .../mutator_set/mutator_set_accumulator.rs    | 19 +------------------
 2 files changed, 2 insertions(+), 18 deletions(-)

diff --git a/src/util_types/mutator_set/active_window.rs b/src/util_types/mutator_set/active_window.rs
index 066d2551..a11aa25c 100644
--- a/src/util_types/mutator_set/active_window.rs
+++ b/src/util_types/mutator_set/active_window.rs
@@ -13,6 +13,7 @@ use super::shared::{CHUNK_SIZE, WINDOW_SIZE};
 pub struct ActiveWindow<H: AlgebraicHasher + BFieldCodec> {
     // It's OK to store this in memory, since it's on the size of kilobytes, not gigabytes.
     pub sbf: Vec<u32>,
+    #[bfield_codec(ignore)]
     _hasher: PhantomData<H>,
 }
 
diff --git a/src/util_types/mutator_set/mutator_set_accumulator.rs b/src/util_types/mutator_set/mutator_set_accumulator.rs
index 4cea6b92..6921a11c 100644
--- a/src/util_types/mutator_set/mutator_set_accumulator.rs
+++ b/src/util_types/mutator_set/mutator_set_accumulator.rs
@@ -13,7 +13,7 @@ use super::{
     mutator_set_trait::MutatorSet, removal_record::RemovalRecord,
 };
 
-#[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize, GetSize)]
+#[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize, GetSize, BFieldCodec)]
 pub struct MutatorSetAccumulator<H: AlgebraicHasher + BFieldCodec> {
     pub kernel: MutatorSetKernel<H, MmrAccumulator<H>>,
 }
@@ -95,23 +95,6 @@ impl<H: AlgebraicHasher + BFieldCodec> MutatorSet<H> for MutatorSetAccumulator<H
     }
 }
 
-impl<H: AlgebraicHasher + BFieldCodec> BFieldCodec for MutatorSetAccumulator<H> {
-    fn decode(
-        sequence: &[twenty_first::shared_math::b_field_element::BFieldElement],
-    ) -> anyhow::Result<Box<Self>> {
-        let kernel = *MutatorSetKernel::decode(sequence)?;
-        Ok(Box::new(Self { kernel }))
-    }
-
-    fn encode(&self) -> Vec<twenty_first::shared_math::b_field_element::BFieldElement> {
-        self.kernel.encode()
-    }
-
-    fn static_length() -> Option<usize> {
-        None
-    }
-}
-
 #[cfg(test)]
 mod ms_accumulator_tests {
     use crate::util_types::test_shared::mutator_set::*;