From 26d95b4a0e0acdb81eb0020961bf48e1a7610868 Mon Sep 17 00:00:00 2001
From: Jack Grigg <jack@electriccoin.co>
Date: Wed, 26 Apr 2023 14:06:52 +0000
Subject: [PATCH 1/2] zcash_primitives: Temporarily expose v5 Sapling bundle
 parsing

This is currently exposed via `Transaction` for usage in `zcashd`, but
may be removed in future (if `zcashd` moves transaction parsing entirely
into Rust), or renamed and stabilised.
---
 zcash_primitives/CHANGELOG.md           |  5 +++++
 zcash_primitives/src/transaction/mod.rs | 26 +++++++++++++++++++++++--
 2 files changed, 29 insertions(+), 2 deletions(-)

diff --git a/zcash_primitives/CHANGELOG.md b/zcash_primitives/CHANGELOG.md
index b1cf2e126..dbc7d8fe1 100644
--- a/zcash_primitives/CHANGELOG.md
+++ b/zcash_primitives/CHANGELOG.md
@@ -6,6 +6,11 @@ and this library adheres to Rust's notion of
 [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ## [Unreleased]
+### Added
+- `zcash_primitives::transaction`:
+  - `Transaction::temporary_zcashd_read_v5_sapling`
+  - `Transaction::temporary_zcashd_write_v5_sapling`
+
 ### Changed
 - Bumped dependencies to `secp256k1 0.26`, `hdwallet 0.4`.
 - `zcash_primitives::transactions::component::amount::DEFAULT_FEE` increased zip317 
diff --git a/zcash_primitives/src/transaction/mod.rs b/zcash_primitives/src/transaction/mod.rs
index 5bd4af154..a500b54bb 100644
--- a/zcash_primitives/src/transaction/mod.rs
+++ b/zcash_primitives/src/transaction/mod.rs
@@ -730,6 +730,13 @@ impl Transaction {
         Ok((consensus_branch_id, lock_time, expiry_height))
     }
 
+    #[cfg(feature = "temporary-zcashd")]
+    pub fn temporary_zcashd_read_v5_sapling<R: Read>(
+        reader: R,
+    ) -> io::Result<Option<sapling::Bundle<sapling::Authorized>>> {
+        Self::read_v5_sapling(reader)
+    }
+
     #[allow(clippy::redundant_closure)]
     fn read_v5_sapling<R: Read>(
         mut reader: R,
@@ -917,8 +924,23 @@ impl Transaction {
         Ok(())
     }
 
-    pub fn write_v5_sapling<W: Write>(&self, mut writer: W) -> io::Result<()> {
-        if let Some(bundle) = &self.sapling_bundle {
+    #[cfg(feature = "temporary-zcashd")]
+    pub fn temporary_zcashd_write_v5_sapling<W: Write>(
+        sapling_bundle: Option<&sapling::Bundle<sapling::Authorized>>,
+        writer: W,
+    ) -> io::Result<()> {
+        Self::write_v5_sapling_inner(sapling_bundle, writer)
+    }
+
+    pub fn write_v5_sapling<W: Write>(&self, writer: W) -> io::Result<()> {
+        Self::write_v5_sapling_inner(self.sapling_bundle.as_ref(), writer)
+    }
+
+    fn write_v5_sapling_inner<W: Write>(
+        sapling_bundle: Option<&sapling::Bundle<sapling::Authorized>>,
+        mut writer: W,
+    ) -> io::Result<()> {
+        if let Some(bundle) = sapling_bundle {
             Vector::write(&mut writer, bundle.shielded_spends(), |w, e| {
                 e.write_v5_without_witness_data(w)
             })?;

From 8db7a071a0b79687d79ffc6894fe573944b16008 Mon Sep 17 00:00:00 2001
From: Jack Grigg <jack@electriccoin.co>
Date: Wed, 26 Apr 2023 15:33:48 +0000
Subject: [PATCH 2/2] zcash_primitives: `impl DynamicUsage for
 sapling::Bundle<Authorized>`

---
 zcash_primitives/CHANGELOG.md                 |  4 +++
 .../src/transaction/components/sapling.rs     | 28 +++++++++++++++++++
 2 files changed, 32 insertions(+)

diff --git a/zcash_primitives/CHANGELOG.md b/zcash_primitives/CHANGELOG.md
index dbc7d8fe1..001a41fc5 100644
--- a/zcash_primitives/CHANGELOG.md
+++ b/zcash_primitives/CHANGELOG.md
@@ -10,6 +10,10 @@ and this library adheres to Rust's notion of
 - `zcash_primitives::transaction`:
   - `Transaction::temporary_zcashd_read_v5_sapling`
   - `Transaction::temporary_zcashd_write_v5_sapling`
+- Implementations of `memuse::DynamicUsage` for the following types:
+  - `zcash_primitives::transaction::components::sapling`:
+    - `Bundle<Authorized>`
+    - `SpendDescription<Authorized>`
 
 ### Changed
 - Bumped dependencies to `secp256k1 0.26`, `hdwallet 0.4`.
diff --git a/zcash_primitives/src/transaction/components/sapling.rs b/zcash_primitives/src/transaction/components/sapling.rs
index dc1b66380..149bfdbd4 100644
--- a/zcash_primitives/src/transaction/components/sapling.rs
+++ b/zcash_primitives/src/transaction/components/sapling.rs
@@ -192,6 +192,24 @@ impl<A: Authorization> Bundle<A> {
     }
 }
 
+impl DynamicUsage for Bundle<Authorized> {
+    fn dynamic_usage(&self) -> usize {
+        self.shielded_spends.dynamic_usage() + self.shielded_outputs.dynamic_usage()
+    }
+
+    fn dynamic_usage_bounds(&self) -> (usize, Option<usize>) {
+        let bounds = (
+            self.shielded_spends.dynamic_usage_bounds(),
+            self.shielded_outputs.dynamic_usage_bounds(),
+        );
+
+        (
+            bounds.0 .0 + bounds.1 .0,
+            bounds.0 .1.zip(bounds.1 .1).map(|(a, b)| a + b),
+        )
+    }
+}
+
 #[derive(Clone)]
 pub struct SpendDescription<A: Authorization> {
     cv: ValueCommitment,
@@ -263,6 +281,16 @@ impl<A: Authorization> SpendDescription<A> {
     }
 }
 
+impl DynamicUsage for SpendDescription<Authorized> {
+    fn dynamic_usage(&self) -> usize {
+        self.zkproof.dynamic_usage()
+    }
+
+    fn dynamic_usage_bounds(&self) -> (usize, Option<usize>) {
+        self.zkproof.dynamic_usage_bounds()
+    }
+}
+
 /// Consensus rules (§4.4) & (§4.5):
 /// - Canonical encoding is enforced here.
 /// - "Not small order" is enforced here.