From e746f7b6f9b7f9e01104b58f24fc43c1f4a622e3 Mon Sep 17 00:00:00 2001
From: Jack Grigg <jack@z.cash>
Date: Thu, 24 Jan 2019 23:26:14 +0000
Subject: [PATCH] Add tx index within block to WalletTx struct

---
 zcash_client_backend/src/wallet.rs      |  1 +
 zcash_client_backend/src/welding_rig.rs | 10 +++++++++-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/zcash_client_backend/src/wallet.rs b/zcash_client_backend/src/wallet.rs
index 22df1cb..dd5229b 100644
--- a/zcash_client_backend/src/wallet.rs
+++ b/zcash_client_backend/src/wallet.rs
@@ -13,6 +13,7 @@ use zcash_primitives::{
 /// [`Transaction`]: zcash_primitives::transaction::Transaction
 pub struct WalletTx {
     pub txid: TxId,
+    pub index: usize,
     pub num_spends: usize,
     pub num_outputs: usize,
     pub shielded_spends: Vec<WalletShieldedSpend>,
diff --git a/zcash_client_backend/src/welding_rig.rs b/zcash_client_backend/src/welding_rig.rs
index b8310e3..27d29bb 100644
--- a/zcash_client_backend/src/welding_rig.rs
+++ b/zcash_client_backend/src/welding_rig.rs
@@ -162,6 +162,7 @@ pub fn scan_block(
             wtxs.push((
                 WalletTx {
                     txid,
+                    index: tx.index as usize,
                     num_spends,
                     num_outputs,
                     shielded_spends,
@@ -269,7 +270,11 @@ mod tests {
         cb.set_height(height as u64);
 
         // Add a random Sapling tx before ours
-        cb.vtx.push(random_compact_tx(&mut rng));
+        {
+            let mut tx = random_compact_tx(&mut rng);
+            tx.index = cb.vtx.len() as u64;
+            cb.vtx.push(tx);
+        }
 
         let mut cspend = CompactSpend::new();
         cspend.set_nf(nf.to_vec());
@@ -283,6 +288,7 @@ mod tests {
         ctx.set_hash(txid);
         ctx.spends.push(cspend);
         ctx.outputs.push(cout);
+        ctx.index = cb.vtx.len() as u64;
         cb.vtx.push(ctx);
 
         cb
@@ -301,6 +307,7 @@ mod tests {
         assert_eq!(txs.len(), 1);
 
         let (tx, new_witnesses) = &txs[0];
+        assert_eq!(tx.index, 1);
         assert_eq!(tx.num_spends, 1);
         assert_eq!(tx.num_outputs, 1);
         assert_eq!(tx.shielded_spends.len(), 0);
@@ -329,6 +336,7 @@ mod tests {
         assert_eq!(txs.len(), 1);
 
         let (tx, new_witnesses) = &txs[0];
+        assert_eq!(tx.index, 1);
         assert_eq!(tx.num_spends, 1);
         assert_eq!(tx.num_outputs, 1);
         assert_eq!(tx.shielded_spends.len(), 1);