fix(ARRR): store unconfirmed change output (#2276)

mm2src/coins/Cargo.toml

@@ -110,9 +110,9 @@ uuid = { version = "1.2.2", features = ["fast-rng", "serde", "v4"] }
 # We don't need the default web3 features at all since we added our own web3 transport using shared HYPER instance.
 web3 = { git = "https://github.com/KomodoPlatform/rust-web3", tag = "v0.20.0", default-features = false }
 zbase32 = "0.1.2"
-zcash_client_backend = { git = "https://github.com/KomodoPlatform/librustzcash.git", tag = "k-1.4.1" }
-zcash_extras = { git = "https://github.com/KomodoPlatform/librustzcash.git", tag = "k-1.4.1" }
-zcash_primitives =  {features = ["transparent-inputs"], git = "https://github.com/KomodoPlatform/librustzcash.git", tag = "k-1.4.1" }
+zcash_client_backend = { git = "https://github.com/KomodoPlatform/librustzcash.git", tag = "k-1.4.2" }
+zcash_extras = { git = "https://github.com/KomodoPlatform/librustzcash.git", tag = "k-1.4.2" }
+zcash_primitives =  {features = ["transparent-inputs"], git = "https://github.com/KomodoPlatform/librustzcash.git", tag = "k-1.4.2" }
 
 [target.'cfg(target_arch = "wasm32")'.dependencies]
 blake2b_simd = "0.5"
@@ -132,7 +132,7 @@ wasm-bindgen = "0.2.86"
 wasm-bindgen-futures = { version = "0.4.1" }
 wasm-bindgen-test = { version = "0.3.2" }
 web-sys = { version = "0.3.55", features = ["console", "Headers", "Request", "RequestInit", "RequestMode", "Response", "Window"] }
-zcash_proofs = { git = "https://github.com/KomodoPlatform/librustzcash.git", tag = "k-1.4.1", default-features = false, features = ["local-prover"] }
+zcash_proofs = { git = "https://github.com/KomodoPlatform/librustzcash.git", tag = "k-1.4.2", default-features = false, features = ["local-prover"] }
 
 [target.'cfg(not(target_arch = "wasm32"))'.dependencies]
 dirs = { version = "1" }
@@ -154,8 +154,8 @@ tokio = { version = "1.20" }
 tokio-rustls = { version = "0.24" }
 tonic = { version = "0.10", features = ["tls", "tls-webpki-roots", "gzip"] }
 webpki-roots = { version = "0.25" }
-zcash_client_sqlite = { git = "https://github.com/KomodoPlatform/librustzcash.git", tag = "k-1.4.1" }
-zcash_proofs = { git = "https://github.com/KomodoPlatform/librustzcash.git", tag = "k-1.4.1", default-features = false, features = ["local-prover", "multicore"] }
+zcash_client_sqlite = { git = "https://github.com/KomodoPlatform/librustzcash.git", tag = "k-1.4.2" }
+zcash_proofs = { git = "https://github.com/KomodoPlatform/librustzcash.git", tag = "k-1.4.2", default-features = false, features = ["local-prover", "multicore"] }
 
 [target.'cfg(windows)'.dependencies]
 winapi = "0.3"

mm2src/coins/z_coin.rs

@@ -93,6 +93,8 @@ use zcash_primitives::{constants::mainnet as z_mainnet_constants, sapling::Payme
                        zip32::ExtendedFullViewingKey, zip32::ExtendedSpendingKey};
 use zcash_proofs::prover::LocalTxProver;
 
+use self::storage::store_change_output;
+
 cfg_native!(
     use common::{async_blocking, sha256_digest};
     use zcash_client_sqlite::error::SqliteClientError as ZcashClientError;
@@ -208,8 +210,8 @@ pub struct ZCoinFields {
     z_tx_prover: Arc<LocalTxProver>,
     light_wallet_db: WalletDbShared,
     consensus_params: ZcoinConsensusParams,
-    sync_state_connector: AsyncMutex<SaplingSyncConnector>,
     z_balance_event_handler: Option<ZBalanceEventHandler>,
+    sync_state_connector: AsyncMutex<SaplingSyncConnector>,
 }
 
 impl Transaction for ZTransaction {
@@ -474,6 +476,12 @@ impl ZCoin {
                 .await?
                 .tx_result?;
 
+        // Store any change outputs we created in this transaction by decrypting them with our keys
+        // and saving them to the wallet database for future spends
+        store_change_output(self.consensus_params_ref(), &self.z_fields.light_wallet_db, &tx)
+            .await
+            .map_to_mm(GenTxError::SaveChangeNotesError)?;
+
         let additional_data = AdditionalTxData {
             received_by_me,
             spent_by_me: sat_from_big_decimal(&total_input_amount, self.decimals())?,

mm2src/coins/z_coin/storage.rs

@@ -9,6 +9,8 @@ pub mod walletdb;
 pub(crate) use z_params::ZcashParamsWasmImpl;
 
 pub use walletdb::*;
+use zcash_extras::wallet::decrypt_and_store_transaction;
+use zcash_primitives::transaction::Transaction;
 
 use crate::z_coin::z_balance_streaming::ZBalanceEventSender;
 use mm2_err_handle::mm_error::MmResult;
@@ -190,3 +192,18 @@ pub async fn scan_cached_block(
     // If there are any transactions in the block, return the transaction count
     Ok(txs.len())
 }
+
+/// Processes and stores any change outputs created in the transaction by:
+/// - Decrypting outputs using wallet viewing keys
+/// - Adding decrypted change notes to the wallet database
+/// - Making change notes available for future spends
+pub(crate) async fn store_change_output(
+    params: &ZcoinConsensusParams,
+    shared_db: &WalletDbShared,
+    tx: &Transaction,
+) -> Result<(), String> {
+    let mut data = try_s!(shared_db.db.get_update_ops());
+    try_s!(decrypt_and_store_transaction(params, &mut data, tx).await);
+
+    Ok(())
+}

mm2src/coins/z_coin/z_coin_errors.rs

@@ -129,8 +129,8 @@ pub enum GenTxError {
     LightClientErr(String),
     FailedToCreateNote,
     SpendableNotesError(String),
-    #[cfg(target_arch = "wasm32")]
     Internal(String),
+    SaveChangeNotesError(String),
 }
 
 impl From<GetUnspentWitnessErr> for GenTxError {
@@ -177,9 +177,9 @@ impl From<GenTxError> for WithdrawError {
             | GenTxError::BlockchainScanStopped
             | GenTxError::LightClientErr(_)
             | GenTxError::SpendableNotesError(_)
-            | GenTxError::FailedToCreateNote => WithdrawError::InternalError(gen_tx.to_string()),
-            #[cfg(target_arch = "wasm32")]
-            GenTxError::Internal(_) => WithdrawError::InternalError(gen_tx.to_string()),
+            | GenTxError::FailedToCreateNote
+            | GenTxError::Internal(_)
+            | GenTxError::SaveChangeNotesError(_) => WithdrawError::InternalError(gen_tx.to_string()),
         }
     }
 }

mm2src/coins/z_coin/z_htlc.rs

@@ -5,6 +5,7 @@
 // taker payment spend - https://zombie.explorer.lordofthechains.com/tx/af6bb0f99f9a5a070a0c1f53d69e4189b0e9b68f9d66e69f201a6b6d9f93897e
 // maker payment spend - https://rick.explorer.dexstats.info/tx/6a2dcc866ad75cebecb780a02320073a88bcf5e57ddccbe2657494e7747d591e
 
+use super::storage::store_change_output;
 use super::{GenTxError, ZCoin};
 use crate::utxo::rpc_clients::{UtxoRpcClientEnum, UtxoRpcError};
 use crate::utxo::utxo_common::payment_script;
@@ -190,6 +191,12 @@ pub async fn z_p2sh_spend(
     let mut tx_buffer = Vec::with_capacity(1024);
     zcash_tx.write(&mut tx_buffer)?;
 
+    // Store any change outputs we created in this transaction by decrypting them with our keys
+    // and saving them to the wallet database for future spends
+    store_change_output(coin.consensus_params_ref(), &coin.z_fields.light_wallet_db, &zcash_tx)
+        .await
+        .map_to_mm(|err| ZP2SHSpendError::GenTxError(GenTxError::SaveChangeNotesError(err)))?;
+
     coin.utxo_rpc_client()
         .send_raw_transaction(tx_buffer.into())
         .compat()