zcash_client_backend: Move test-only methods to new `WalletTest` trait

This reduces the feature-flag-related `WalletRead` breakage for crate
users, and gives us a place to expose even more internal Data Access API
implementation details for general testing purposes.

zcash_client_backend/src/data_api.rs

@@ -1166,13 +1166,20 @@ pub trait WalletRead {
     /// transaction data requests, such as when it is necessary to fill in purely-transparent
     /// transaction history by walking the chain backwards via transparent inputs.
     fn transaction_data_requests(&self) -> Result<Vec<TransactionDataRequest>, Self::Error>;
+}
 
+/// Read-only operations required for testing light wallet functions.
+///
+/// These methods expose internal details or unstable interfaces, primarily to enable use
+/// of the [`testing`] framework. They should not be used in production software.
+#[cfg(any(test, feature = "test-dependencies"))]
+#[delegatable_trait]
+pub trait WalletTest: WalletRead {
     /// Returns a vector of transaction summaries.
     ///
     /// Currently test-only, as production use could return a very large number of results; either
     /// pagination or a streaming design will be necessary to stabilize this feature for production
     /// use.
-    #[cfg(any(test, feature = "test-dependencies"))]
     fn get_tx_history(
         &self,
     ) -> Result<Vec<testing::TransactionSummary<Self::AccountId>>, Self::Error> {
@@ -1181,7 +1188,6 @@ pub trait WalletRead {
 
     /// Returns the note IDs for shielded notes sent by the wallet in a particular
     /// transaction.
-    #[cfg(any(test, feature = "test-dependencies"))]
     fn get_sent_note_ids(
         &self,
         _txid: &TxId,

zcash_client_backend/src/data_api/testing.rs

@@ -56,6 +56,7 @@ use crate::{
     ShieldedProtocol,
 };
 
+use super::WalletTest;
 #[allow(deprecated)]
 use super::{
     chain::{scan_cached_blocks, BlockSource, ChainState, CommitmentTreeRoot, ScanSummary},
@@ -319,14 +320,14 @@ impl<A: Account> Account for TestAccount<A> {
     }
 }
 
-pub trait Reset: WalletRead + Sized {
+pub trait Reset: WalletTest + Sized {
     type Handle;
 
     fn reset<C>(st: &mut TestState<C, Self, LocalNetwork>) -> Self::Handle;
 }
 
 /// The state for a `zcash_client_sqlite` test.
-pub struct TestState<Cache, DataStore: WalletRead, Network> {
+pub struct TestState<Cache, DataStore: WalletTest, Network> {
     cache: Cache,
     cached_blocks: BTreeMap<BlockHeight, CachedBlock>,
     latest_block_height: Option<BlockHeight>,
@@ -336,7 +337,7 @@ pub struct TestState<Cache, DataStore: WalletRead, Network> {
     rng: ChaChaRng,
 }
 
-impl<Cache, DataStore: WalletRead, Network> TestState<Cache, DataStore, Network> {
+impl<Cache, DataStore: WalletTest, Network> TestState<Cache, DataStore, Network> {
     /// Exposes an immutable reference to the test's `DataStore`.
     pub fn wallet(&self) -> &DataStore {
         &self.wallet_data
@@ -358,7 +359,7 @@ impl<Cache, DataStore: WalletRead, Network> TestState<Cache, DataStore, Network>
     }
 }
 
-impl<Cache, DataStore: WalletRead, Network: consensus::Parameters>
+impl<Cache, DataStore: WalletTest, Network: consensus::Parameters>
     TestState<Cache, DataStore, Network>
 {
     /// Convenience method for obtaining the Sapling activation height for the network under test.
@@ -405,7 +406,7 @@ impl<Cache, DataStore: WalletRead, Network: consensus::Parameters>
 impl<Cache: TestCache, DataStore, Network> TestState<Cache, DataStore, Network>
 where
     Network: consensus::Parameters,
-    DataStore: WalletWrite,
+    DataStore: WalletTest + WalletWrite,
     <Cache::BlockSource as BlockSource>::Error: fmt::Debug,
 {
     /// Exposes an immutable reference to the test's [`BlockSource`].
@@ -697,7 +698,7 @@ where
     Cache: TestCache,
     <Cache::BlockSource as BlockSource>::Error: fmt::Debug,
     ParamsT: consensus::Parameters + Send + 'static,
-    DbT: InputSource + WalletWrite + WalletCommitmentTrees,
+    DbT: InputSource + WalletTest + WalletWrite + WalletCommitmentTrees,
     <DbT as WalletRead>::AccountId: ConditionallySelectable + Default + Send + 'static,
 {
     /// Invokes [`scan_cached_blocks`] with the given arguments, expecting success.
@@ -760,6 +761,7 @@ where
     AccountIdT: std::cmp::Eq + std::hash::Hash,
     ErrT: std::fmt::Debug,
     DbT: InputSource<AccountId = AccountIdT, Error = ErrT>
+        + WalletTest
         + WalletWrite<AccountId = AccountIdT, Error = ErrT>
         + WalletCommitmentTrees,
     <DbT as WalletRead>::AccountId: ConditionallySelectable + Default + Send + 'static,
@@ -1069,7 +1071,19 @@ where
     pub fn get_wallet_summary(&self, min_confirmations: u32) -> Option<WalletSummary<AccountIdT>> {
         self.wallet().get_wallet_summary(min_confirmations).unwrap()
     }
+}
 
+impl<Cache, DbT, ParamsT, AccountIdT, ErrT> TestState<Cache, DbT, ParamsT>
+where
+    ParamsT: consensus::Parameters + Send + 'static,
+    AccountIdT: std::cmp::Eq + std::hash::Hash,
+    ErrT: std::fmt::Debug,
+    DbT: InputSource<AccountId = AccountIdT, Error = ErrT>
+        + WalletTest
+        + WalletWrite<AccountId = AccountIdT, Error = ErrT>
+        + WalletCommitmentTrees,
+    <DbT as WalletRead>::AccountId: ConditionallySelectable + Default + Send + 'static,
+{
     /// Returns a transaction from the history.
     #[allow(dead_code)]
     pub fn get_tx_from_history(
@@ -1149,6 +1163,7 @@ pub trait DataStoreFactory {
     type DsError: core::fmt::Debug;
     type DataStore: InputSource<AccountId = Self::AccountId, Error = Self::DsError>
         + WalletRead<AccountId = Self::AccountId, Account = Self::Account, Error = Self::DsError>
+        + WalletTest
         + WalletWrite
         + WalletCommitmentTrees;
 

zcash_client_backend/src/data_api/testing/orchard.rs

@@ -25,7 +25,7 @@ use crate::{
     data_api::{
         chain::{CommitmentTreeRoot, ScanSummary},
         testing::{pool::ShieldedPoolTester, TestState},
-        DecryptedTransaction, InputSource, WalletCommitmentTrees, WalletRead, WalletSummary,
+        DecryptedTransaction, InputSource, WalletCommitmentTrees, WalletSummary, WalletTest,
     },
     wallet::{Note, ReceivedNote},
 };
@@ -40,7 +40,7 @@ impl ShieldedPoolTester for OrchardPoolTester {
     type MerkleTreeHash = MerkleHashOrchard;
     type Note = orchard::note::Note;
 
-    fn test_account_fvk<Cache, DbT: WalletRead, P: consensus::Parameters>(
+    fn test_account_fvk<Cache, DbT: WalletTest, P: consensus::Parameters>(
         st: &TestState<Cache, DbT, P>,
     ) -> Self::Fvk {
         st.test_account_orchard().unwrap().clone()
@@ -90,7 +90,7 @@ impl ShieldedPoolTester for OrchardPoolTester {
         MerkleHashOrchard::empty_root(level)
     }
 
-    fn put_subtree_roots<Cache, DbT: WalletRead + WalletCommitmentTrees, P>(
+    fn put_subtree_roots<Cache, DbT: WalletTest + WalletCommitmentTrees, P>(
         st: &mut TestState<Cache, DbT, P>,
         start_index: u64,
         roots: &[CommitmentTreeRoot<Self::MerkleTreeHash>],
@@ -103,7 +103,7 @@ impl ShieldedPoolTester for OrchardPoolTester {
         s.next_orchard_subtree_index()
     }
 
-    fn select_spendable_notes<Cache, DbT: InputSource + WalletRead, P>(
+    fn select_spendable_notes<Cache, DbT: InputSource + WalletTest, P>(
         st: &TestState<Cache, DbT, P>,
         account: <DbT as InputSource>::AccountId,
         target_value: Zatoshis,

zcash_client_backend/src/data_api/testing/pool.rs

@@ -23,7 +23,7 @@ use crate::{
         testing::{AddressType, TestBuilder},
         wallet::{decrypt_and_store_transaction, input_selection::GreedyInputSelector},
         Account as _, DecryptedTransaction, InputSource, WalletCommitmentTrees, WalletRead,
-        WalletSummary,
+        WalletSummary, WalletTest,
     },
     decrypt_transaction,
     fees::{standard, DustOutputPolicy},
@@ -42,7 +42,7 @@ pub trait ShieldedPoolTester {
     type MerkleTreeHash;
     type Note;
 
-    fn test_account_fvk<Cache, DbT: WalletRead, P: consensus::Parameters>(
+    fn test_account_fvk<Cache, DbT: WalletTest, P: consensus::Parameters>(
         st: &TestState<Cache, DbT, P>,
     ) -> Self::Fvk;
     fn usk_to_sk(usk: &UnifiedSpendingKey) -> &Self::Sk;
@@ -68,7 +68,7 @@ pub trait ShieldedPoolTester {
     fn empty_tree_leaf() -> Self::MerkleTreeHash;
     fn empty_tree_root(level: Level) -> Self::MerkleTreeHash;
 
-    fn put_subtree_roots<Cache, DbT: WalletRead + WalletCommitmentTrees, P>(
+    fn put_subtree_roots<Cache, DbT: WalletTest + WalletCommitmentTrees, P>(
         st: &mut TestState<Cache, DbT, P>,
         start_index: u64,
         roots: &[CommitmentTreeRoot<Self::MerkleTreeHash>],
@@ -77,7 +77,7 @@ pub trait ShieldedPoolTester {
     fn next_subtree_index<A: Hash + Eq>(s: &WalletSummary<A>) -> u64;
 
     #[allow(clippy::type_complexity)]
-    fn select_spendable_notes<Cache, DbT: InputSource + WalletRead, P>(
+    fn select_spendable_notes<Cache, DbT: InputSource + WalletTest, P>(
         st: &TestState<Cache, DbT, P>,
         account: <DbT as InputSource>::AccountId,
         target_value: Zatoshis,

zcash_client_backend/src/data_api/testing/sapling.rs

@@ -19,7 +19,7 @@ use zip32::Scope;
 use crate::{
     data_api::{
         chain::{CommitmentTreeRoot, ScanSummary},
-        DecryptedTransaction, InputSource, WalletCommitmentTrees, WalletRead, WalletSummary,
+        DecryptedTransaction, InputSource, WalletCommitmentTrees, WalletSummary, WalletTest,
     },
     wallet::{Note, ReceivedNote},
 };
@@ -36,7 +36,7 @@ impl ShieldedPoolTester for SaplingPoolTester {
     type MerkleTreeHash = sapling::Node;
     type Note = sapling::Note;
 
-    fn test_account_fvk<Cache, DbT: WalletRead, P: consensus::Parameters>(
+    fn test_account_fvk<Cache, DbT: WalletTest, P: consensus::Parameters>(
         st: &TestState<Cache, DbT, P>,
     ) -> Self::Fvk {
         st.test_account_sapling().unwrap().clone()
@@ -74,7 +74,7 @@ impl ShieldedPoolTester for SaplingPoolTester {
         ::sapling::Node::empty_root(level)
     }
 
-    fn put_subtree_roots<Cache, DbT: WalletRead + WalletCommitmentTrees, P>(
+    fn put_subtree_roots<Cache, DbT: WalletTest + WalletCommitmentTrees, P>(
         st: &mut TestState<Cache, DbT, P>,
         start_index: u64,
         roots: &[CommitmentTreeRoot<Self::MerkleTreeHash>],
@@ -87,7 +87,7 @@ impl ShieldedPoolTester for SaplingPoolTester {
         s.next_sapling_subtree_index()
     }
 
-    fn select_spendable_notes<Cache, DbT: InputSource + WalletRead, P>(
+    fn select_spendable_notes<Cache, DbT: InputSource + WalletTest, P>(
         st: &TestState<Cache, DbT, P>,
         account: <DbT as InputSource>::AccountId,
         target_value: Zatoshis,

zcash_client_sqlite/src/lib.rs

@@ -53,7 +53,7 @@ use zcash_client_backend::{
         Account, AccountBirthday, AccountPurpose, AccountSource, BlockMetadata,
         DecryptedTransaction, InputSource, NullifierQuery, ScannedBlock, SeedRelevance,
         SentTransaction, SpendableNotes, TransactionDataRequest, WalletCommitmentTrees, WalletRead,
-        WalletSummary, WalletWrite, SAPLING_SHARD_HEIGHT,
+        WalletSummary, WalletTest, WalletWrite, SAPLING_SHARD_HEIGHT,
     },
     keys::{
         AddressGenerationError, UnifiedAddressRequest, UnifiedFullViewingKey, UnifiedSpendingKey,
@@ -614,13 +614,14 @@ impl<C: Borrow<rusqlite::Connection>, P: consensus::Parameters> WalletRead for W
 
         Ok(iter.collect())
     }
+}
 
-    #[cfg(any(test, feature = "test-dependencies"))]
+#[cfg(any(test, feature = "test-dependencies"))]
+impl<C: Borrow<rusqlite::Connection>, P: consensus::Parameters> WalletTest for WalletDb<C, P> {
     fn get_tx_history(&self) -> Result<Vec<TransactionSummary<Self::AccountId>>, Self::Error> {
         wallet::testing::get_tx_history(self.conn.borrow())
     }
 
-    #[cfg(any(test, feature = "test-dependencies"))]
     fn get_sent_note_ids(
         &self,
         txid: &TxId,
@@ -1725,7 +1726,8 @@ mod tests {
     use zcash_client_backend::data_api::{
         chain::ChainState,
         testing::{TestBuilder, TestState},
-        Account, AccountBirthday, AccountPurpose, AccountSource, WalletRead, WalletWrite,
+        Account, AccountBirthday, AccountPurpose, AccountSource, WalletRead, WalletTest,
+        WalletWrite,
     };
     use zcash_keys::keys::{UnifiedFullViewingKey, UnifiedSpendingKey};
     use zcash_primitives::block::BlockHash;
@@ -1837,7 +1839,7 @@ mod tests {
             AccountSource::Derived { seed_fingerprint: _, account_index } if account_index == zip32_index_2);
     }
 
-    fn check_collisions<C, DbT: WalletWrite, P: consensus::Parameters>(
+    fn check_collisions<C, DbT: WalletTest + WalletWrite, P: consensus::Parameters>(
         st: &mut TestState<C, DbT, P>,
         ufvk: &UnifiedFullViewingKey,
         birthday: &AccountBirthday,

zcash_client_sqlite/src/testing/db.rs

@@ -43,6 +43,7 @@ use {
 #[derive(Delegate)]
 #[delegate(InputSource, target = "wallet_db")]
 #[delegate(WalletRead, target = "wallet_db")]
+#[delegate(WalletTest, target = "wallet_db")]
 #[delegate(WalletWrite, target = "wallet_db")]
 #[delegate(WalletCommitmentTrees, target = "wallet_db")]
 pub(crate) struct TestDb {

zcash_client_sqlite/src/testing/pool.rs

@@ -100,7 +100,7 @@ pub(crate) fn send_multi_step_proposed_transfer<T: ShieldedPoolTester>() {
 
     use rand_core::OsRng;
     use zcash_client_backend::{
-        data_api::{TransactionDataRequest, TransactionStatus},
+        data_api::{TransactionDataRequest, TransactionStatus, WalletTest},
         fees::ChangeValue,
         wallet::TransparentAddressMetadata,
     };