Merge branch 'brent/delegation-validators' (#3043)

* origin/brent/delegation-validators:
  better comment
  use unslashed bond amounts in `find_delegations`
  fix from comments
  changelog: add #3043
  prune old `prev_ranges` data
  fix edge case (fully unbond then rebond)
  fixes from review comments
  fix and finish test
  new approach
  don't merklize delegation targets
  improve nomenclature and comments
  rename and fix rpc fns to get delegator's target validators
  track all validators to which an account has bonded tokens

.changelog/unreleased/improvements/3043-delegation-validators.md

@@ -0,0 +1,3 @@
+- Optimize the finding of validators to which a delegator has bonds at a
+  given epoch. Now keeps data in storage rather than iterating over all bonds.
+  ([\#3043](https://github.com/anoma/namada/pull/3043))

crates/apps/src/lib/client/rpc.rs

@@ -2412,13 +2412,19 @@ pub async fn query_delegations<N: Namada>(
     let delegations: HashSet<Address> = unwrap_client_response::<N::Client, _>(
         RPC.vp()
             .pos()
-            .delegation_validators(context.client(), &owner)
+            .delegation_validators(context.client(), &owner, &None)
             .await,
     );
     if delegations.is_empty() {
-        display_line!(context.io(), "No delegations found");
+        display_line!(
+            context.io(),
+            "No delegations found active in the current epoch"
+        );
     } else {
-        display_line!(context.io(), "Found delegations to:");
+        display_line!(
+            context.io(),
+            "Found delegations in the current epoch to:"
+        );
         for delegation in delegations {
             display_line!(context.io(), "  {delegation}");
         }
@@ -2823,25 +2829,26 @@ async fn get_validator_stake<C: namada::ledger::queries::Client + Sync>(
     )
 }
 
-pub async fn get_delegators_delegation<
+pub async fn get_delegation_validators<
     C: namada::ledger::queries::Client + Sync,
 >(
     client: &C,
     address: &Address,
 ) -> HashSet<Address> {
-    namada_sdk::rpc::get_delegators_delegation(client, address)
+    let epoch = namada_sdk::rpc::query_epoch(client).await.unwrap();
+    namada_sdk::rpc::get_delegation_validators(client, address, epoch)
         .await
         .unwrap()
 }
 
-pub async fn get_delegators_delegation_at<
+pub async fn get_delegations_of_delegator_at<
     C: namada::ledger::queries::Client + Sync,
 >(
     client: &C,
     address: &Address,
     epoch: Epoch,
 ) -> HashMap<Address, token::Amount> {
-    namada_sdk::rpc::get_delegators_delegation_at(client, address, epoch)
+    namada_sdk::rpc::get_delegations_of_delegator_at(client, address, epoch)
         .await
         .unwrap()
 }

crates/apps/src/lib/node/ledger/shell/finalize_block.rs

@@ -1283,7 +1283,7 @@ mod test_finalize_block {
                 id: proposal_id,
                 vote,
                 voter: validator,
-                delegations: vec![],
+                delegation_validators: vec![],
             };
             // Vote to accept the proposal (there's only one validator, so its
             // vote decides)

crates/apps/src/lib/node/ledger/shell/mod.rs

@@ -357,7 +357,8 @@ pub fn is_merklized_storage_key(key: &namada_sdk::storage::Key) -> bool {
         && *key != token::storage_key::masp_convert_anchor_key()
         && *key != token::storage_key::masp_token_map_key()
         && *key != token::storage_key::masp_assets_hash_key()
-        || namada::ibc::storage::is_ibc_counter_key(key))
+        || namada::ibc::storage::is_ibc_counter_key(key)
+        || namada::proof_of_stake::storage_key::is_delegation_targets_key(key))
 }
 
 /// Channels for communicating with an Ethereum oracle.

crates/benches/native_vps.rs

@@ -89,7 +89,9 @@ fn governance(c: &mut Criterion) {
                         id: 0,
                         vote: ProposalVote::Yay,
                         voter: defaults::albert_address(),
-                        delegations: vec![defaults::validator_address()],
+                        delegation_validators: vec![
+                            defaults::validator_address(),
+                        ],
                     },
                     None,
                     None,
@@ -105,7 +107,7 @@ fn governance(c: &mut Criterion) {
                         id: 0,
                         vote: ProposalVote::Nay,
                         voter: defaults::validator_address(),
-                        delegations: vec![],
+                        delegation_validators: vec![],
                     },
                     None,
                     None,

crates/benches/txs.rs

@@ -547,7 +547,7 @@ fn vote_proposal(c: &mut Criterion) {
             id: 0,
             vote: ProposalVote::Yay,
             voter: defaults::albert_address(),
-            delegations: vec![defaults::validator_address()],
+            delegation_validators: vec![defaults::validator_address()],
         },
         None,
         None,
@@ -560,7 +560,7 @@ fn vote_proposal(c: &mut Criterion) {
             id: 0,
             vote: ProposalVote::Nay,
             voter: defaults::validator_address(),
-            delegations: vec![],
+            delegation_validators: vec![],
         },
         None,
         None,

crates/benches/vps.rs

@@ -94,8 +94,9 @@ fn vp_implicit(c: &mut Criterion) {
             id: 0,
             vote: ProposalVote::Yay,
             voter: Address::from(&implicit_account.to_public()),
-            delegations: vec![], /* NOTE: no need to bond tokens because the
-                                  * implicit vp doesn't check that */
+            delegation_validators: vec![], /* NOTE: no need to bond tokens
+                                            * because the
+                                            * implicit vp doesn't check that */
         },
         None,
         None,
@@ -251,7 +252,7 @@ fn vp_user(c: &mut Criterion) {
             id: 0,
             vote: ProposalVote::Yay,
             voter: defaults::validator_address(),
-            delegations: vec![],
+            delegation_validators: vec![],
         },
         None,
         None,

crates/governance/src/storage/keys.rs

@@ -442,10 +442,10 @@ pub fn get_proposal_vote_prefix_key(id: u64) -> Key {
 pub fn get_vote_proposal_key(
     id: u64,
     voter_address: Address,
-    delegation_address: Address,
+    validator_address: Address,
 ) -> Key {
     get_proposal_vote_prefix_key(id)
-        .push(&delegation_address)
+        .push(&validator_address)
         .expect("Cannot obtain a storage key")
         .push(&voter_address)
         .expect("Cannot obtain a storage key")

crates/governance/src/storage/mod.rs

@@ -103,11 +103,11 @@ pub fn vote_proposal<S>(storage: &mut S, data: VoteProposalData) -> Result<()>
 where
     S: StorageRead + StorageWrite,
 {
-    for delegation in data.delegations {
+    for validator in data.delegation_validators {
         let vote_key = governance_keys::get_vote_proposal_key(
             data.id,
             data.voter.clone(),
-            delegation,
+            validator,
         );
         storage.write(&vote_key, data.vote.clone())?;
     }

crates/governance/src/storage/proposal.rs

@@ -83,7 +83,7 @@ pub struct VoteProposalData {
     /// The proposal voter address
     pub voter: Address,
     /// Validators to who the voter has delegations to
-    pub delegations: Vec<Address>,
+    pub delegation_validators: Vec<Address>,
 }
 
 impl TryFrom<DefaultProposal> for InitProposalData {
@@ -770,13 +770,13 @@ pub mod testing {
             id: u64,
             vote in arb_proposal_vote(),
             voter in arb_non_internal_address(),
-            delegations in collection::vec(arb_non_internal_address(), 0..10),
+            delegation_validators in collection::vec(arb_non_internal_address(), 0..10),
         ) -> VoteProposalData {
             VoteProposalData {
                 id,
                 vote,
                 voter,
-                delegations,
+                delegation_validators,
             }
         }
     }

crates/light_sdk/src/reading/asynchronous/pos.rs

@@ -154,7 +154,7 @@ pub async fn get_validator_state(
 }
 
 /// Get the delegator's delegation
-pub async fn get_delegators_delegation(
+pub async fn get_delegation_validators(
     tendermint_addr: &str,
     address: &Address,
 ) -> Result<HashSet<Address>, Error> {
@@ -163,11 +163,12 @@ pub async fn get_delegators_delegation(
             .map_err(|e| Error::Other(e.to_string()))?,
     )
     .map_err(|e| Error::Other(e.to_string()))?;
-    rpc::get_delegators_delegation(&client, address).await
+    let epoch = rpc::query_epoch(&client).await?;
+    rpc::get_delegation_validators(&client, address, epoch).await
 }
 
 /// Get the delegator's delegation at some epoh
-pub async fn get_delegators_delegation_at(
+pub async fn get_delegations_of_delegator_at(
     tendermint_addr: &str,
     address: &Address,
     epoch: Epoch,
@@ -177,7 +178,7 @@ pub async fn get_delegators_delegation_at(
             .map_err(|e| Error::Other(e.to_string()))?,
     )
     .map_err(|e| Error::Other(e.to_string()))?;
-    rpc::get_delegators_delegation_at(&client, address, epoch).await
+    rpc::get_delegations_of_delegator_at(&client, address, epoch).await
 }
 
 /// Query and return validator's commission rate and max commission rate

crates/light_sdk/src/reading/blocking/pos.rs

@@ -165,7 +165,7 @@ pub fn get_validator_state(
 }
 
 /// Get the delegator's delegation
-pub fn get_delegators_delegation(
+pub fn get_delegation_validators(
     tendermint_addr: &str,
     address: &Address,
 ) -> Result<HashSet<Address>, Error> {
@@ -175,11 +175,12 @@ pub fn get_delegators_delegation(
     )
     .map_err(|e| Error::Other(e.to_string()))?;
     let rt = Runtime::new().unwrap();
-    rt.block_on(rpc::get_delegators_delegation(&client, address))
+    let epoch = rpc::query_epoch(&client).await?;
+    rt.block_on(rpc::get_delegation_validators(&client, address, epoch))
 }
 
 /// Get the delegator's delegation at some epoh
-pub fn get_delegators_delegation_at(
+pub fn get_delegations_of_delegator_at(
     tendermint_addr: &str,
     address: &Address,
     epoch: Epoch,
@@ -190,7 +191,9 @@ pub fn get_delegators_delegation_at(
     )
     .map_err(|e| Error::Other(e.to_string()))?;
     let rt = Runtime::new().unwrap();
-    rt.block_on(rpc::get_delegators_delegation_at(&client, address, epoch))
+    rt.block_on(rpc::get_delegations_of_delegator_at(
+        &client, address, epoch,
+    ))
 }
 
 /// Query and return validator's commission rate and max commission rate

crates/light_sdk/src/transaction/governance.rs

@@ -113,7 +113,7 @@ impl VoteProposal {
             id,
             vote,
             voter,
-            delegations,
+            delegation_validators: delegations,
         };
 
         Self(transaction::build_tx(