Merge pull request #39 from aave/mike/improve/263

feat(pool_token_logic): transfer out remaining balance of underlying token when drop_reserve

Author: mpsc0x

aave-core/sources/aave-periphery/collector.move

@@ -137,4 +137,12 @@ module aave_pool::collector {
     public fun get_collector_name(): vector<u8> {
         COLLECTOR_NAME
     }
+
+    #[test_only]
+    /// @notice Returns the collector resource account signer for testing
+    public fun get_collector_account_with_signer(): signer acquires CollectorData {
+        // derive resource account signer
+        let collector_data = borrow_global<CollectorData>(@aave_pool);
+        account::create_signer_with_capability(&collector_data.resource_account)
+    }
 }

aave-core/sources/aave-pool/pool_token_logic.move

@@ -302,6 +302,26 @@ module aave_pool::pool_token_logic {
             error_config::get_eunderlying_claimable_rights_not_zero()
         );
 
+        // Check for remaining underlying assets in the resource account and transfer to treasury
+        let remaining_underlying_balance =
+            fungible_asset_manager::balance_of(
+                a_token_factory::get_token_account_address(a_token_address),
+                asset
+            );
+
+        if (remaining_underlying_balance > 0) {
+            // Get treasury address from aToken
+            let treasury_address =
+                a_token_factory::get_reserve_treasury_address(a_token_address);
+
+            // Transfer remaining underlying assets to treasury using a_token_factory
+            a_token_factory::transfer_underlying_to(
+                treasury_address,
+                (remaining_underlying_balance as u256),
+                a_token_address
+            );
+        };
+
         // Remove the ReserveList from the smart table
         let active_reserve_count = pool::number_of_active_reserves();
         pool::delete_reserve_data(asset);