⚡️ [API-2349] Preserve Pre Swap Out Asset Contract Balance (#83)

* add admin address to deploy script configs

* reformat / fix lints to clean up script

* add admin param to instantiate/instantiate2 msgs

* bump contract versions to 0.3.0

* set contract version in entrypoint

* add contract version to ibc adapter contracts

* add contract version to swap adapter contracts

* remove unused python import

* remove another unused import in python

* add migrate message to entry point contract

* run make fmt

* add migrate msg to adapter contract

* run make schema

* use correct var name

* run make upgrade

* run make update

* update neutron sdk to 0.8

* update deps, remove deprecated functions, update tests after upgrade

* limit out asset to only what is obtained from the swap

* update existing tests with pre swap amount 0

* add test ensuring pre swap out asset contract balance preserved

* ensure PRE_SWAP_OUT_ASSET_AMOUNT is set properly in unit test

* run make fmt

* tidy

contracts/entry-point/src/execute.rs

@@ -4,8 +4,8 @@ use crate::{
     error::{ContractError, ContractResult},
     reply::{RecoverTempStorage, RECOVER_REPLY_ID},
     state::{
-        BLOCKED_CONTRACT_ADDRESSES, IBC_TRANSFER_CONTRACT_ADDRESS, RECOVER_TEMP_STORAGE,
-        SWAP_VENUE_MAP,
+        BLOCKED_CONTRACT_ADDRESSES, IBC_TRANSFER_CONTRACT_ADDRESS, PRE_SWAP_OUT_ASSET_AMOUNT,
+        RECOVER_TEMP_STORAGE, SWAP_VENUE_MAP,
     },
 };
 use cosmwasm_std::{
@@ -116,6 +116,11 @@ pub fn execute_swap_and_action(
         return Err(ContractError::Timeout);
     }
 
+    // Save the current out asset amount to storage as the pre swap out asset amount
+    let pre_swap_out_asset_amount =
+        get_current_asset_available(&deps, &env, min_asset.denom())?.amount();
+    PRE_SWAP_OUT_ASSET_AMOUNT.save(deps.storage, &pre_swap_out_asset_amount)?;
+
     // Already validated at entrypoints (both direct and cw20_receive)
     let mut remaining_asset = sent_asset;
 
@@ -432,9 +437,22 @@ pub fn execute_post_swap_action(
     let mut response: Response =
         Response::new().add_attribute("action", "execute_post_swap_action");
 
-    // Get contract balance of min out asset immediately after swap
+    // Get the pre swap out asset amount from storage
+    let pre_swap_out_asset_amount = PRE_SWAP_OUT_ASSET_AMOUNT.load(deps.storage)?;
+
+    // Get contract balance of min out asset post swap
     // for fee deduction and transfer out amount enforcement
-    let transfer_out_asset = get_current_asset_available(&deps, &env, min_asset.denom())?;
+    let post_swap_out_asset = get_current_asset_available(&deps, &env, min_asset.denom())?;
+
+    // Set the transfer out asset to the post swap out asset amount minus the pre swap out asset amount
+    // Since we only want to transfer out the amount received from the swap
+    let transfer_out_asset = Asset::new(
+        deps.api,
+        min_asset.denom(),
+        post_swap_out_asset
+            .amount()
+            .checked_sub(pre_swap_out_asset_amount)?,
+    );
 
     // Error if the contract balance is less than the min asset out amount
     if transfer_out_asset.amount() < min_asset.amount() {

contracts/entry-point/src/state.rs

@@ -1,5 +1,5 @@
 use crate::reply::RecoverTempStorage;
-use cosmwasm_std::Addr;
+use cosmwasm_std::{Addr, Uint128};
 use cw_storage_plus::{Item, Map};
 
 pub const BLOCKED_CONTRACT_ADDRESSES: Map<&Addr, ()> = Map::new("blocked_contract_addresses");
@@ -9,3 +9,8 @@ pub const IBC_TRANSFER_CONTRACT_ADDRESS: Item<Addr> = Item::new("ibc_transfer_co
 // Temporary state to save variables to be used in
 // reply handling in case of recovering from an error
 pub const RECOVER_TEMP_STORAGE: Item<RecoverTempStorage> = Item::new("recover_temp_storage");
+
+// Temporary state to save the amount of the out asset the contract
+// has pre swap so that we can ensure the amount transferred out does not
+// exceed the amount the contract obtained from the current swap/call
+pub const PRE_SWAP_OUT_ASSET_AMOUNT: Item<Uint128> = Item::new("pre_swap_out_asset_amount");

contracts/entry-point/tests/test_execute_post_swap_action.rs

@@ -12,7 +12,7 @@ use skip::{
 };
 use skip_api_entry_point::{
     error::ContractError,
-    state::{BLOCKED_CONTRACT_ADDRESSES, IBC_TRANSFER_CONTRACT_ADDRESS},
+    state::{BLOCKED_CONTRACT_ADDRESSES, IBC_TRANSFER_CONTRACT_ADDRESS, PRE_SWAP_OUT_ASSET_AMOUNT},
 };
 use test_case::test_case;
 
@@ -38,6 +38,9 @@ Expect Response
     - Ibc Transfer w/ IBC Fees of same denom as min coin With Exact Out Set To True
     - Contract Call With Exact Out Set To True
 
+    // Invariants
+    - Pre Swap Out Asset Contract Balance Preserved
+
 Expect Error
     - Transfer Timeout
     - Received Less Native Asset From Swap Than Min Asset
@@ -53,6 +56,7 @@ struct Params {
     min_asset: Asset,
     post_swap_action: Action,
     exact_out: bool,
+    pre_swap_out_asset_amount: Uint128,
     expected_messages: Vec<SubMsg>,
     expected_error: Option<ContractError>,
 }
@@ -66,6 +70,7 @@ struct Params {
             to_address: "cosmos1xv9tklw7d82sezh9haa573wufgy59vmwe6xxe5".to_string(),
         },
         exact_out: true,
+        pre_swap_out_asset_amount: Uint128::new(0),
         expected_messages: vec![SubMsg {
             id: 0,
             msg: BankMsg::Send {
@@ -87,6 +92,7 @@ struct Params {
             to_address: "cosmos1xv9tklw7d82sezh9haa573wufgy59vmwe6xxe5".to_string(),
         },
         exact_out: false,
+        pre_swap_out_asset_amount: Uint128::new(0),
         expected_messages: vec![SubMsg {
             id: 0,
             msg: BankMsg::Send {
@@ -111,6 +117,7 @@ struct Params {
             to_address: "cosmos1xv9tklw7d82sezh9haa573wufgy59vmwe6xxe5".to_string(),
         },
         exact_out: false,
+        pre_swap_out_asset_amount: Uint128::new(0),
         expected_messages: vec![SubMsg {
             id: 0,
             msg: WasmMsg::Execute {
@@ -144,6 +151,7 @@ struct Params {
             fee_swap: None,
         },
         exact_out: false,
+        pre_swap_out_asset_amount: Uint128::new(0),
         expected_messages: vec![SubMsg {
             id: 0,
             msg: WasmMsg::Execute {
@@ -186,6 +194,7 @@ struct Params {
             fee_swap: None,
         },
         exact_out: true,
+        pre_swap_out_asset_amount: Uint128::new(0),
         expected_messages: vec![SubMsg {
             id: 0,
             msg: WasmMsg::Execute {
@@ -232,6 +241,7 @@ struct Params {
             fee_swap: None,
         },
         exact_out: true,
+        pre_swap_out_asset_amount: Uint128::new(0),
         expected_messages: vec![SubMsg {
             id: 0,
             msg: WasmMsg::Execute {
@@ -284,6 +294,7 @@ struct Params {
             fee_swap: None,
         },
         exact_out: true,
+        pre_swap_out_asset_amount: Uint128::new(0),
         expected_messages: vec![SubMsg {
             id: 0,
             msg: WasmMsg::Execute {
@@ -323,6 +334,7 @@ struct Params {
             msg: to_json_binary(&"contract_call_msg").unwrap(),
         },
         exact_out: false,
+        pre_swap_out_asset_amount: Uint128::new(0),
         expected_messages: vec![SubMsg {
             id: 0,
             msg: WasmMsg::Execute {
@@ -349,6 +361,7 @@ struct Params {
             msg: to_json_binary(&"contract_call_msg").unwrap(),
         },
         exact_out: false,
+        pre_swap_out_asset_amount: Uint128::new(0),
         expected_messages: vec![SubMsg {
             id: 0,
             msg: WasmMsg::Execute {
@@ -376,6 +389,7 @@ struct Params {
             msg: to_json_binary(&"contract_call_msg").unwrap(),
         },
         exact_out: true,
+        pre_swap_out_asset_amount: Uint128::new(0),
         expected_messages: vec![SubMsg {
             id: 0,
             msg: WasmMsg::Execute {
@@ -410,6 +424,7 @@ struct Params {
             fee_swap: None,
         },
         exact_out: false,
+        pre_swap_out_asset_amount: Uint128::new(0),
         expected_messages: vec![SubMsg {
             id: 0,
             msg: WasmMsg::Execute {
@@ -462,6 +477,7 @@ struct Params {
             fee_swap: None,
         },
         exact_out: false,
+        pre_swap_out_asset_amount: Uint128::new(0),
         expected_messages: vec![SubMsg {
             id: 0,
             msg: WasmMsg::Execute {
@@ -492,6 +508,28 @@ struct Params {
         expected_error: None,
     };
     "Ibc Transfer w/ IBC Fees of same denom as min coin")]
+#[test_case(
+    Params {
+        caller: "entry_point".to_string(),
+        min_asset: Asset::Native(Coin::new(700_000, "os")),
+        post_swap_action: Action::Transfer {
+            to_address: "cosmos1xv9tklw7d82sezh9haa573wufgy59vmwe6xxe5".to_string(),
+        },
+        exact_out: false,
+        pre_swap_out_asset_amount: Uint128::new(200_000),
+        expected_messages: vec![SubMsg {
+            id: 0,
+            msg: BankMsg::Send {
+                to_address: "cosmos1xv9tklw7d82sezh9haa573wufgy59vmwe6xxe5".to_string(),
+                amount: vec![Coin::new(800_000, "os")],
+            }
+            .into(),
+            gas_limit: None,
+            reply_on: Never,
+        }],
+        expected_error: None,
+    };
+    "Pre Swap Out Asset Contract Balance Preserved")]
 #[test_case(
     Params {
         caller: "entry_point".to_string(),
@@ -511,6 +549,7 @@ struct Params {
             fee_swap: None,
         },
         exact_out: false,
+        pre_swap_out_asset_amount: Uint128::new(0),
         expected_messages: vec![],
         expected_error: Some(ContractError::NonNativeIbcTransfer),
     };
@@ -523,6 +562,7 @@ struct Params {
             to_address: "swapper".to_string(),
         },
         exact_out: false,
+        pre_swap_out_asset_amount: Uint128::new(0),
         expected_messages: vec![],
         expected_error: Some(ContractError::ReceivedLessAssetFromSwapsThanMinAsset),
     };
@@ -538,6 +578,7 @@ struct Params {
             to_address: "swapper".to_string(),
         },
         exact_out: false,
+        pre_swap_out_asset_amount: Uint128::new(0),
         expected_messages: vec![],
         expected_error: Some(ContractError::ReceivedLessAssetFromSwapsThanMinAsset),
     };
@@ -550,6 +591,7 @@ struct Params {
             to_address: "swapper".to_string(),
         },
         exact_out: false,
+        pre_swap_out_asset_amount: Uint128::new(0),
         expected_messages: vec![],
         expected_error: Some(ContractError::Unauthorized),
     };
@@ -563,6 +605,7 @@ struct Params {
             msg: to_json_binary(&"contract_call_msg").unwrap(),
         },
         exact_out: false,
+        pre_swap_out_asset_amount: Uint128::new(0),
         expected_messages: vec![],
         expected_error: Some(ContractError::ContractCallAddressBlocked),
     };
@@ -609,6 +652,11 @@ fn test_execute_post_swap_action(params: Params) {
         .save(deps.as_mut().storage, &Addr::unchecked("entry_point"), &())
         .unwrap();
 
+    // Store the pre swap out asset amount
+    PRE_SWAP_OUT_ASSET_AMOUNT
+        .save(deps.as_mut().storage, &params.pre_swap_out_asset_amount)
+        .unwrap();
+
     // Call execute_post_swap_action with the given test parameters
     let res = skip_api_entry_point::contract::execute(
         deps.as_mut(),

contracts/entry-point/tests/test_execute_swap_and_action.rs

@@ -21,7 +21,7 @@ use skip::{
 };
 use skip_api_entry_point::{
     error::ContractError,
-    state::{IBC_TRANSFER_CONTRACT_ADDRESS, SWAP_VENUE_MAP},
+    state::{IBC_TRANSFER_CONTRACT_ADDRESS, PRE_SWAP_OUT_ASSET_AMOUNT, SWAP_VENUE_MAP},
 };
 use test_case::test_case;
 
@@ -1753,6 +1753,10 @@ fn test_execute_swap_and_action(params: Params) {
 
             // Assert the messages in the response are correct
             assert_eq!(res.messages, params.expected_messages,);
+
+            // Assert the pre swap out asset amount set is correct
+            let pre_swap_out_asset_amount = PRE_SWAP_OUT_ASSET_AMOUNT.load(&deps.storage).unwrap();
+            assert_eq!(pre_swap_out_asset_amount, Uint128::from(1_000_000u128));
         }
         Err(err) => {
             // Assert the test expected an error