feat(utxo): add new fixed txfee option for DINGO-like coins (#2454)

This commit make txsize not round up by default. It then adds a new fixed tx fee option "dingo_fee"=true, with rounding up, that could be set for a coin in the coins file.

Author: dimxy

mm2src/coins/eth.rs

@@ -5987,7 +5987,6 @@ impl MmCoin for EthCoin {
         &self,
         value: TradePreimageValue,
         stage: FeeApproxStage,
-        include_refund_fee: bool,
     ) -> TradePreimageResult<TradeFee> {
         let pay_for_gas_option = self
             .get_swap_pay_for_gas_option(self.get_swap_transaction_fee_policy())
@@ -5997,7 +5996,7 @@ impl MmCoin for EthCoin {
         let gas_limit = match self.coin_type {
             EthCoinType::Eth => {
                 // this gas_limit includes gas for `ethPayment` and optionally `senderRefund` contract calls
-                if include_refund_fee {
+                if matches!(stage, FeeApproxStage::OrderIssueMax | FeeApproxStage::TradePreimageMax) {
                     U256::from(self.gas_limit.eth_payment) + U256::from(self.gas_limit.eth_sender_refund)
                 } else {
                     U256::from(self.gas_limit.eth_payment)
@@ -6027,7 +6026,7 @@ impl MmCoin for EthCoin {
                     gas += approve_gas_limit;
                 }
                 // add 'senderRefund' gas if requested
-                if include_refund_fee {
+                if matches!(stage, FeeApproxStage::TradePreimage | FeeApproxStage::TradePreimageMax) {
                     gas += U256::from(self.gas_limit.erc20_sender_refund);
                 }
                 gas
@@ -6808,10 +6807,10 @@ fn increase_gas_price_by_stage(pay_for_gas_option: PayForGasOption, level: &FeeA
             FeeApproxStage::StartSwap => {
                 increase_by_percent_one_gwei(gas_price, GAS_PRICE_APPROXIMATION_PERCENT_ON_START_SWAP)
             },
-            FeeApproxStage::OrderIssue => {
+            FeeApproxStage::OrderIssue | FeeApproxStage::OrderIssueMax => {
                 increase_by_percent_one_gwei(gas_price, GAS_PRICE_APPROXIMATION_PERCENT_ON_ORDER_ISSUE)
             },
-            FeeApproxStage::TradePreimage => {
+            FeeApproxStage::TradePreimage | FeeApproxStage::TradePreimageMax => {
                 increase_by_percent_one_gwei(gas_price, GAS_PRICE_APPROXIMATION_PERCENT_ON_TRADE_PREIMAGE)
             },
             FeeApproxStage::WatcherPreimage => {

mm2src/coins/eth/eth_tests.rs

@@ -331,34 +331,26 @@ fn get_sender_trade_preimage() {
     let actual = block_on(coin.get_sender_trade_fee(
         TradePreimageValue::UpperBound(150.into()),
         FeeApproxStage::WithoutApprox,
-        true,
     ))
     .expect("!get_sender_trade_fee");
-    let expected = expected_fee(GAS_PRICE, gas_limit::ETH_PAYMENT + gas_limit::ETH_SENDER_REFUND);
+    let expected = expected_fee(GAS_PRICE, gas_limit::ETH_PAYMENT);
     assert_eq!(actual, expected);
 
     let value = u256_to_big_decimal(100.into(), 18).expect("!u256_to_big_decimal");
-    let actual =
-        block_on(coin.get_sender_trade_fee(TradePreimageValue::Exact(value), FeeApproxStage::OrderIssue, true))
-            .expect("!get_sender_trade_fee");
-    let expected = expected_fee(
-        GAS_PRICE_APPROXIMATION_ON_ORDER_ISSUE,
-        gas_limit::ETH_PAYMENT + gas_limit::ETH_SENDER_REFUND,
-    );
+    let actual = block_on(coin.get_sender_trade_fee(TradePreimageValue::Exact(value), FeeApproxStage::OrderIssue))
+        .expect("!get_sender_trade_fee");
+    let expected = expected_fee(GAS_PRICE_APPROXIMATION_ON_ORDER_ISSUE, gas_limit::ETH_PAYMENT);
     assert_eq!(actual, expected);
 
     let value = u256_to_big_decimal(1.into(), 18).expect("!u256_to_big_decimal");
-    let actual = block_on(coin.get_sender_trade_fee(TradePreimageValue::Exact(value), FeeApproxStage::StartSwap, true))
+    let actual = block_on(coin.get_sender_trade_fee(TradePreimageValue::Exact(value), FeeApproxStage::StartSwap))
         .expect("!get_sender_trade_fee");
-    let expected = expected_fee(
-        GAS_PRICE_APPROXIMATION_ON_START_SWAP,
-        gas_limit::ETH_PAYMENT + gas_limit::ETH_SENDER_REFUND,
-    );
+    let expected = expected_fee(GAS_PRICE_APPROXIMATION_ON_START_SWAP, gas_limit::ETH_PAYMENT);
     assert_eq!(actual, expected);
 
     let value = u256_to_big_decimal(10000000000u64.into(), 18).expect("!u256_to_big_decimal");
     let actual =
-        block_on(coin.get_sender_trade_fee(TradePreimageValue::Exact(value), FeeApproxStage::TradePreimage, true))
+        block_on(coin.get_sender_trade_fee(TradePreimageValue::Exact(value), FeeApproxStage::TradePreimageMax))
             .expect("!get_sender_trade_fee");
     let expected = expected_fee(
         GAS_PRICE_APPROXIMATION_ON_TRADE_PREIMAGE,
@@ -405,58 +397,46 @@ fn get_erc20_sender_trade_preimage() {
     // value is allowed
     unsafe { ALLOWANCE = 1000 };
     let value = u256_to_big_decimal(1000.into(), 18).expect("u256_to_big_decimal");
-    let actual = block_on(coin.get_sender_trade_fee(
-        TradePreimageValue::UpperBound(value),
-        FeeApproxStage::WithoutApprox,
-        true,
-    ))
-    .expect("!get_sender_trade_fee");
+    let actual =
+        block_on(coin.get_sender_trade_fee(TradePreimageValue::UpperBound(value), FeeApproxStage::WithoutApprox))
+            .expect("!get_sender_trade_fee");
     log!("{:?}", actual.amount.to_decimal());
     unsafe { assert!(!ESTIMATE_GAS_CALLED) }
-    assert_eq!(
-        actual,
-        expected_trade_fee(gas_limit::ERC20_PAYMENT + gas_limit::ERC20_SENDER_REFUND, GAS_PRICE)
-    );
+    assert_eq!(actual, expected_trade_fee(gas_limit::ERC20_PAYMENT, GAS_PRICE));
 
     // value is greater than allowance
     unsafe { ALLOWANCE = 999 };
     let value = u256_to_big_decimal(1000.into(), 18).expect("u256_to_big_decimal");
-    let actual =
-        block_on(coin.get_sender_trade_fee(TradePreimageValue::UpperBound(value), FeeApproxStage::StartSwap, true))
-            .expect("!get_sender_trade_fee");
+    let actual = block_on(coin.get_sender_trade_fee(TradePreimageValue::UpperBound(value), FeeApproxStage::StartSwap))
+        .expect("!get_sender_trade_fee");
     unsafe {
         assert!(ESTIMATE_GAS_CALLED);
         ESTIMATE_GAS_CALLED = false;
     }
     assert_eq!(
         actual,
         expected_trade_fee(
-            gas_limit::ERC20_PAYMENT + gas_limit::ERC20_SENDER_REFUND + APPROVE_GAS_LIMIT,
+            gas_limit::ERC20_PAYMENT + APPROVE_GAS_LIMIT,
             GAS_PRICE_APPROXIMATION_ON_START_SWAP
         )
     );
 
     // value is allowed
     unsafe { ALLOWANCE = 1000 };
     let value = u256_to_big_decimal(999.into(), 18).expect("u256_to_big_decimal");
-    let actual =
-        block_on(coin.get_sender_trade_fee(TradePreimageValue::Exact(value), FeeApproxStage::OrderIssue, true))
-            .expect("!get_sender_trade_fee");
+    let actual = block_on(coin.get_sender_trade_fee(TradePreimageValue::Exact(value), FeeApproxStage::OrderIssue))
+        .expect("!get_sender_trade_fee");
     unsafe { assert!(!ESTIMATE_GAS_CALLED) }
     assert_eq!(
         actual,
-        expected_trade_fee(
-            gas_limit::ERC20_PAYMENT + gas_limit::ERC20_SENDER_REFUND,
-            GAS_PRICE_APPROXIMATION_ON_ORDER_ISSUE
-        )
+        expected_trade_fee(gas_limit::ERC20_PAYMENT, GAS_PRICE_APPROXIMATION_ON_ORDER_ISSUE)
     );
 
     // value is greater than allowance
     unsafe { ALLOWANCE = 1000 };
     let value = u256_to_big_decimal(1500.into(), 18).expect("u256_to_big_decimal");
-    let actual =
-        block_on(coin.get_sender_trade_fee(TradePreimageValue::Exact(value), FeeApproxStage::TradePreimage, true))
-            .expect("!get_sender_trade_fee");
+    let actual = block_on(coin.get_sender_trade_fee(TradePreimageValue::Exact(value), FeeApproxStage::TradePreimage))
+        .expect("!get_sender_trade_fee");
     unsafe {
         assert!(ESTIMATE_GAS_CALLED);
         ESTIMATE_GAS_CALLED = false;

mm2src/coins/lightning.rs

@@ -1303,7 +1303,6 @@ impl MmCoin for LightningCoin {
         &self,
         _value: TradePreimageValue,
         _stage: FeeApproxStage,
-        _include_refund_fee: bool,
     ) -> TradePreimageResult<TradeFee> {
         Ok(TradeFee {
             coin: self.ticker().to_owned(),

mm2src/coins/lp_coins.rs

@@ -2627,6 +2627,7 @@ impl TransactionDetails {
     }
 }
 
+/// Transaction fee to pay for swap transactions (could be total for two transactions: taker fee and payment fee txns)
 #[derive(Clone, Debug, PartialEq, Serialize)]
 pub struct TradeFee {
     pub coin: String,
@@ -2712,6 +2713,8 @@ impl AddAssign for CoinBalance {
 }
 
 /// The approximation is needed to cover the dynamic miner fee changing during a swap.
+/// Also used to indicate refund fee is needed for eth
+/// Also used to indicate utxo fee correction is needed due to a possible change output
 #[derive(Clone, Copy, Debug)]
 pub enum FeeApproxStage {
     /// Do not increase the trade fee.
@@ -2722,8 +2725,12 @@ pub enum FeeApproxStage {
     WatcherPreimage,
     /// Increase the trade fee significantly.
     OrderIssue,
-    /// Increase the trade fee largely.
+    /// Increase the trade fee significantly (used to calculate max volume).
+    OrderIssueMax,
+    /// Increase the trade fee largely in the trade_preimage rpc.
     TradePreimage,
+    /// Increase the trade fee in the trade_preimage rpc (used to calculate max volume for trade preimage).
+    TradePreimageMax,
 }
 
 #[derive(Debug)]
@@ -3622,7 +3629,6 @@ pub trait MmCoin: SwapOps + WatcherOps + MarketCoinOps + Send + Sync + 'static {
         &self,
         value: TradePreimageValue,
         stage: FeeApproxStage,
-        include_refund_fee: bool,
     ) -> TradePreimageResult<TradeFee>;
 
     /// Get fee to be paid by receiver per whole swap and check if the wallet has sufficient balance to pay the fee.

mm2src/coins/qrc20.rs

@@ -539,7 +539,9 @@ impl Qrc20Coin {
     /// or should be sum of gas fee of all contract calls.
     pub async fn get_qrc20_tx_fee(&self, gas_fee: u64) -> Result<u64, String> {
         match try_s!(self.get_fee_rate().await) {
-            ActualFeeRate::Dynamic(amount) | ActualFeeRate::FixedPerKb(amount) => Ok(amount + gas_fee),
+            ActualFeeRate::Dynamic(amount)
+            | ActualFeeRate::FixedPerKb(amount)
+            | ActualFeeRate::FixedPerKbDingo(amount) => Ok(amount + gas_fee),
         }
     }
 
@@ -1289,7 +1291,6 @@ impl MmCoin for Qrc20Coin {
         &self,
         value: TradePreimageValue,
         stage: FeeApproxStage,
-        include_refund_fee: bool,
     ) -> TradePreimageResult<TradeFee> {
         let decimals = self.utxo.decimals;
         // pass the dummy params
@@ -1323,7 +1324,7 @@ impl MmCoin for Qrc20Coin {
         };
 
         // Optionally calculate refund fee.
-        let sender_refund_fee = if include_refund_fee {
+        let sender_refund_fee = if matches!(stage, FeeApproxStage::TradePreimage | FeeApproxStage::TradePreimageMax) {
             let sender_refund_output = self
                 .sender_refund_output(&self.swap_contract_address, swap_id, value, secret_hash, receiver_addr)
                 .map_mm_err()?;

mm2src/coins/qrc20/qrc20_tests.rs

@@ -19,7 +19,7 @@ cfg_native!(
     use mocktopus::mocking::{MockResult, Mockable};
 );
 
-const EXPECTED_TX_FEE: i64 = 1000;
+const DEFAULT_TX_FEE_RATE: i64 = 1000;
 const CONTRACT_CALL_GAS_FEE: i64 = (QRC20_GAS_LIMIT_DEFAULT * QRC20_GAS_PRICE_DEFAULT) as i64;
 const SWAP_PAYMENT_GAS_FEE: i64 = (QRC20_PAYMENT_GAS_LIMIT * QRC20_GAS_PRICE_DEFAULT) as i64;
 const TAKER_PAYMENT_SPEND_SEARCH_INTERVAL: f64 = 1.;
@@ -59,9 +59,9 @@ pub fn qrc20_coin_for_test(priv_key: [u8; 32], fallback_swap: Option<&str>) -> (
     (ctx, coin)
 }
 
-fn check_tx_fee(coin: &Qrc20Coin, expected_tx_fee: ActualFeeRate) {
-    let actual_tx_fee = block_on(coin.get_fee_rate()).unwrap();
-    assert_eq!(actual_tx_fee, expected_tx_fee);
+fn check_fee_rate(coin: &Qrc20Coin, expected_fee_rate: ActualFeeRate) {
+    let actual_fee_rate = block_on(coin.get_fee_rate()).unwrap();
+    assert_eq!(actual_fee_rate, expected_fee_rate);
 }
 
 #[cfg(not(target_arch = "wasm32"))]
@@ -144,7 +144,7 @@ fn test_withdraw_impl_fee_details() {
         // 1000 from satoshi,
         // where decimals = 8,
         //       1000 is fixed fee
-        "miner_fee": "0.00001",
+        "miner_fee": "0.00000299",
         "gas_limit": 2_500_000,
         "gas_price": 40,
         // (gas_limit * gas_price) from satoshi in Qtum
@@ -715,12 +715,12 @@ fn test_get_trade_fee() {
         172, 110, 180, 13, 123, 179, 10, 49,
     ];
     let (_ctx, coin) = qrc20_coin_for_test(priv_key, None);
-    // check if the coin's tx fee is expected
-    check_tx_fee(&coin, ActualFeeRate::FixedPerKb(EXPECTED_TX_FEE as u64));
+    // check if the coin's tx fee rate is expected
+    check_fee_rate(&coin, ActualFeeRate::FixedPerKb(DEFAULT_TX_FEE_RATE as u64));
 
     let actual_trade_fee = block_on_f01(coin.get_trade_fee()).unwrap();
     let expected_trade_fee_amount = big_decimal_from_sat(
-        2 * CONTRACT_CALL_GAS_FEE + SWAP_PAYMENT_GAS_FEE + EXPECTED_TX_FEE,
+        2 * CONTRACT_CALL_GAS_FEE + SWAP_PAYMENT_GAS_FEE + DEFAULT_TX_FEE_RATE,
         coin.utxo.decimals,
     );
     let expected = TradeFee {
@@ -742,20 +742,22 @@ fn test_sender_trade_preimage_zero_allowance() {
         231, 153, 202, 20, 238, 120, 64,
     ];
     let (_ctx, coin) = qrc20_coin_for_test(priv_key, None);
-    // check if the coin's tx fee is expected
-    check_tx_fee(&coin, ActualFeeRate::FixedPerKb(EXPECTED_TX_FEE as u64));
+    const EXPECTED_PAYMENT_TX_FEE: i64 = 535;
+    const EXPECTED_REFUND_TX_FEE: i64 = 396;
+    // check if the coin's tx fee rate is expected
+    check_fee_rate(&coin, ActualFeeRate::FixedPerKb(DEFAULT_TX_FEE_RATE as u64));
 
     let allowance = block_on(coin.allowance(coin.swap_contract_address)).expect("!allowance");
     assert_eq!(allowance, 0.into());
 
     let erc20_payment_fee_with_one_approve = big_decimal_from_sat(
-        CONTRACT_CALL_GAS_FEE + SWAP_PAYMENT_GAS_FEE + EXPECTED_TX_FEE,
+        CONTRACT_CALL_GAS_FEE + SWAP_PAYMENT_GAS_FEE + EXPECTED_PAYMENT_TX_FEE,
         coin.utxo.decimals,
     );
-    let sender_refund_fee = big_decimal_from_sat(CONTRACT_CALL_GAS_FEE + EXPECTED_TX_FEE, coin.utxo.decimals);
+    let sender_refund_fee = big_decimal_from_sat(CONTRACT_CALL_GAS_FEE + EXPECTED_REFUND_TX_FEE, coin.utxo.decimals);
 
     let actual =
-        block_on(coin.get_sender_trade_fee(TradePreimageValue::Exact(1.into()), FeeApproxStage::WithoutApprox, true))
+        block_on(coin.get_sender_trade_fee(TradePreimageValue::Exact(1.into()), FeeApproxStage::TradePreimageMax)) // pass TradePreimageMax to add change output txfee, to correct the max vol calc
             .expect("!get_sender_trade_fee");
     // one `approve` contract call should be included into the expected trade fee
     let expected = TradeFee {
@@ -778,24 +780,28 @@ fn test_sender_trade_preimage_with_allowance() {
         143, 221, 19, 47, 74, 175, 100,
     ];
     let (_ctx, coin) = qrc20_coin_for_test(priv_key, None);
-    // check if the coin's tx fee is expected
-    check_tx_fee(&coin, ActualFeeRate::FixedPerKb(EXPECTED_TX_FEE as u64));
+    const EXPECTED_PAYMENT_WITHOUT_APPROVE_TX_FEE: i64 = 576;
+    const EXPECTED_PAYMENT_WITH_APPROVES_TX_FEE: i64 = 790;
+    const EXPECTED_REFUND_TX_FEE: i64 = 544;
+    // check if the coin's tx fee rate is expected
+    check_fee_rate(&coin, ActualFeeRate::FixedPerKb(DEFAULT_TX_FEE_RATE as u64));
 
     let allowance = block_on(coin.allowance(coin.swap_contract_address)).expect("!allowance");
     assert_eq!(allowance, 300_000_000.into());
 
-    let erc20_payment_fee_without_approve =
-        big_decimal_from_sat(SWAP_PAYMENT_GAS_FEE + EXPECTED_TX_FEE, coin.utxo.decimals);
+    let erc20_payment_fee_without_approve = big_decimal_from_sat(
+        SWAP_PAYMENT_GAS_FEE + EXPECTED_PAYMENT_WITHOUT_APPROVE_TX_FEE,
+        coin.utxo.decimals,
+    );
     let erc20_payment_fee_with_two_approves = big_decimal_from_sat(
-        2 * CONTRACT_CALL_GAS_FEE + SWAP_PAYMENT_GAS_FEE + EXPECTED_TX_FEE,
+        2 * CONTRACT_CALL_GAS_FEE + SWAP_PAYMENT_GAS_FEE + EXPECTED_PAYMENT_WITH_APPROVES_TX_FEE,
         coin.utxo.decimals,
     );
-    let sender_refund_fee = big_decimal_from_sat(CONTRACT_CALL_GAS_FEE + EXPECTED_TX_FEE, coin.utxo.decimals);
+    let sender_refund_fee = big_decimal_from_sat(CONTRACT_CALL_GAS_FEE + EXPECTED_REFUND_TX_FEE, coin.utxo.decimals);
 
     let actual = block_on(coin.get_sender_trade_fee(
         TradePreimageValue::Exact(BigDecimal::try_from(2.5).unwrap()),
-        FeeApproxStage::WithoutApprox,
-        true,
+        FeeApproxStage::TradePreimageMax,
     ))
     .expect("!get_sender_trade_fee");
     // the expected fee should not include any `approve` contract call
@@ -808,8 +814,7 @@ fn test_sender_trade_preimage_with_allowance() {
 
     let actual = block_on(coin.get_sender_trade_fee(
         TradePreimageValue::Exact(BigDecimal::try_from(3.5).unwrap()),
-        FeeApproxStage::WithoutApprox,
-        true,
+        FeeApproxStage::TradePreimageMax,
     ))
     .expect("!get_sender_trade_fee");
     // two `approve` contract calls should be included into the expected trade fee
@@ -865,11 +870,10 @@ fn test_get_sender_trade_fee_preimage_for_correct_ticker() {
     ))
     .unwrap();
 
-    let actual =
-        block_on(coin.get_sender_trade_fee(TradePreimageValue::Exact(0.into()), FeeApproxStage::OrderIssue, true))
-            .err()
-            .unwrap()
-            .into_inner();
+    let actual = block_on(coin.get_sender_trade_fee(TradePreimageValue::Exact(0.into()), FeeApproxStage::OrderIssue))
+        .err()
+        .unwrap()
+        .into_inner();
     // expecting TradePreimageError::NotSufficientBalance
     let expected = TradePreimageError::NotSufficientBalance {
         coin: "tQTUM".to_string(),
@@ -889,8 +893,9 @@ fn test_receiver_trade_preimage() {
         143, 221, 19, 47, 74, 175, 100,
     ];
     let (_ctx, coin) = qrc20_coin_for_test(priv_key, None);
-    // check if the coin's tx fee is expected
-    check_tx_fee(&coin, ActualFeeRate::FixedPerKb(EXPECTED_TX_FEE as u64));
+    const EXPECTED_TX_FEE: i64 = 544;
+    // check if the coin's tx fee rate is expected
+    check_fee_rate(&coin, ActualFeeRate::FixedPerKb(DEFAULT_TX_FEE_RATE as u64));
 
     let actual =
         block_on_f01(coin.get_receiver_trade_fee(FeeApproxStage::WithoutApprox)).expect("!get_receiver_trade_fee");
@@ -914,8 +919,9 @@ fn test_taker_fee_tx_fee() {
         143, 221, 19, 47, 74, 175, 100,
     ];
     let (_ctx, coin) = qrc20_coin_for_test(priv_key, None);
-    // check if the coin's tx fee is expected
-    check_tx_fee(&coin, ActualFeeRate::FixedPerKb(EXPECTED_TX_FEE as u64));
+    const EXPECTED_TX_FEE: i64 = 447;
+    // check if the coin's tx fee rate is expected
+    check_fee_rate(&coin, ActualFeeRate::FixedPerKb(DEFAULT_TX_FEE_RATE as u64));
     let expected_balance = CoinBalance {
         spendable: BigDecimal::from(5u32),
         unspendable: BigDecimal::from(0u32),

mm2src/coins/siacoin.rs

@@ -284,7 +284,6 @@ impl MmCoin for SiaCoin {
         &self,
         _value: TradePreimageValue,
         _stage: FeeApproxStage,
-        _include_refund_fee: bool,
     ) -> TradePreimageResult<TradeFee> {
         unimplemented!()
     }