Detect and warn user for amount changes within transaction acceleration

Author: samholmes

CHANGELOG.md

@@ -2,6 +2,8 @@
 
 ## Unreleased
 
+- added: New 'Lower Send Amount' warning for transaction acceleration
+
 ## 3.21.0
 
 - added: Paybis buy/sell in Brazil, Columbia, and Mexico

src/components/modals/AccelerateTxModal.tsx

@@ -1,3 +1,4 @@
+import { abs, lt, sub } from 'biggystring'
 import { EdgeCurrencyWallet, EdgeDenomination, EdgeTransaction } from 'edge-core-js'
 import React, { PureComponent } from 'react'
 import { Text, View } from 'react-native'
@@ -8,6 +9,7 @@ import { getDisplayDenominationFromState, getExchangeDenominationFromState } fro
 import { connect } from '../../types/reactRedux'
 import { GuiExchangeRates } from '../../types/types'
 import { convertTransactionFeeToDisplayFee } from '../../util/utils'
+import { WarningCard } from '../cards/WarningCard'
 import { cacheStyles, Theme, ThemeProps, withTheme } from '../services/ThemeContext'
 import { ModalMessage, ModalTitle } from '../themed/ModalParts'
 import { Slider } from '../themed/Slider'
@@ -105,6 +107,7 @@ export class AccelerateTxModalComponent extends PureComponent<Props, State> {
     const oldFee = this.getTxFeeDisplay(replacedTx)
     const newFee = this.getTxFeeDisplay(acceleratedTx)
 
+    const isLowerAmount = lt(getTxSendAmount(acceleratedTx), getTxSendAmount(replacedTx))
     const isSending = status === 'sending'
 
     return (
@@ -115,6 +118,13 @@ export class AccelerateTxModalComponent extends PureComponent<Props, State> {
           <Tile type="static" title={lstrings.transaction_details_accelerate_transaction_old_fee_title} body={oldFee} />
           {newFee == null ? null : <Tile type="static" title={lstrings.transaction_details_accelerate_transaction_new_fee_title} body={newFee} />}
         </View>
+        {isLowerAmount ? (
+          <WarningCard
+            title={lstrings.transaction_details_accelerate_transaction_lower_amount_tx_title}
+            points={[lstrings.transaction_details_accelerate_transaction_lower_amount_tx_message]}
+            marginRem={[1.5, 1]}
+          />
+        ) : null}
         {error == null ? null : (
           <View style={styles.error}>
             <Text style={styles.errorText} numberOfLines={3}>
@@ -169,3 +179,11 @@ export const AccelerateTxModal = connect<StateProps, DispatchProps, OwnProps>(
     }
   })
 )(withTheme(AccelerateTxModalComponent))
+
+function getTxSendAmount(edgeTransaction: EdgeTransaction): string {
+  // Transaction amounts are negative for send transactions
+  const nativeAmount = abs(edgeTransaction.nativeAmount)
+  // Parent network fee is used for token sends
+  const feeAmount = edgeTransaction.parentNetworkFee ?? edgeTransaction.networkFee
+  return sub(nativeAmount, feeAmount)
+}

src/locales/en_US.ts

@@ -664,6 +664,8 @@ const strings = {
   transaction_details_accelerate_transaction_slider_disabled: 'Unable to Accelerate Transaction',
   transaction_details_accelerate_transaction_fee_too_low: 'Accelerated transaction fee is too low. Fee has been updated. Please try again.',
   transaction_details_accelerate_transaction_sent: 'Your transaction has been accelerated.',
+  transaction_details_accelerate_transaction_lower_amount_tx_title: 'Lower Send Amount',
+  transaction_details_accelerate_transaction_lower_amount_tx_message: `In order to accelerate this transaction, the recipient's amount will be lower due to insufficient balance to cover the new fee.`,
   transaction_details_exchange_details: 'Exchange Details',
   transaction_details_exchange_service: 'Exchange Service',
   transaction_details_exchange_order_id: 'Order ID',

src/locales/strings/enUS.json

@@ -595,6 +595,8 @@
   "transaction_details_accelerate_transaction_slider_disabled": "Unable to Accelerate Transaction",
   "transaction_details_accelerate_transaction_fee_too_low": "Accelerated transaction fee is too low. Fee has been updated. Please try again.",
   "transaction_details_accelerate_transaction_sent": "Your transaction has been accelerated.",
+  "transaction_details_accelerate_transaction_lower_amount_tx_title": "Lower Send Amount",
+  "transaction_details_accelerate_transaction_lower_amount_tx_message": "In order to accelerate this transaction, the recipient's amount will be lower due to insufficient balance to cover the new fee.",
   "transaction_details_exchange_details": "Exchange Details",
   "transaction_details_exchange_service": "Exchange Service",
   "transaction_details_exchange_order_id": "Order ID",