Check if swapTokenValue is negative and set prefix accordingly (#9743)

* Check if swapTokenValue is negative and set prefix accordingly

Co-authored-by: Mark Stacey <markjstacey@gmail.com>

Co-authored-by: Mark Stacey <markjstacey@gmail.com>

ui/app/hooks/useSwappedTokenValue.js

@@ -44,6 +44,11 @@ export function useSwappedTokenValue (transactionGroup, currentAsset) {
       decimals,
     )
     : transactionCategory === SWAP && primaryTransaction.swapTokenValue
+
+  const isNegative = typeof swapTokenValue === 'string'
+    ? Math.sign(swapTokenValue) === -1
+    : false
+
   const _swapTokenFiatAmount = useTokenFiatAmount(
     address,
     swapTokenValue || '',
@@ -52,5 +57,5 @@ export function useSwappedTokenValue (transactionGroup, currentAsset) {
   const swapTokenFiatAmount = (
     swapTokenValue && isViewingReceivedTokenFromSwap && _swapTokenFiatAmount
   )
-  return { swapTokenValue, swapTokenFiatAmount, isViewingReceivedTokenFromSwap }
+  return { swapTokenValue, swapTokenFiatAmount, isViewingReceivedTokenFromSwap, isNegative }
 }

ui/app/hooks/useTransactionDisplayData.js

@@ -115,7 +115,7 @@ export function useTransactionDisplayData (transactionGroup) {
   // The primary title of the Tx that will be displayed in the activity list
   let title
 
-  const { swapTokenValue, swapTokenFiatAmount, isViewingReceivedTokenFromSwap } = useSwappedTokenValue(transactionGroup, currentAsset)
+  const { swapTokenValue, isNegative, swapTokenFiatAmount, isViewingReceivedTokenFromSwap } = useSwappedTokenValue(transactionGroup, currentAsset)
 
   // There are seven types of transaction entries that are currently differentiated in the design
   // 1. Signature request
@@ -145,8 +145,13 @@ export function useTransactionDisplayData (transactionGroup) {
       : initialTransaction.sourceTokenSymbol
     primaryDisplayValue = swapTokenValue
     secondaryDisplayValue = swapTokenFiatAmount
-    prefix = isViewingReceivedTokenFromSwap ? '+' : '-'
-
+    if (isNegative) {
+      prefix = ''
+    } else if (isViewingReceivedTokenFromSwap) {
+      prefix = '+'
+    } else {
+      prefix = '-'
+    }
   } else if (transactionCategory === SWAP_APPROVAL) {
     category = TRANSACTION_CATEGORY_APPROVAL
     title = t('swapApproval', [primaryTransaction.sourceTokenSymbol])