fix: show no price impact eth to weth (#3923)

* fix: show no price impact eth to weth

Fixed the price estimate values to reflect the correct price estimates depending on whether it is a wrapped trade

* fix: show no price impact eth to weth

Fixed to display the correct price estimates depending on whether it is a wrapped trade (eth -> weth should show no price impact)

* Added ETH->wETH testing

Added a Cypress test to check wrapped value swap has no price impact

* make Cypress test cleaner

cypress/e2e/swap.test.ts

@@ -48,6 +48,13 @@ describe('Swap', () => {
     cy.get('#add-recipient-button').should('not.exist')
   })
 
+  it('ETH to wETH is same value (wrapped swaps have no price impact)', () => {
+    cy.get('#swap-currency-output .open-currency-select-button').click()
+    cy.get('.token-item-0xc778417E063141139Fce010982780140Aa0cD5Ab').click({ force: true })
+    cy.get('#swap-currency-input .token-amount-input').type('0.01', { force: true, delay: 100 })
+    cy.get('#swap-currency-output .token-amount-input').should('have.value', '0.01')
+  })
+
   describe('expert mode', () => {
     beforeEach(() => {
       cy.window().then((win) => {

src/pages/Swap/index.tsx

@@ -147,9 +147,11 @@ export default function Swap({ history }: RouteComponentProps) {
     () => [!trade?.swaps, TradeState.LOADING === tradeState, TradeState.SYNCING === tradeState],
     [trade, tradeState]
   )
-
-  const fiatValueInput = useUSDCValue(trade?.inputAmount)
-  const fiatValueOutput = useUSDCValue(trade?.outputAmount)
+  // show price estimates based on wrap trade
+  const inputValue = showWrap ? parsedAmount : trade?.inputAmount
+  const outputValue = showWrap ? parsedAmount : trade?.outputAmount
+  const fiatValueInput = useUSDCValue(inputValue)
+  const fiatValueOutput = useUSDCValue(outputValue)
   const priceImpact = useMemo(
     () => (routeIsSyncing ? undefined : computeFiatValuePriceImpact(fiatValueInput, fiatValueOutput)),
     [fiatValueInput, fiatValueOutput, routeIsSyncing]