update market rate calculation and input parsing for 0 decimal tokens (#601)

* update market rate calculation and input parsing for 0 decimal tokens

* remove style bump and revert tokens

src/components/ExchangePage/index.jsx

@@ -208,15 +208,15 @@ function getExchangeRate(inputValue, inputDecimals, outputValue, outputDecimals,
       if (invert) {
         return inputValue
           .mul(factor)
-          .div(outputValue)
           .mul(ethers.utils.bigNumberify(10).pow(ethers.utils.bigNumberify(outputDecimals)))
           .div(ethers.utils.bigNumberify(10).pow(ethers.utils.bigNumberify(inputDecimals)))
+          .div(outputValue)
       } else {
         return outputValue
           .mul(factor)
-          .div(inputValue)
           .mul(ethers.utils.bigNumberify(10).pow(ethers.utils.bigNumberify(inputDecimals)))
           .div(ethers.utils.bigNumberify(10).pow(ethers.utils.bigNumberify(outputDecimals)))
+          .div(inputValue)
       }
     }
   } catch {}
@@ -560,7 +560,7 @@ export default function ExchangePage({ initialCurrency, sending = false, params
   )
 
   const percentSlippage =
-    exchangeRate && marketRate
+    exchangeRate && marketRate && !marketRate.isZero()
       ? exchangeRate
           .sub(marketRate)
           .abs()

src/pages/Pool/AddLiquidity.js

@@ -178,15 +178,15 @@ function getExchangeRate(inputValue, inputDecimals, outputValue, outputDecimals,
       if (invert) {
         return inputValue
           .mul(factor)
-          .div(outputValue)
           .mul(ethers.utils.bigNumberify(10).pow(ethers.utils.bigNumberify(outputDecimals)))
           .div(ethers.utils.bigNumberify(10).pow(ethers.utils.bigNumberify(inputDecimals)))
+          .div(outputValue)
       } else {
         return outputValue
           .mul(factor)
-          .div(inputValue)
           .mul(ethers.utils.bigNumberify(10).pow(ethers.utils.bigNumberify(inputDecimals)))
           .div(ethers.utils.bigNumberify(10).pow(ethers.utils.bigNumberify(outputDecimals)))
+          .div(inputValue)
       }
     }
   } catch {}
@@ -221,6 +221,7 @@ export default function AddLiquidity({ params }) {
   const [outputValueParsed, setOutputValueParsed] = useState()
   const [inputError, setInputError] = useState()
   const [outputError, setOutputError] = useState()
+  const [zeroDecimalError, setZeroDecimalError] = useState()
 
   const [brokenTokenWarning, setBrokenTokenWarning] = useState()
 
@@ -353,6 +354,8 @@ export default function AddLiquidity({ params }) {
     if (brokenTokenWarning) {
       contextualInfo = t('brokenToken')
       isError = true
+    } else if (zeroDecimalError) {
+      contextualInfo = zeroDecimalError
     } else if (inputError || outputError) {
       contextualInfo = inputError || outputError
       isError = true
@@ -433,14 +436,18 @@ export default function AddLiquidity({ params }) {
 
   useEffect(() => {
     if (isNewExchange) {
+      setZeroDecimalError()
       if (inputValue) {
         const parsedInputValue = ethers.utils.parseUnits(inputValue, 18)
         setInputValueParsed(parsedInputValue)
       }
-
       if (outputValue) {
+        try {
           const parsedOutputValue = ethers.utils.parseUnits(outputValue, decimals)
           setOutputValueParsed(parsedOutputValue)
+        } catch {
+          setZeroDecimalError('Invalid input. For 0 decimal tokens only supply whole number token amounts.')
+        }
       }
     }
   }, [decimals, inputValue, isNewExchange, outputValue])
@@ -568,7 +575,8 @@ export default function AddLiquidity({ params }) {
   }, [outputValueParsed, allowance, t])
 
   const isActive = active && account
-  const isValid = (inputError === null || outputError === null) && !showUnlock && !brokenTokenWarning
+  const isValid =
+    (inputError === null || outputError === null) && !zeroDecimalError && !showUnlock && !brokenTokenWarning
 
   return (
     <>

src/pages/Pool/RemoveLiquidity.js

@@ -110,15 +110,15 @@ function getExchangeRate(inputValue, inputDecimals, outputValue, outputDecimals,
       if (invert) {
         return inputValue
           .mul(factor)
-          .div(outputValue)
           .mul(ethers.utils.bigNumberify(10).pow(ethers.utils.bigNumberify(outputDecimals)))
           .div(ethers.utils.bigNumberify(10).pow(ethers.utils.bigNumberify(inputDecimals)))
+          .div(outputValue)
       } else {
         return outputValue
           .mul(factor)
-          .div(inputValue)
           .mul(ethers.utils.bigNumberify(10).pow(ethers.utils.bigNumberify(inputDecimals)))
           .div(ethers.utils.bigNumberify(10).pow(ethers.utils.bigNumberify(outputDecimals)))
+          .div(inputValue)
       }
     }
   } catch {}
@@ -222,22 +222,25 @@ export default function RemoveLiquidity({ params }) {
     ownershipPercentage &&
     exchangeTokenBalance.mul(ownershipPercentage).div(ethers.utils.bigNumberify(10).pow(ethers.utils.bigNumberify(18)))
 
-  const ETHPer =
-    exchangeETHBalance && totalPoolTokens && !totalPoolTokens.isZero()
-      ? exchangeETHBalance.mul(ethers.utils.bigNumberify(10).pow(ethers.utils.bigNumberify(18))).div(totalPoolTokens)
+  const ETHPer = exchangeETHBalance
+    ? exchangeETHBalance.mul(ethers.utils.bigNumberify(10).pow(ethers.utils.bigNumberify(18)))
     : undefined
-  const tokenPer =
-    exchangeTokenBalance && totalPoolTokens && !totalPoolTokens.isZero()
-      ? exchangeTokenBalance.mul(ethers.utils.bigNumberify(10).pow(ethers.utils.bigNumberify(18))).div(totalPoolTokens)
+  const tokenPer = exchangeTokenBalance
+    ? exchangeTokenBalance.mul(ethers.utils.bigNumberify(10).pow(ethers.utils.bigNumberify(18)))
     : undefined
 
   const ethWithdrawn =
-    ETHPer && valueParsed
-      ? ETHPer.mul(valueParsed).div(ethers.utils.bigNumberify(10).pow(ethers.utils.bigNumberify(18)))
+    ETHPer && valueParsed && totalPoolTokens && !totalPoolTokens.isZero()
+      ? ETHPer.mul(valueParsed)
+          .div(ethers.utils.bigNumberify(10).pow(ethers.utils.bigNumberify(18)))
+          .div(totalPoolTokens)
       : undefined
   const tokenWithdrawn =
-    tokenPer && valueParsed
-      ? tokenPer.mul(valueParsed).div(ethers.utils.bigNumberify(10).pow(ethers.utils.bigNumberify(18)))
+    tokenPer && valueParsed && totalPoolTokens && !totalPoolTokens.isZero()
+      ? tokenPer
+          .mul(valueParsed)
+          .div(ethers.utils.bigNumberify(10).pow(ethers.utils.bigNumberify(18)))
+          .div(totalPoolTokens)
       : undefined
 
   const ethWithdrawnMin = ethWithdrawn ? calculateSlippageBounds(ethWithdrawn).minimum : undefined