mainnet (#782)

* mainnet config

* fix token + pair sorting

* standardize wrapped useWeb3React imports

* add final return to pair sorting

* add connecting pairs

* break tokens out into separate files

revert isAddress change

* filter out duplicate pairs

* remove add liquidity prompts

* link to v1 trades that are invalid on v2

* forward v2 subdomain to apex

* update blog link

* get rid of smart quotes

* link to uniswap info in position card

* improve pair sorting/searching

break out token identification

fix crash on early pool position clicks

change pair token separator from : to /

netlify.toml

@@ -7,6 +7,12 @@
   conditions = {Country=["BY","CU","IR","IQ","CI","LR","KP","SD","SY","ZW"]}
   headers = {Link="<https://uniswap.exchange>"}
 
+# forward v2 subdomain to apex
+[[redirects]]
+  from = "https://v2.uniswap.exchange/*"
+  to = "https://uniswap.exchange/:splat"
+  status = 301
+
 # support SPA setup
 [[redirects]]
   from = "/*"

src/components/Header/index.tsx

@@ -158,15 +158,15 @@ export default function Header() {
   return (
     <HeaderFrame>
       <MigrateBanner>
-        {/* <b>Uniswap V2 is live.&nbsp;</b> Move your liquidity now using the&nbsp; */}
-        <b>Testnet only.</b>&nbsp;Uniswap V2 has not been launched and is coming soon.&nbsp;Read the&nbsp;
-        {/* <Link href="https://migrate.uniswap.exchange/">
-          <b>migration helper</b>
-        </Link>
-        &nbsp;or read the&nbsp; */}
-        <Link href="https://uniswap.org/blog/uniswap-v2/">
+        Uniswap V2 is live! Read the&nbsp;
+        <Link href="https://uniswap.org/blog/launch-uniswap-v2/">
           <b>blog post ↗</b>
         </Link>
+        &nbsp;or&nbsp;
+        <Link href="https://migrate.uniswap.exchange/">
+          <b>migrate your liquidity ↗</b>
+        </Link>
+        .
       </MigrateBanner>
       <RowBetween padding="1rem">
         <HeaderElement>

src/components/PoolFinder/index.tsx

@@ -15,7 +15,7 @@ import { AutoColumn, ColumnCenter } from '../Column'
 import { ButtonPrimary, ButtonDropwdown, ButtonDropwdownLight } from '../Button'
 
 import { useToken } from '../../hooks/Tokens'
-import { useWeb3React } from '@web3-react/core'
+import { useWeb3React } from '../../hooks'
 import { usePairAdder } from '../../state/user/hooks'
 import { usePair } from '../../data/Reserves'
 

src/components/PositionCard/index.tsx

@@ -4,7 +4,7 @@ import { darken } from 'polished'
 import { RouteComponentProps, withRouter } from 'react-router-dom'
 import { Percent, Pair, JSBI } from '@uniswap/sdk'
 
-import { useWeb3React } from '@web3-react/core'
+import { useWeb3React } from '../../hooks'
 import { useTotalSupply } from '../../data/TotalSupply'
 import { useTokenBalance } from '../../state/wallet/hooks'
 
@@ -80,7 +80,7 @@ function PositionCard({ pair, history, border, minimal = false }: PositionCardPr
                 <RowFixed>
                   <DoubleLogo a0={token0?.address || ''} a1={token1?.address || ''} margin={true} size={20} />
                   <Text fontWeight={500} fontSize={20}>
-                    {token0?.symbol}:{token1?.symbol}
+                    {token0?.symbol}/{token1?.symbol}
                   </Text>
                 </RowFixed>
                 <RowFixed>
@@ -134,7 +134,7 @@ function PositionCard({ pair, history, border, minimal = false }: PositionCardPr
             <RowFixed>
               <DoubleLogo a0={token0?.address || ''} a1={token1?.address || ''} margin={true} size={20} />
               <Text fontWeight={500} fontSize={20}>
-                {token0?.symbol}:{token1?.symbol}
+                {token0?.symbol}/{token1?.symbol}
               </Text>
             </RowFixed>
             <RowFixed>
@@ -204,7 +204,7 @@ function PositionCard({ pair, history, border, minimal = false }: PositionCardPr
               )}
 
               <AutoRow justify="center" marginTop={'10px'}>
-                <Link>View pool information ↗</Link>
+                <Link href={`https://uniswap.info/pair/${pair?.liquidityToken.address}`}>View pool information ↗</Link>
               </AutoRow>
               <RowBetween marginTop="10px">
                 <ButtonSecondary

src/components/SearchModal/index.tsx

@@ -182,7 +182,7 @@ function SearchModal({
   const allBalances = useAllTokenBalancesTreatingWETHasETH()
 
   const [searchQuery, setSearchQuery] = useState('')
-  const [sortDirection, setSortDirection] = useState(true)
+  const [invertSearchOrder, setInvertSearchOrder] = useState(false)
 
   const userAddedTokens = useUserAddedTokens()
   const fetchTokenByAddress = useFetchTokenByAddress()
@@ -200,7 +200,7 @@ function SearchModal({
   const [showTokenImport, setShowTokenImport] = useState(false)
 
   // used to help scanning on results, put token found from input on left
-  const [identifiedToken, setIdentifiedToken] = useState<Token | null>()
+  const [identifiedToken, setIdentifiedToken] = useState<Token>()
 
   useEffect(() => {
     const address = isAddress(searchQuery)
@@ -228,37 +228,37 @@ function SearchModal({
   const tokenList = useMemo(() => {
     return Object.keys(allTokens)
       .sort((tokenAddressA, tokenAddressB): number => {
-        if (tokenAddressA && allTokens[tokenAddressA]?.equals(WETH[chainId])) return -1
-        if (tokenAddressB && allTokens[tokenAddressB]?.equals(WETH[chainId])) return 1
-
-        if (allTokens[tokenAddressA].symbol && allTokens[tokenAddressB].symbol) {
-          const aSymbol = allTokens[tokenAddressA].symbol.toLowerCase()
-          const bSymbol = allTokens[tokenAddressB].symbol.toLowerCase()
-          // sort by balance
-          const balanceA = allBalances?.[account]?.[tokenAddressA]
-          const balanceB = allBalances?.[account]?.[tokenAddressB]
-
-          if (balanceA?.greaterThan('0') && !balanceB?.greaterThan('0')) {
-            return sortDirection ? -1 : 1
-          }
-          if (!balanceA?.greaterThan('0') && balanceB?.greaterThan('0')) {
-            return sortDirection ? 1 : -1
-          }
-          return aSymbol < bSymbol ? -1 : aSymbol > bSymbol ? 1 : 0
-        } else {
-          return 0
-        }
+        // -1 = a is first
+        // 1 = b is first
+
+        // sort ETH first
+        const a = allTokens[tokenAddressA]
+        const b = allTokens[tokenAddressB]
+        if (a.equals(WETH[chainId])) return -1
+        if (b.equals(WETH[chainId])) return 1
+
+        // sort by balances
+        const balanceA = allBalances[account]?.[tokenAddressA]
+        const balanceB = allBalances[account]?.[tokenAddressB]
+        if (balanceA?.greaterThan('0') && !balanceB?.greaterThan('0')) return !invertSearchOrder ? -1 : 1
+        if (!balanceA?.greaterThan('0') && balanceB?.greaterThan('0')) return !invertSearchOrder ? 1 : -1
+        if (balanceA?.greaterThan('0') && balanceB?.greaterThan('0')) {
+          return balanceA.greaterThan(balanceB) ? (!invertSearchOrder ? -1 : 1) : !invertSearchOrder ? 1 : -1
+        }
+
+        // sort by symbol
+        return a.symbol.toLowerCase() < b.symbol.toLowerCase() ? -1 : 1
       })
-      .filter(tokenAddress => isAddress(tokenAddress))
       .map(tokenAddress => {
+        const token = allTokens[tokenAddress]
         return {
-          name: allTokens[tokenAddress].name,
-          symbol: allTokens[tokenAddress].symbol,
-          address: isAddress(tokenAddress) as string, // always a string after filtering
+          name: token.name,
+          symbol: token.symbol,
+          address: isAddress(tokenAddress) as string,
           balance: allBalances?.[account]?.[tokenAddress]
         }
       })
-  }, [allTokens, allBalances, account, sortDirection, chainId])
+  }, [allTokens, chainId, allBalances, account, invertSearchOrder])
 
   const filteredTokenList = useMemo(() => {
     return tokenList.filter(tokenEntry => {
@@ -307,57 +307,69 @@ function SearchModal({
     onDismiss()
   }
 
+  // make an effort to identify the specific token a user is searching for
+  useEffect(() => {
+    const searchQueryIsAddress = !!isAddress(searchQuery)
+
+    // try to find an exact match by address
+    if (searchQueryIsAddress) {
+      const identifiedTokenByAddress = Object.values(allTokens).filter(token => {
+        if (searchQueryIsAddress && token.address === isAddress(searchQuery)) {
+          return true
+        }
+        return false
+      })
+      if (identifiedTokenByAddress.length > 0) setIdentifiedToken(identifiedTokenByAddress[0])
+    }
+    // try to find an exact match by symbol
+    else {
+      const identifiedTokenBySymbol = Object.values(allTokens).filter(token => {
+        if (token.symbol.slice(0, searchQuery.length).toLowerCase() === searchQuery.toLowerCase()) return true
+        return false
+      })
+      if (identifiedTokenBySymbol.length > 0) setIdentifiedToken(identifiedTokenBySymbol[0])
+    }
+
+    return () => {
+      setIdentifiedToken(undefined)
+    }
+  }, [allTokens, searchQuery])
+
   const sortedPairList = useMemo(() => {
     return allPairs.sort((a, b): number => {
       // sort by balance
-      const balanceA = allBalances?.[account]?.[a.liquidityToken.address]
-      const balanceB = allBalances?.[account]?.[b.liquidityToken.address]
-
-      if (balanceA?.greaterThan('0') && !balanceB?.greaterThan('0')) {
-        return sortDirection ? -1 : 1
+      const balanceA = allBalances[account]?.[a.liquidityToken.address]
+      const balanceB = allBalances[account]?.[b.liquidityToken.address]
+      if (balanceA?.greaterThan('0') && !balanceB?.greaterThan('0')) return !invertSearchOrder ? -1 : 1
+      if (!balanceA?.greaterThan('0') && balanceB?.greaterThan('0')) return !invertSearchOrder ? 1 : -1
+      if (balanceA?.greaterThan('0') && balanceB?.greaterThan('0')) {
+        return balanceA.greaterThan(balanceB) ? (!invertSearchOrder ? -1 : 1) : !invertSearchOrder ? 1 : -1
       }
-      if (!balanceA?.greaterThan('0') && balanceB?.greaterThan('0')) {
-        return sortDirection ? 1 : -1
-      } else {
       return 0
-      }
     })
-  }, [account, allBalances, allPairs, sortDirection])
+  }, [allPairs, allBalances, account, invertSearchOrder])
 
   const filteredPairList = useMemo(() => {
-    const isAddress = searchQuery.slice(0, 2) === '0x'
+    const searchQueryIsAddress = !!isAddress(searchQuery)
     return sortedPairList.filter(pair => {
-      if (searchQuery === '') {
-        return true
-      }
+      // if there's no search query, hide non-ETH pairs
+      if (searchQuery === '') return pair.token0.equals(WETH[chainId]) || pair.token1.equals(WETH[chainId])
+
       const token0 = pair.token0
       const token1 = pair.token1
-      if (!token0 || !token1) {
-        return false // no token fetched yet
+
+      if (searchQueryIsAddress) {
+        if (token0.address === isAddress(searchQuery)) return true
+        if (token1.address === isAddress(searchQuery)) return true
       } else {
-        const regexMatches = Object.keys(token0).map(field => {
-          if (
-            (field === 'address' && isAddress) ||
-            (field === 'name' && !isAddress) ||
-            (field === 'symbol' && !isAddress)
-          ) {
-            if (token0[field].match(new RegExp(escapeRegExp(searchQuery), 'i'))) {
-              setIdentifiedToken(token0)
-            }
-            if (token1[field].match(new RegExp(escapeRegExp(searchQuery), 'i'))) {
-              setIdentifiedToken(token1)
-            }
-            return (
-              token0[field].match(new RegExp(escapeRegExp(searchQuery), 'i')) ||
-              token1[field].match(new RegExp(escapeRegExp(searchQuery), 'i'))
-            )
+        const identifier0 = `${token0.symbol}/${token1.symbol}`
+        const identifier1 = `${token1.symbol}/${token0.symbol}`
+        if (identifier0.slice(0, searchQuery.length).toLowerCase() === searchQuery.toLowerCase()) return true
+        if (identifier1.slice(0, searchQuery.length).toLowerCase() === searchQuery.toLowerCase()) return true
       }
       return false
     })
-        return regexMatches.some(m => m)
-      }
-    })
-  }, [searchQuery, sortedPairList])
+  }, [searchQuery, sortedPairList, chainId])
 
   function renderPairsList() {
     if (filteredPairList?.length === 0) {
@@ -441,21 +453,7 @@ function SearchModal({
         return <TokenModalInfo>{t('noToken')}</TokenModalInfo>
       }
     } else {
-      return filteredTokenList
-        .sort((a, b) => {
-          if (a.address === WETH[chainId].address) {
-            return -1
-          } else if (b.address === WETH[chainId].address) {
-            return 1
-          } else if (a.balance?.greaterThan('0') && !b.balance?.greaterThan('0')) {
-            return sortDirection ? -1 : 1
-          } else if (!a.balance?.greaterThan('0') && b.balance?.greaterThan('0')) {
-            return sortDirection ? 1 : -1
-          } else {
-            return sortDirection ? -1 : 1
-          }
-        })
-        .map(({ address, symbol, balance }) => {
+      return filteredTokenList.map(({ address, symbol, balance }) => {
         const urlAdded = urlAddedTokens?.some(token => token.address === address)
         const customAdded = userAddedTokens?.some(token => token.address === address) && !urlAdded
 
@@ -530,7 +528,7 @@ function SearchModal({
       <FilterWrapper
         onClick={() => {
           setActiveFilter(filter)
-          setSortDirection(!sortDirection)
+          setInvertSearchOrder(invertSearchOrder => !invertSearchOrder)
         }}
         selected={filter === activeFilter}
       >
@@ -539,7 +537,7 @@ function SearchModal({
         </Text>
         {filter === activeFilter && filterType === 'tokens' && (
           <Text fontSize={14} fontWeight={500}>
-            {sortDirection ? '↓' : '↑'}
+            {!invertSearchOrder ? '↓' : '↑'}
           </Text>
         )}
       </FilterWrapper>

src/components/WalletModal/index.tsx

@@ -2,7 +2,8 @@ import React, { useState, useEffect } from 'react'
 import ReactGA from 'react-ga'
 import styled from 'styled-components'
 import { isMobile } from 'react-device-detect'
-import { useWeb3React, UnsupportedChainIdError } from '@web3-react/core'
+import { UnsupportedChainIdError } from '@web3-react/core'
+import { useWeb3React } from '../../hooks'
 import { URI_AVAILABLE } from '@web3-react/walletconnect-connector'
 import { useWalletModalOpen, useWalletModalToggle } from '../../state/application/hooks'
 

src/components/swap/V1TradeLink.tsx

-import { Trade } from '@uniswap/sdk'
 import React, { useContext } from 'react'
 import { Text } from 'rebass'
 import { ThemeContext } from 'styled-components'
-import { V1_TRADE_LINK_THRESHOLD } from '../../constants'
-import { useV1TradeLinkIfBetter } from '../../data/V1'
+
 import { Link } from '../../theme'
 import { YellowCard } from '../Card'
 import { AutoColumn } from '../Column'
 
-export default function V1TradeLink({ bestV2Trade }: { bestV2Trade?: Trade }) {
-  const v1TradeLinkIfBetter = useV1TradeLinkIfBetter(bestV2Trade, V1_TRADE_LINK_THRESHOLD)
+export default function V1TradeLink({ v1TradeLinkIfBetter }: { v1TradeLinkIfBetter: string }) {
   const theme = useContext(ThemeContext)
   return v1TradeLinkIfBetter ? (
     <YellowCard style={{ marginTop: '12px', padding: '8px 4px' }}>

src/connectors/index.ts

@@ -15,7 +15,7 @@ export const network = new NetworkConnector({
 })
 
 export const injected = new InjectedConnector({
-  supportedChainIds: [3, 4, 5, 42]
+  supportedChainIds: [1, 3, 4, 5, 42]
 })
 
 // mainnet only

src/constants/tokens/kovan.ts

+import { Token, ChainId } from '@uniswap/sdk'
+
+export default [
+  new Token(ChainId.KOVAN, '0x4F96Fe3b7A6Cf9725f59d353F723c1bDb64CA6Aa', 18, 'DAI', 'Dai Stablecoin'),
+  new Token(ChainId.KOVAN, '0xAaF64BFCC32d0F15873a02163e7E500671a4ffcD', 18, 'MKR', 'Maker')
+]

src/constants/tokens/rinkeby.ts

+import { Token, ChainId } from '@uniswap/sdk'
+
+export default [
+  new Token(ChainId.RINKEBY, '0xc7AD46e0b8a400Bb3C915120d284AafbA8fc4735', 18, 'DAI', 'Dai Stablecoin'),
+  new Token(ChainId.RINKEBY, '0xF9bA5210F91D0474bd1e1DcDAeC4C58E359AaD85', 18, 'MKR', 'Maker')
+]

src/constants/tokens/ropsten.ts

+import { Token, ChainId } from '@uniswap/sdk'
+
+export default [new Token(ChainId.ROPSTEN, '0xaD6D458402F60fD3Bd25163575031ACDce07538D', 18, 'DAI', 'Dai Stablecoin')]

src/data/V1.ts

 import { Contract } from '@ethersproject/contracts'
 import { Token, TokenAmount, Pair, Trade, ChainId, WETH, Route, TradeType, Percent } from '@uniswap/sdk'
 import useSWR from 'swr'
-import { useWeb3React } from '@web3-react/core'
+import { useWeb3React } from '../hooks'
 
 import IUniswapV1Factory from '../constants/abis/v1_factory.json'
 import { V1_FACTORY_ADDRESS } from '../constants'
@@ -41,49 +41,63 @@ function useMockV1Pair(token?: Token) {
     : undefined
 }
 
-export function useV1TradeLinkIfBetter(trade: Trade, minimumDelta: Percent = new Percent('0')): string {
-  const inputPair = useMockV1Pair(trade?.route?.input)
-  const outputPair = useMockV1Pair(trade?.route?.output)
+export function useV1TradeLinkIfBetter(
+  isExactIn: boolean,
+  inputToken: Token,
+  outputToken: Token,
+  exactAmount: TokenAmount,
+  v2Trade: Trade,
+  minimumDelta: Percent = new Percent('0')
+): string {
+  const { chainId } = useWeb3React()
+
+  const input = inputToken
+  const output = outputToken
+  const mainnet = chainId === ChainId.MAINNET
+
+  // get the mock v1 pairs
+  const inputPair = useMockV1Pair(input)
+  const outputPair = useMockV1Pair(output)
 
-  const mainnet = trade?.route?.input?.chainId === ChainId.MAINNET
-  const inputIsWETH = mainnet && trade?.route?.input?.equals(WETH[ChainId.MAINNET])
-  const outputIsWETH = mainnet && trade?.route?.output?.equals(WETH[ChainId.MAINNET])
-  const neitherWETH = mainnet && !!trade && !inputIsWETH && !outputIsWETH
+  const inputIsWETH = mainnet && input?.equals(WETH[ChainId.MAINNET])
+  const outputIsWETH = mainnet && output?.equals(WETH[ChainId.MAINNET])
 
+  // construct a direct or through ETH v1 route
   let pairs: Pair[]
   if (inputIsWETH && outputPair) {
     pairs = [outputPair]
   } else if (outputIsWETH && inputPair) {
     pairs = [inputPair]
-  } else if (neitherWETH && inputPair && outputPair) {
+  }
+  // if neither are WETH, it's token-to-token (if they both exist)
+  else if (inputPair && outputPair) {
     pairs = [inputPair, outputPair]
   }
 
-  const route = pairs && new Route(pairs, trade.route.input)
+  const route = pairs && new Route(pairs, input)
   const v1Trade =
-    route &&
-    new Trade(
-      route,
-      trade.tradeType === TradeType.EXACT_INPUT ? trade.inputAmount : trade.outputAmount,
-      trade.tradeType
-    )
+    route && exactAmount
+      ? new Trade(route, exactAmount, isExactIn ? TradeType.EXACT_INPUT : TradeType.EXACT_OUTPUT)
+      : undefined
 
   let v1HasBetterTrade = false
   if (v1Trade) {
-    if (trade.tradeType === TradeType.EXACT_INPUT) {
-      // check if the output amount on v1, discounted by minimumDelta, is greater than on v2
-      const discountedV1Output = v1Trade.outputAmount.multiply(new Percent('1').subtract(minimumDelta))
-      v1HasBetterTrade = discountedV1Output.greaterThan(trade.outputAmount)
+    if (isExactIn) {
+      // discount the v1 output amount by minimumDelta
+      const discountedV1Output = v1Trade?.outputAmount.multiply(new Percent('1').subtract(minimumDelta))
+      // check if the discounted v1 amount is still greater than v2, short-circuiting if no v2 trade exists
+      v1HasBetterTrade = !!!v2Trade || discountedV1Output.greaterThan(v2Trade.outputAmount)
     } else {
-      // check if the input amount on v1, inflated by minimumDelta, is less than on v2
-      const inflatedV1Input = v1Trade.inputAmount.multiply(new Percent('1').add(minimumDelta))
-      v1HasBetterTrade = inflatedV1Input.lessThan(trade.inputAmount)
+      // inflate the v1 amount by minimumDelta
+      const inflatedV1Input = v1Trade?.inputAmount.multiply(new Percent('1').add(minimumDelta))
+      // check if the inflated v1 amount is still less than v2, short-circuiting if no v2 trade exists
+      v1HasBetterTrade = !!!v2Trade || inflatedV1Input.lessThan(v2Trade.inputAmount)
     }
   }
 
   return v1HasBetterTrade
-    ? `https://v1.uniswap.exchange/swap?inputCurrency=${
-        inputIsWETH ? 'ETH' : trade.route.input.address
-      }&outputCurrency=${outputIsWETH ? 'ETH' : trade.route.output.address}`
+    ? `https://v1.uniswap.exchange/swap?inputCurrency=${inputIsWETH ? 'ETH' : input.address}&outputCurrency=${
+        outputIsWETH ? 'ETH' : output.address
+      }`
     : undefined
 }

src/hooks/Tokens.ts

-import { ChainId, Token, WETH } from '@uniswap/sdk'
+import { Token, WETH } from '@uniswap/sdk'
 import { useEffect, useMemo } from 'react'
 import { useAddUserToken, useFetchTokenByAddress, useUserAddedTokens } from '../state/user/hooks'
+
 import { useWeb3React } from './index'
+import MAINNET_TOKENS from '../constants/tokens/mainnet'
+import RINKEBY_TOKENS from '../constants/tokens/rinkeby'
+import KOVAN_TOKENS from '../constants/tokens/kovan'
+import ROPSTEN_TOKENS from '../constants/tokens/ropsten'
 
 export const ALL_TOKENS = [
   // WETH on all chains
   ...Object.values(WETH),
-
-  // Mainnet Tokens
-  new Token(ChainId.MAINNET, '0x6B175474E89094C44Da98b954EedeAC495271d0F', 18, 'DAI', 'Dai Stablecoin'),
-  new Token(ChainId.MAINNET, '0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48', 6, 'USDC', 'USD//C'),
-  new Token(ChainId.MAINNET, '0x9f8F72aA9304c8B593d555F12eF6589cC3A579A2', 18, 'MKR', 'Maker'),
-
-  // Rinkeby Tokens
-  new Token(ChainId.RINKEBY, '0xc7AD46e0b8a400Bb3C915120d284AafbA8fc4735', 18, 'DAI', 'Dai Stablecoin'),
-  new Token(ChainId.RINKEBY, '0xF9bA5210F91D0474bd1e1DcDAeC4C58E359AaD85', 18, 'MKR', 'Maker'),
-
-  // Kovan Tokens
-  new Token(ChainId.KOVAN, '0x4F96Fe3b7A6Cf9725f59d353F723c1bDb64CA6Aa', 18, 'DAI', 'Dai Stablecoin'),
-  new Token(ChainId.KOVAN, '0xAaF64BFCC32d0F15873a02163e7E500671a4ffcD', 18, 'MKR', 'Maker'),
-
-  // Ropsten Tokens
-  new Token(ChainId.ROPSTEN, '0xaD6D458402F60fD3Bd25163575031ACDce07538D', 18, 'DAI', 'Dai Stablecoin')
-
-  // Goerli Tokens
+  // chain-specific tokens
+  ...MAINNET_TOKENS,
+  ...RINKEBY_TOKENS,
+  ...KOVAN_TOKENS,
+  ...ROPSTEN_TOKENS
 ]
   // remap WETH to ETH
   .map(token => {

src/hooks/Trades.ts

@@ -23,15 +23,23 @@ function useAllCommonPairs(tokenA?: Token, tokenB?: Token): Pair[] {
   const aToUSDC = usePair(tokenA, chainId === ChainId.MAINNET ? USDC : null)
   const bToUSDC = usePair(tokenB, chainId === ChainId.MAINNET ? USDC : null)
 
-  return useMemo(() => [pairBetween, aToETH, bToETH, aToDAI, bToDAI, aToUSDC, bToUSDC].filter(p => !!p), [
-    pairBetween,
-    aToETH,
-    bToETH,
-    aToDAI,
-    bToDAI,
-    aToUSDC,
-    bToUSDC
-  ])
+  // get connecting pairs
+  const DAIToETH = usePair(chainId === ChainId.MAINNET ? DAI : null, WETH[chainId])
+  const USDCToETH = usePair(chainId === ChainId.MAINNET ? USDC : null, WETH[chainId])
+  const DAIToUSDC = usePair(chainId === ChainId.MAINNET ? DAI : null, chainId === ChainId.MAINNET ? USDC : null)
+
+  // only pass along valid pairs, non-duplicated pairs
+  return useMemo(
+    () =>
+      [pairBetween, aToETH, bToETH, aToDAI, bToDAI, aToUSDC, bToUSDC, DAIToETH, USDCToETH, DAIToUSDC]
+        // filter out invalid pairs
+        .filter(p => !!p)
+        // filter out duplicated pairs
+        .filter(
+          (p, i, pairs) => i === pairs.findIndex(pair => pair?.liquidityToken.address === p.liquidityToken.address)
+        ),
+    [pairBetween, aToETH, bToETH, aToDAI, bToDAI, aToUSDC, bToUSDC, DAIToETH, USDCToETH, DAIToUSDC]
+  )
 }
 
 /**

src/pages/Pool/index.tsx

@@ -14,7 +14,7 @@ import { RowBetween } from '../../components/Row'
 import { ButtonPrimary, ButtonSecondary } from '../../components/Button'
 import { AutoColumn, ColumnCenter } from '../../components/Column'
 
-import { useWeb3React } from '@web3-react/core'
+import { useWeb3React } from '../../hooks'
 import { usePair } from '../../data/Reserves'
 import { useAllDummyPairs } from '../../state/user/hooks'
 

src/pages/Send/index.tsx

@@ -39,10 +39,9 @@ import { useDefaultsFromURL, useDerivedSwapInfo, useSwapActionHandlers, useSwapS
 import { useHasPendingApproval } from '../../state/transactions/hooks'
 import { useAllTokenBalancesTreatingWETHasETH } from '../../state/wallet/hooks'
 import { CursorPointer, TYPE } from '../../theme'
-import { Link } from '../../theme/components'
 import { computeSlippageAdjustedAmounts, computeTradePriceBreakdown, warningServerity } from '../../utils/prices'
 
-export default function Send({ history, location: { search } }: RouteComponentProps) {
+export default function Send({ location: { search } }: RouteComponentProps) {
   useDefaultsFromURL(search)
 
   // text translation
@@ -61,7 +60,14 @@ export default function Send({ history, location: { search } }: RouteComponentPr
 
   // trade details, check query params for initial state
   const { independentField, typedValue } = useSwapState()
-  const { parsedAmounts, bestTrade, tokenBalances, tokens, error: swapError } = useDerivedSwapInfo()
+  const {
+    parsedAmounts,
+    bestTrade,
+    tokenBalances,
+    tokens,
+    error: swapError,
+    v1TradeLinkIfBetter
+  } = useDerivedSwapInfo()
   const isSwapValid = !swapError && !recipientError && bestTrade
 
   const dependentField: Field = independentField === Field.INPUT ? Field.OUTPUT : Field.INPUT
@@ -474,13 +480,6 @@ export default function Send({ history, location: { search } }: RouteComponentPr
         ) : noRoute && userHasSpecifiedInputOutput ? (
           <GreyCard style={{ textAlign: 'center' }}>
             <TYPE.main mb="4px">Insufficient liquidity for this trade.</TYPE.main>
-            <Link
-              onClick={() => {
-                history.push('/add/' + tokens[Field.INPUT]?.address + '-' + tokens[Field.OUTPUT]?.address)
-              }}
-            >
-              Add liquidity now.
-            </Link>
           </GreyCard>
         ) : mustApprove === true ? (
           <ButtonLight onClick={approveCallback} disabled={pendingApprovalInput}>
@@ -507,7 +506,7 @@ export default function Send({ history, location: { search } }: RouteComponentPr
             </Text>
           </ButtonError>
         )}
-        <V1TradeLink bestV2Trade={bestTrade} />
+        <V1TradeLink v1TradeLinkIfBetter={v1TradeLinkIfBetter} />
       </BottomGrouping>
       {bestTrade && (
         <AdvancedSwapDetailsDropdown

src/pages/Swap/index.tsx

@@ -25,11 +25,11 @@ import { useWalletModalToggle } from '../../state/application/hooks'
 import { Field } from '../../state/swap/actions'
 import { useDefaultsFromURL, useDerivedSwapInfo, useSwapActionHandlers, useSwapState } from '../../state/swap/hooks'
 import { useHasPendingApproval } from '../../state/transactions/hooks'
-import { CursorPointer, Link, TYPE } from '../../theme'
+import { CursorPointer, TYPE } from '../../theme'
 import { computeSlippageAdjustedAmounts, computeTradePriceBreakdown, warningServerity } from '../../utils/prices'
 import SwapModalHeader from '../../components/swap/SwapModalHeader'
 
-export default function Swap({ history, location: { search } }: RouteComponentProps) {
+export default function Swap({ location: { search } }: RouteComponentProps) {
   useDefaultsFromURL(search)
   // text translation
   // const { t } = useTranslation()
@@ -40,7 +40,7 @@ export default function Swap({ history, location: { search } }: RouteComponentPr
   const toggleWalletModal = useWalletModalToggle()
 
   const { independentField, typedValue } = useSwapState()
-  const { bestTrade, tokenBalances, parsedAmounts, tokens, error } = useDerivedSwapInfo()
+  const { bestTrade, tokenBalances, parsedAmounts, tokens, error, v1TradeLinkIfBetter } = useDerivedSwapInfo()
   const isValid = !error
   const dependentField: Field = independentField === Field.INPUT ? Field.OUTPUT : Field.INPUT
 
@@ -277,14 +277,6 @@ export default function Swap({ history, location: { search } }: RouteComponentPr
         ) : noRoute && userHasSpecifiedInputOutput ? (
           <GreyCard style={{ textAlign: 'center' }}>
             <TYPE.main mb="4px">Insufficient liquidity for this trade.</TYPE.main>
-            <Link
-              onClick={() => {
-                history.push('/add/' + tokens[Field.INPUT]?.address + '-' + tokens[Field.OUTPUT]?.address)
-              }}
-            >
-              {' '}
-              Add liquidity now.
-            </Link>
           </GreyCard>
         ) : mustApprove === true ? (
           <ButtonLight onClick={approveCallback} disabled={pendingApprovalInput}>
@@ -308,7 +300,7 @@ export default function Swap({ history, location: { search } }: RouteComponentPr
             </Text>
           </ButtonError>
         )}
-        <V1TradeLink bestV2Trade={bestTrade} />
+        <V1TradeLink v1TradeLinkIfBetter={v1TradeLinkIfBetter} />
       </BottomGrouping>
       {bestTrade && (
         <AdvancedSwapDetailsDropdown

src/state/swap/hooks.ts

@@ -8,6 +8,8 @@ import { useTradeExactIn, useTradeExactOut } from '../../hooks/Trades'
 import { AppDispatch, AppState } from '../index'
 import { useTokenBalancesTreatWETHAsETH } from '../wallet/hooks'
 import { Field, selectToken, setDefaultsFromURL, switchTokens, typeInput } from './actions'
+import { useV1TradeLinkIfBetter } from '../../data/V1'
+import { V1_TRADE_LINK_THRESHOLD } from '../../constants'
 
 export function useSwapState(): AppState['swap'] {
   return useSelector<AppState, AppState['swap']>(state => state.swap)
@@ -68,6 +70,7 @@ export function useDerivedSwapInfo(): {
   parsedAmounts: { [field in Field]?: TokenAmount }
   bestTrade?: Trade
   error?: string
+  v1TradeLinkIfBetter?: string
 } {
   const { account } = useWeb3React()
 
@@ -106,6 +109,16 @@ export function useDerivedSwapInfo(): {
     [Field.OUTPUT]: tokenOut
   }
 
+  // get link to trade on v1, if a better rate exists
+  const v1TradeLinkIfBetter = useV1TradeLinkIfBetter(
+    isExactIn,
+    tokens[Field.INPUT],
+    tokens[Field.OUTPUT],
+    isExactIn ? parsedAmounts[Field.INPUT] : parsedAmounts[Field.OUTPUT],
+    bestTrade,
+    V1_TRADE_LINK_THRESHOLD
+  )
+
   let error: string | undefined
   if (!account) {
     error = 'Connect Wallet'
@@ -132,7 +145,8 @@ export function useDerivedSwapInfo(): {
     tokenBalances,
     parsedAmounts,
     bestTrade,
-    error
+    error,
+    v1TradeLinkIfBetter
   }
 }
 

src/state/user/hooks.tsx

 import { ChainId, JSBI, Pair, Token, TokenAmount, WETH } from '@uniswap/sdk'
-import { useWeb3React } from '@web3-react/core'
+import { useWeb3React } from '../../hooks'
 import { useCallback, useMemo } from 'react'
 import { shallowEqual, useDispatch, useSelector } from 'react-redux'
 import { useAllTokens } from '../../hooks/Tokens'