feat: account suspense (#7337)

* feat: eagerly connect outside of react lifecycle

* test: reflect selected wallet in localStorage

* test: spy only on portfolio balances

* feat: connectionReady

* feat: connecting state

* feat: leave space for address

* fix tests

* better meta

* fix

* fix wallet change

* add interactivity earlier

* add validation

* update localstorage key in cypress setup

* even less thrash

* load per account

* simplify, hopefully

* explanatory

* inf render

* whoopsie

* ordering

cypress/utils/user-state.ts

@@ -1,3 +1,4 @@
+import { connectionMetaKey } from '../../src/connection/meta'
 import { ConnectionType } from '../../src/connection/types'
 import { UserState } from '../../src/state/user/reducer'
 
@@ -13,7 +14,12 @@ export const DISCONNECTED_WALLET_USER_STATE: Partial<UserState> = { selectedWall
 export function setInitialUserState(win: Cypress.AUTWindow, state: UserState) {
   // Selected wallet should also be reflected in localStorage, so that eager connections work.
   if (state.selectedWallet) {
-    win.localStorage.setItem('selected_wallet', state.selectedWallet)
+    win.localStorage.setItem(
+      connectionMetaKey,
+      JSON.stringify({
+        type: state.selectedWallet,
+      })
+    )
   }
 
   win.indexedDB.deleteDatabase('redux')

src/components/Web3Status/index.tsx

@@ -4,17 +4,19 @@ import { useWeb3React } from '@web3-react/core'
 import { sendAnalyticsEvent, TraceEvent } from 'analytics'
 import PortfolioDrawer, { useAccountDrawer } from 'components/AccountDrawer'
 import { usePendingActivity } from 'components/AccountDrawer/MiniPortfolio/Activity/hooks'
-import Loader from 'components/Icons/LoadingSpinner'
+import Loader, { LoaderV3 } from 'components/Icons/LoadingSpinner'
 import { IconWrapper } from 'components/Identicon/StatusIcon'
 import PrefetchBalancesWrapper from 'components/PrefetchBalancesWrapper/PrefetchBalancesWrapper'
 import { getConnection } from 'connection'
+import { useConnectionReady } from 'connection/eagerlyConnect'
+import { ConnectionMeta, getPersistedConnectionMeta, setPersistedConnectionMeta } from 'connection/meta'
 import useENSName from 'hooks/useENSName'
 import useLast from 'hooks/useLast'
 import { navSearchInputVisibleSize } from 'hooks/useScreenSize'
 import { Portal } from 'nft/components/common/Portal'
 import { useIsNftClaimAvailable } from 'nft/hooks/useIsNftClaimAvailable'
 import { darken } from 'polished'
-import { useCallback } from 'react'
+import { useCallback, useEffect, useMemo, useRef } from 'react'
 import { useAppSelector } from 'state/hooks'
 import styled from 'styled-components'
 import { colors } from 'theme/colors'
@@ -94,8 +96,15 @@ const Web3StatusConnected = styled(Web3StatusGeneric)<{
   }
 `
 
-const AddressAndChevronContainer = styled.div`
+const Web3StatusConnecting = styled(Web3StatusConnected)`
+  &:disabled {
+    opacity: 1;
+  }
+`
+
+const AddressAndChevronContainer = styled.div<{ loading?: boolean }>`
   display: flex;
+  opacity: ${({ loading, theme }) => loading && theme.opacity.disabled};
 
   @media only screen and (max-width: ${navSearchInputVisibleSize}px) {
     display: none;
@@ -128,8 +137,11 @@ const StyledConnectButton = styled.button`
 function Web3StatusInner() {
   const switchingChain = useAppSelector((state) => state.wallets.switchingChain)
   const ignoreWhileSwitchingChain = useCallback(() => !switchingChain, [switchingChain])
-  const { account, connector } = useLast(useWeb3React(), ignoreWhileSwitchingChain)
+  const connectionReady = useConnectionReady()
-  const { ENSName } = useENSName(account)
+  const activeWeb3 = useWeb3React()
+  const lastWeb3 = useLast(useWeb3React(), ignoreWhileSwitchingChain)
+  const { account, connector } = useMemo(() => (activeWeb3.account ? activeWeb3 : lastWeb3), [activeWeb3, lastWeb3])
+  const { ENSName, loading: ENSLoading } = useENSName(account)
   const connection = getConnection(connector)
 
   const [, toggleAccountDrawer] = useAccountDrawer()
@@ -141,6 +153,48 @@ function Web3StatusInner() {
 
   const { hasPendingActivity, pendingActivityCount } = usePendingActivity()
 
+  // Display a loading state while initializing the connection, based on the last session's persisted connection.
+  // The connection will go through three states:
+  // - startup:       connection is not ready
+  // - initializing:  account is available, but ENS (if preset on the persisted initialMeta) is still loading
+  // - initialized:   account and ENS are available
+  // Subsequent connections are always considered initialized, and will not display startup/initializing states.
+  const initialConnection = useRef(getPersistedConnectionMeta())
+  const isConnectionInitializing = Boolean(
+    initialConnection.current?.address === account && initialConnection.current?.ENSName && ENSLoading
+  )
+  const isConnectionInitialized = connectionReady && !isConnectionInitializing
+  // Clear the initial connection once initialized so it does not interfere with subsequent connections.
+  useEffect(() => {
+    if (isConnectionInitialized) {
+      initialConnection.current = undefined
+    }
+  }, [isConnectionInitialized])
+  // Persist the connection if it changes, so it can be used to initialize the next session's connection.
+  useEffect(() => {
+    if (account || ENSName) {
+      const meta: ConnectionMeta = {
+        type: connection.type,
+        address: account,
+        ENSName: ENSName ?? undefined,
+      }
+      setPersistedConnectionMeta(meta)
+    }
+  }, [ENSName, account, connection.type])
+
+  if (!isConnectionInitialized) {
+    return (
+      <Web3StatusConnecting disabled={!isConnectionInitializing} onClick={handleWalletDropdownClick}>
+        <IconWrapper size={24}>
+          <LoaderV3 size="24px" />
+        </IconWrapper>
+        <AddressAndChevronContainer loading={true}>
+          <Text>{initialConnection.current?.ENSName ?? shortenAddress(initialConnection.current?.address)}</Text>
+        </AddressAndChevronContainer>
+      </Web3StatusConnecting>
+    )
+  }
+
   if (account) {
     return (
       <TraceEvent
@@ -167,7 +221,7 @@ function Web3StatusInner() {
             </RowBetween>
           ) : (
             <AddressAndChevronContainer>
-              <Text>{ENSName || shortenAddress(account)}</Text>
+              <Text>{ENSName ?? shortenAddress(account)}</Text>
             </AddressAndChevronContainer>
           )}
         </Web3StatusConnected>

src/connection/eagerlyConnect.ts

@@ -1,7 +1,25 @@
 import { Connector } from '@web3-react/types'
+import { useSyncExternalStore } from 'react'
 
 import { getConnection, gnosisSafeConnection, networkConnection } from './index'
-import { ConnectionType, selectedWalletKey, toConnectionType } from './types'
+import { deletePersistedConnectionMeta, getPersistedConnectionMeta } from './meta'
+import { ConnectionType } from './types'
+
+class FailedToConnect extends Error {}
+
+let connectionReady: Promise<void> | true = true
+
+export function useConnectionReady() {
+  return useSyncExternalStore(
+    (onStoreChange) => {
+      if (connectionReady instanceof Promise) {
+        connectionReady.finally(onStoreChange)
+      }
+      return () => undefined
+    },
+    () => connectionReady === true
+  )
+}
 
 async function connect(connector: Connector, type: ConnectionType) {
   performance.mark(`web3:connect:${type}:start`)
@@ -28,15 +46,25 @@ if (window !== window.parent) {
 
 connect(networkConnection.connector, ConnectionType.NETWORK)
 
-const selectedWallet = toConnectionType(localStorage.getItem(selectedWalletKey) ?? undefined)
+// Get the persisted wallet type from the last session.
-if (selectedWallet) {
+const meta = getPersistedConnectionMeta()
-  const selectedConnection = getConnection(selectedWallet)
+if (meta?.type) {
+  const selectedConnection = getConnection(meta.type)
   if (selectedConnection) {
-    connect(selectedConnection.connector, selectedWallet).then((connected) => {
+    connectionReady = connect(selectedConnection.connector, meta.type)
-      if (!connected) {
+      .then((connected) => {
-        // only clear the persisted wallet type if it failed to connect.
+        if (!connected) throw new FailedToConnect()
-        localStorage.removeItem(selectedWalletKey)
+      })
-      }
+      .catch((error) => {
-    })
+        // Clear the persisted wallet type if it failed to connect.
+        deletePersistedConnectionMeta()
+        // Log it if it threw an unknown error.
+        if (!(error instanceof FailedToConnect)) {
+          console.error(error)
+        }
+      })
+      .finally(() => {
+        connectionReady = true
+      })
   }
 }

src/connection/meta.ts

@@ -0,0 +1,37 @@
+import { ConnectionType, toConnectionType } from './types'
+
+export interface ConnectionMeta {
+  type: ConnectionType
+  address?: string
+  ENSName?: string
+}
+
+export const connectionMetaKey = 'connection_meta'
+
+export function getPersistedConnectionMeta(): ConnectionMeta | undefined {
+  try {
+    const value = localStorage.getItem(connectionMetaKey)
+    if (value) {
+      const raw = JSON.parse(value) as ConnectionMeta
+      const connectionType = toConnectionType(raw.type)
+      if (connectionType) {
+        return {
+          type: connectionType,
+          address: raw.address,
+          ENSName: raw.ENSName,
+        }
+      }
+    }
+  } catch (e) {
+    console.warn(e)
+  }
+  return
+}
+
+export function setPersistedConnectionMeta(meta: ConnectionMeta) {
+  localStorage.setItem(connectionMetaKey, JSON.stringify(meta))
+}
+
+export function deletePersistedConnectionMeta() {
+  localStorage.removeItem(connectionMetaKey)
+}

src/connection/types.ts

@@ -2,8 +2,6 @@ import { ChainId } from '@uniswap/sdk-core'
 import { Web3ReactHooks } from '@web3-react/core'
 import { Connector } from '@web3-react/types'
 
-export const selectedWalletKey = 'selected_wallet'
-
 export enum ConnectionType {
   UNISWAP_WALLET_V2 = 'UNISWAP_WALLET_V2',
   INJECTED = 'INJECTED',

src/hooks/useENSName.ts

@@ -34,11 +34,12 @@ export default function useENSName(address?: string): { ENSName: string | null;
   const checkedName = address === fwdAddr?.address ? name : null
 
   const changed = debouncedAddress !== address
+  const loading = changed || resolverAddress.loading || nameCallRes.loading || fwdAddr.loading
   return useMemo(
     () => ({
       ENSName: changed ? null : checkedName,
-      loading: changed || resolverAddress.loading || nameCallRes.loading,
+      loading,
     }),
-    [changed, nameCallRes.loading, checkedName, resolverAddress.loading]
+    [changed, checkedName, loading]
   )
 }

src/pages/Swap/index.tsx

@@ -29,6 +29,7 @@ import SwapDetailsDropdown from 'components/swap/SwapDetailsDropdown'
 import SwapHeader from 'components/swap/SwapHeader'
 import { SwitchLocaleLink } from 'components/SwitchLocaleLink'
 import TokenSafetyModal from 'components/TokenSafety/TokenSafetyModal'
+import { useConnectionReady } from 'connection/eagerlyConnect'
 import { getChainInfo } from 'constants/chainInfo'
 import { asSupportedChain, isSupportedChain } from 'constants/chains'
 import { getSwapCurrencyId, TOKEN_SHORTHANDS } from 'constants/tokens'
@@ -183,6 +184,7 @@ export function Swap({
   onCurrencyChange?: (selected: Pick<SwapState, Field.INPUT | Field.OUTPUT>) => void
   disableTokenInputs?: boolean
 }) {
+  const connectionReady = useConnectionReady()
   const { account, chainId: connectedChainId, connector } = useWeb3React()
   const trace = useTrace()
 
@@ -723,7 +725,7 @@ export function Swap({
             <ButtonPrimary $borderRadius="16px" disabled={true}>
               <Trans>Connecting to {getChainInfo(switchingChain)?.label}</Trans>
             </ButtonPrimary>
-          ) : !account ? (
+          ) : connectionReady && !account ? (
             <TraceEvent
               events={[BrowserEvent.onClick]}
               name={InterfaceEventName.CONNECT_WALLET_BUTTON_CLICKED}

src/setupTests.ts

@@ -74,6 +74,12 @@ jest.mock('@web3-react/core', () => {
   }
 })
 
+jest.mock('connection/eagerlyConnect', () => {
+  return {
+    useConnectionReady: () => true,
+  }
+})
+
 jest.mock('state/routing/slice', () => {
   const routingSlice = jest.requireActual('state/routing/slice')
   return {

src/state/swap/hooks.tsx

@@ -1,6 +1,7 @@
 import { Trans } from '@lingui/macro'
 import { ChainId, Currency, CurrencyAmount, Percent, TradeType } from '@uniswap/sdk-core'
 import { useWeb3React } from '@web3-react/core'
+import { useConnectionReady } from 'connection/eagerlyConnect'
 import { useFotAdjustmentsEnabled } from 'featureFlags/flags/fotAdjustments'
 import useAutoSlippageTolerance from 'hooks/useAutoSlippageTolerance'
 import { useDebouncedTrade } from 'hooks/useDebouncedTrade'
@@ -168,11 +169,12 @@ export function useDerivedSwapInfo(state: SwapState, chainId: ChainId | undefine
   // slippage amount used to submit the trade
   const allowedSlippage = uniswapXAutoSlippage ?? classicAllowedSlippage
 
+  const connectionReady = useConnectionReady()
   const inputError = useMemo(() => {
     let inputError: ReactNode | undefined
 
     if (!account) {
-      inputError = <Trans>Connect Wallet</Trans>
+      inputError = connectionReady ? <Trans>Connect Wallet</Trans> : <Trans>Connecting Wallet...</Trans>
     }
 
     if (!currencies[Field.INPUT] || !currencies[Field.OUTPUT]) {
@@ -200,7 +202,7 @@ export function useDerivedSwapInfo(state: SwapState, chainId: ChainId | undefine
     }
 
     return inputError
-  }, [account, currencies, parsedAmount, to, currencyBalances, trade.trade, allowedSlippage])
+  }, [account, currencies, parsedAmount, to, currencyBalances, trade?.trade, allowedSlippage, connectionReady])
 
   return useMemo(
     () => ({

src/state/user/reducer.ts

@@ -1,12 +1,13 @@
 import { createSlice } from '@reduxjs/toolkit'
+import { deletePersistedConnectionMeta, getPersistedConnectionMeta } from 'connection/meta'
 
-import { ConnectionType, selectedWalletKey, toConnectionType } from '../../connection/types'
+import { ConnectionType } from '../../connection/types'
 import { SupportedLocale } from '../../constants/locales'
 import { DEFAULT_DEADLINE_FROM_NOW } from '../../constants/misc'
 import { RouterPreference } from '../../state/routing/types'
 import { SerializedPair, SerializedToken, SlippageTolerance } from './types'
 
-const selectedWallet = toConnectionType(localStorage.getItem(selectedWalletKey) ?? undefined)
+const selectedWallet = getPersistedConnectionMeta()?.type
 const currentTimestamp = () => new Date().getTime()
 
 export interface UserState {
@@ -79,7 +80,9 @@ const userSlice = createSlice({
   initialState,
   reducers: {
     updateSelectedWallet(state, { payload: { wallet } }) {
-      localStorage.setItem(selectedWalletKey, wallet)
+      if (!wallet) {
+        deletePersistedConnectionMeta()
+      }
       state.selectedWallet = wallet
     },
     updateUserLocale(state, action) {