wevm · tmm · Feb 20, 2022 · Feb 20, 2022 · Feb 20, 2022
diff --git a/jest.config.js b/jest.config.js
@@ -23,6 +23,7 @@ module.exports = {
     {
       ...config,
       displayName: 'core',
+      setupFilesAfterEnv: ['<rootDir>/packages/core/test/setup.ts'],
       testEnvironment: 'node',
       testRegex: 'packages/core/.*\\.test\\.ts$',
     },

diff --git a/packages/core/package.json b/packages/core/package.json
@@ -54,6 +54,7 @@
   "devDependencies": {
     "@walletconnect/ethereum-provider": "1.7.1",
     "ethers": "^5.5.1",
+    "wagmi-testing": "0.1.11",
     "walletlink": "^2.2.8"
   }
 }
diff --git a/packages/core/src/actions/accounts/balance.test.ts b/packages/core/src/actions/accounts/balance.test.ts
@@ -0,0 +1,62 @@
+import { contracts, wallets } from 'wagmi-testing'
+
+import { getProvider } from '../../../test'
+import { balanceAction } from './balance'
+
+const provider = getProvider()
+
+describe('balanceAction', () => {
+  it('fetches eth balance', async () => {
+    const balance = await balanceAction({
+      config: {
+        addressOrName: wallets.ethers1.address,
+      },
+      provider,
+    })
+    expect(balance).toMatchInlineSnapshot(`
+      {
+        "decimals": 18,
+        "formatted": "0.193861344139087225",
+        "symbol": "ETH",
+        "unit": "ether",
+        "value": {
+          "hex": "0x02b0bbdd89170d79",
+          "type": "BigNumber",
+        },
+      }
+    `)
+  })
+
+  it.skip('fetches token balance', async () => {
+    const balance = await balanceAction({
+      config: {
+        addressOrName: wallets.ethers3.address,
+        token: contracts.uniToken,
+      },
+      provider,
+    })
+    expect(balance).toMatchInlineSnapshot()
+  })
+
+  it('formats balance', async () => {
+    const balance = await balanceAction({
+      config: {
+        addressOrName: wallets.ethers1.address,
+        formatUnits: 'gwei',
+      },
+      provider,
+    })
+    expect(balance).toMatchInlineSnapshot(`
+      {
+        "decimals": 18,
+        "formatted": "193861344.139087225",
+        "symbol": "ETH",
+        "unit": "gwei",
+        "value": {
+          "hex": "0x02b0bbdd89170d79",
+          "type": "BigNumber",
+        },
+      }
+    `)
+  })
+})
diff --git a/packages/core/src/actions/accounts/balance.ts b/packages/core/src/actions/accounts/balance.ts
@@ -0,0 +1,54 @@
+import { ethers, utils } from 'ethers'
+
+import { defaultChains, defaultL2Chains, erc20ABI } from '../../constants'
+import { Balance, Chain, Unit, WithProvider } from '../../types'
+
+export type BalanceActionArgs = WithProvider<{
+  /** Chains to use for looking up native currency */
+  chains?: Chain[]
+  /** Configuration to use for balance */
+  config: {
+    /** Address or ENS name */
+    addressOrName: string
+    /** Units for formatting output */
+    formatUnits?: Unit | number
+    /** ERC-20 address */
+    token?: string
+  }
+}>
+
+export type BalanceActionResult = Balance
+
+export const balanceAction = async ({
+  chains = [...defaultChains, ...defaultL2Chains],
+  config,
+  provider,
+}: BalanceActionArgs): Promise<BalanceActionResult> => {
+  const unit = config.formatUnits ?? 'ether'
+
+  if (config.token) {
+    const contract = new ethers.Contract(config.token, erc20ABI, provider)
+    const [value, decimals, symbol] = await Promise.all([
+      contract.balanceOf(config.addressOrName),
+      contract.decimals(),
+      contract.symbol(),
+    ])
+    return {
+      decimals,
+      formatted: utils.formatUnits(value, unit),
+      symbol,
+      unit,
+      value,
+    }
+  }
+
+  const value = await provider.getBalance(config.addressOrName)
+  const chain = chains.find((x) => x.id === provider.network.chainId)
+  return {
+    decimals: chain?.nativeCurrency?.decimals ?? 18,
+    formatted: utils.formatUnits(value, unit),
+    symbol: chain?.nativeCurrency?.symbol ?? 'ETH',
+    unit,
+    value,
+  }
+}
diff --git a/packages/core/src/actions/accounts/index.ts b/packages/core/src/actions/accounts/index.ts
@@ -0,0 +1,2 @@
+export type { BalanceActionArgs, BalanceActionResult } from './balance'
+export { balanceAction } from './balance'
diff --git a/packages/core/src/actions/index.ts b/packages/core/src/actions/index.ts
@@ -0,0 +1,2 @@
+export type { BalanceActionArgs, BalanceActionResult } from './accounts'
+export { balanceAction } from './accounts'
diff --git a/packages/core/src/constants/units.ts b/packages/core/src/constants/units.ts
@@ -1,2 +1,10 @@
 // https://github.com/ethers-io/ethers.js/blob/master/packages/units/src.ts/index.ts#L10-L18
-export const units = ['wei', 'kwei', 'mwei', 'gwei', 'szabo', 'finney', 'ether']
+export const units = [
+  'wei',
+  'kwei',
+  'mwei',
+  'gwei',
+  'szabo',
+  'finney',
+  'ether',
+] as const
diff --git a/packages/core/src/index.test.ts b/packages/core/src/index.test.ts
@@ -5,6 +5,7 @@ it('should expose correct exports', () => {
     [
       "Connector",
       "InjectedConnector",
+      "balanceAction",
       "erc1155ABI",
       "erc20ABI",
       "erc721ABI",

diff --git a/packages/core/src/index.ts b/packages/core/src/index.ts
@@ -1,6 +1,9 @@
 export { Connector, InjectedConnector } from './connectors'
 export type { ConnectorData, ConnectorEvents } from './connectors'
 
+export type { BalanceActionArgs, BalanceActionResult } from './actions'
+export { balanceAction } from './actions'
+
 export {
   erc1155ABI,
   erc20ABI,
@@ -22,6 +25,6 @@ export {
   UserRejectedRequestError,
 } from './errors'
 
-export type { Chain, Unit } from './types'
+export type { Balance, Chain, Unit } from './types'
 
 export { normalizeChainId } from './utils'
diff --git a/packages/core/src/types/actions.ts b/packages/core/src/types/actions.ts
@@ -0,0 +1,6 @@
+import { BaseProvider } from '@ethersproject/providers'
+
+export type WithProvider<T> = T & {
+  /** Interface for connecting to network */
+  provider: BaseProvider
+}
diff --git a/packages/core/src/types/index.ts b/packages/core/src/types/index.ts
@@ -1,6 +1,18 @@
+import { BigNumber } from 'ethers'
+
 import { units } from '../constants'
 import './declarations'
 
+export type { WithProvider } from './actions'
+
+export type Balance = {
+  decimals: number
+  formatted: string
+  symbol: string
+  unit: Unit | number
+  value: BigNumber
+}
+
 export type Chain = {
   id: number
   name: AddEthereumChainParameter['chainName']

diff --git a/packages/core/test/index.ts b/packages/core/test/index.ts
@@ -0,0 +1,5 @@
+import { providers } from 'ethers'
+import { infuraApiKey } from 'wagmi-testing'
+
+export const getProvider = ({ chainId }: { chainId?: number } = {}) =>
+  new providers.InfuraProvider(chainId ?? 1, infuraApiKey)
diff --git a/packages/core/test/setup.ts b/packages/core/test/setup.ts
@@ -0,0 +1,11 @@
+import '@testing-library/jest-dom'
+
+import { server } from 'wagmi-testing'
+
+// Establish API mocking before all tests.
+beforeAll(() => server.listen())
+// Reset any request handlers that we may add during the tests,
+// so they don't affect other tests.
+afterEach(() => server.resetHandlers())
+// Clean up after the tests are finished.
+afterAll(() => server.close())
diff --git a/packages/react/src/hooks/accounts/useBalance.test.ts b/packages/react/src/hooks/accounts/useBalance.test.ts
@@ -75,6 +75,7 @@ describe('useBalance', () => {
               "decimals": 18,
               "formatted": "0.193861344139087225",
               "symbol": "ETH",
+              "unit": "ether",
               "value": {
                 "hex": "0x02b0bbdd89170d79",
                 "type": "BigNumber",
@@ -104,6 +105,7 @@ describe('useBalance', () => {
               "decimals": 18,
               "formatted": "0.193861344139087225",
               "symbol": "ETH",
+              "unit": "ether",
               "value": {
                 "hex": "0x02b0bbdd89170d79",
                 "type": "BigNumber",

diff --git a/packages/react/src/hooks/accounts/useBalance.ts b/packages/react/src/hooks/accounts/useBalance.ts
@@ -1,24 +1,23 @@
 import * as React from 'react'
-import { BigNumber, ethers, utils } from 'ethers'
-import { Unit, defaultChains, defaultL2Chains, erc20ABI } from 'wagmi-core'
+import { BigNumber } from 'ethers'
+import {
+  BalanceActionArgs,
+  balanceAction,
+  defaultChains,
+  defaultL2Chains,
+} from 'wagmi-core'
 
 import { useContext } from '../../context'
 import { useProvider } from '../providers'
 import { useBlockNumber } from '../network-status'
 import { useCacheBuster, useCancel } from '../utils'
 
 export type Config = {
-  /** Address or ENS name */
-  addressOrName?: string
-  /** Units for formatting output */
-  formatUnits?: Unit | number
   /** Disables fetching */
   skip?: boolean
-  /** ERC-20 address */
-  token?: string
   /** Subscribe to changes */
   watch?: boolean
-}
+} & Partial<BalanceActionArgs['config']>
 
 type State = {
   balance?: {
@@ -70,52 +69,22 @@ export const useBalance = ({
         }
         if (!config_.addressOrName) throw new Error('address is required')
 
-        const formatUnits_ = config_.formatUnits ?? 'ether'
-
         setState((x) => ({ ...x, error: undefined, loading: true }))
-        let balance: State['balance']
-        if (config_.token) {
-          const contract = new ethers.Contract(
-            config_.token,
-            erc20ABI,
-            provider,
-          )
-          const [value, decimals, symbol] = await Promise.all([
-            contract.balanceOf(config_.addressOrName),
-            contract.decimals(),
-            contract.symbol(),
-          ])
-          balance = {
-            decimals,
-            formatted: utils.formatUnits(value, formatUnits_),
-            symbol,
-            value,
-          }
-        } else {
-          const value = await provider.getBalance(config_.addressOrName)
-          const chain = [
+        const balance = await balanceAction({
+          chains: [
             ...(connector?.chains ?? []),
             ...defaultChains,
             ...defaultL2Chains,
-          ].find((x) => x.id === provider.network.chainId)
-          balance = {
-            decimals: chain?.nativeCurrency?.decimals ?? 18,
-            formatted: utils.formatUnits(value, formatUnits_),
-            symbol: chain?.nativeCurrency?.symbol ?? 'ETH',
-            value,
-          }
-        }
-
-        if (!didCancel) {
-          setState((x) => ({ ...x, balance, loading: false }))
-        }
+          ],
+          config: <BalanceActionArgs['config']>config_,
+          provider,
+        })
+        if (!didCancel) setState((x) => ({ ...x, balance, loading: false }))
 
         return { data: balance, error: undefined }
       } catch (error_) {
         const error = <Error>error_
-        if (!didCancel) {
-          setState((x) => ({ ...x, error, loading: false }))
-        }
+        if (!didCancel) setState((x) => ({ ...x, error, loading: false }))
         return { data: undefined, error }
       }
     },

diff --git a/packages/react/test/index.tsx b/packages/react/test/index.tsx
@@ -11,6 +11,7 @@ import {
   infuraApiKey,
   wallets,
 } from 'wagmi-testing'
+import { chain } from 'wagmi-core'
 
 import { Provider, ProviderProps } from '../src'
 
@@ -23,7 +24,7 @@ type Props = ProviderProps & {
     | React.ReactNode
 }
 export const wrapper = (props: Props) => {
-  const network = props.chainId ?? 1
+  const network = props.chainId ?? chain.mainnet.id
   return (
     <Provider
       connectors={[

diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1,2 @@
		export type { BalanceActionArgs, BalanceActionResult } from './balance'
		export { balanceAction } from './balance'
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1,2 @@
		export type { BalanceActionArgs, BalanceActionResult } from './accounts'
		export { balanceAction } from './accounts'