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createMemoryClient

createMemoryClient<TCommon, TAccountOrAddress, TRpcSchema>(options?): object

Creates a MemoryClient which is a viem client with an in-memory Ethereum client as its transport. It comes batteries included with all wallet, test, public, and tevm actions.

Type Parameters

• TCommon extends object & object & ChainConfig<undefined | ChainFormatters, undefined | Record<string, unknown>> = object & object & ChainConfig<undefined | ChainFormatters, undefined | Record<string, unknown>>

• TAccountOrAddress extends undefined | `0x${string}` | Account = undefined

• TRpcSchema extends undefined | RpcSchema = [object, object, object, object, object]

Parameters

• options?: MemoryClientOptions<TCommon, TAccountOrAddress, TRpcSchema>

Returns

object

account

account: TAccountOrAddress extends Account ? Account : undefined

The Account of the Client.

addChain()

addChain: (args) => Promise<void>

Adds an EVM chain to the wallet.

Example

import { createWalletClient, custom } from 'viem'
import { optimism } from 'viem/chains'


const client = createWalletClient({
  transport: custom(window.ethereum),
})
await client.addChain({ chain: optimism })

Parameters

• args: AddChainParameters

AddChainParameters

Returns

Promise<void>

batch?

optional batch: object

Flags for batch settings.

batch.multicall?

optional batch.multicall: boolean | object

Toggle to enable eth_call multicall aggregation.

cacheTime

cacheTime: number

Time (in ms) that cached data will remain in memory.

call()

call: (parameters) => Promise<CallReturnType>

Parameters

• parameters: CallParameters<TCommon>

Returns

Promise<CallReturnType>

The call data. CallReturnType

ccipRead?

optional ccipRead: false | object

CCIP Read configuration.

chain

chain: TCommon

Chain for the client.

createBlockFilter()

createBlockFilter: () => Promise<object>

Returns

Promise<object>

Filter. CreateBlockFilterReturnType

id

id: `0x${string}`

request

request: EIP1193RequestFn<readonly [object, object, object]>

type

type: "block"

createContractEventFilter()

createContractEventFilter: <abi, eventName, args, strict, fromBlock, toBlock>(args) => Promise<CreateContractEventFilterReturnType<abi, eventName, args, strict, fromBlock, toBlock>>

Type Parameters

• abi extends Abi | readonly unknown[]

• eventName extends undefined | string

• args extends undefined | Record<string, unknown> | readonly unknown[]

• strict extends undefined | boolean = undefined

• fromBlock extends undefined | bigint | BlockTag = undefined

• toBlock extends undefined | bigint | BlockTag = undefined

Parameters

• args: CreateContractEventFilterParameters<abi, eventName, args, strict, fromBlock, toBlock>

CreateContractEventFilterParameters

Returns

Promise<CreateContractEventFilterReturnType<abi, eventName, args, strict, fromBlock, toBlock>>

Filter. CreateContractEventFilterReturnType

createEventFilter()

createEventFilter: <abiEvent, abiEvents, strict, fromBlock, toBlock, _EventName, _Args>(args?) => Promise<{ [K in string | number | symbol]: Filter<“event”, abiEvents, _EventName, _Args, strict, fromBlock, toBlock>[K] }>

Type Parameters

• abiEvent extends undefined | AbiEvent = undefined

• abiEvents extends undefined | readonly unknown[] | readonly AbiEvent[] = abiEvent extends AbiEvent ? [abiEvent<abiEvent>] : undefined

• strict extends undefined | boolean = undefined

• fromBlock extends undefined | bigint | BlockTag = undefined

• toBlock extends undefined | bigint | BlockTag = undefined

• _EventName extends undefined | string = MaybeAbiEventName<abiEvent>

• _Args extends undefined | Record<string, unknown> | readonly unknown[] = undefined

Parameters

• args?: CreateEventFilterParameters<abiEvent, abiEvents, strict, fromBlock, toBlock, _EventName, _Args>

CreateEventFilterParameters

Returns

Promise<{ [K in string | number | symbol]: Filter<“event”, abiEvents, _EventName, _Args, strict, fromBlock, toBlock>[K] }>

Filter. CreateEventFilterReturnType

createPendingTransactionFilter()

createPendingTransactionFilter: () => Promise<object>

Returns

Promise<object>

Filter. CreateBlockFilterReturnType

id

id: `0x${string}`

request

request: EIP1193RequestFn<readonly [object, object, object]>

type

type: "transaction"

deployContract()

deployContract: <abi, chainOverride>(args) => Promise<`0x${string}`>

Type Parameters

• abi extends Abi | readonly unknown[]

• chainOverride extends undefined | Chain

Parameters

• args: DeployContractParameters<abi, TCommon, TAccountOrAddress extends Account ? Account : undefined, chainOverride>

DeployContractParameters

Returns

Promise<`0x${string}`>

The Transaction hash. DeployContractReturnType

dropTransaction()

dropTransaction: (args) => Promise<void>

Removes a transaction from the mempool.

Example

import { createTestClient, http } from 'viem'
import { foundry } from 'viem/chains'


const client = createTestClient({
  mode: 'anvil',
  chain: 'foundry',
  transport: http(),
})
await client.dropTransaction({
  hash: '0xe58dceb6b20b03965bb678e27d141e151d7d4efc2334c2d6a49b9fac523f7364'
})

Parameters

• args: DropTransactionParameters

DropTransactionParameters

Returns

Promise<void>

dumpState()

dumpState: () => Promise<`0x${string}`>

Serializes the current state (including contracts code, contract’s storage, accounts properties, etc.) into a savable data blob.

Example

import { createTestClient, http } from 'viem'
import { foundry } from 'viem/chains'


const client = createTestClient({
  mode: 'anvil',
  chain: 'foundry',
  transport: http(),
})
await client.dumpState()

Returns

Promise<`0x${string}`>

estimateContractGas()

estimateContractGas: <chain, abi, functionName, args>(args) => Promise<bigint>

Type Parameters

• chain extends undefined | Chain

• abi extends Abi | readonly unknown[]

• functionName extends string

• args extends unknown

Parameters

• args: EstimateContractGasParameters<abi, functionName, args, chain>

EstimateContractGasParameters

Returns

Promise<bigint>

The gas estimate (in wei). EstimateContractGasReturnType

estimateFeesPerGas()

estimateFeesPerGas: <chainOverride, type>(args?) => Promise<EstimateFeesPerGasReturnType<type>>

Type Parameters

• chainOverride extends undefined | Chain = undefined

• type extends FeeValuesType = "eip1559"

Parameters

• args?: EstimateFeesPerGasParameters<TCommon, chainOverride, type>

Returns

Promise<EstimateFeesPerGasReturnType<type>>

An estimate (in wei) for the fees per gas. EstimateFeesPerGasReturnType

estimateGas()

estimateGas: (args) => Promise<bigint>

Parameters

• args: EstimateGasParameters<TCommon>

EstimateGasParameters

Returns

Promise<bigint>

The gas estimate (in wei). EstimateGasReturnType

estimateMaxPriorityFeePerGas()

estimateMaxPriorityFeePerGas: <chainOverride>(args?) => Promise<bigint>

Type Parameters

• chainOverride extends undefined | Chain = undefined

Parameters

• args?: GetChainParameter<TCommon, chainOverride>

Returns

Promise<bigint>

An estimate (in wei) for the max priority fee per gas. EstimateMaxPriorityFeePerGasReturnType

extend()

extend: <client>(fn) => Client<TevmTransport, TCommon, TAccountOrAddress extends Account ? Account : undefined, [object, object, object, object, object], { [K in string | number | symbol]: client[K] } & TevmActions & PublicActions<TevmTransport, TCommon, TAccountOrAddress extends Account ? Account : undefined> & WalletActions<TCommon, TAccountOrAddress extends Account ? Account : undefined> & TestActions>

Type Parameters

• client extends object & ExactPartial<ExtendableProtectedActions<TevmTransport, TCommon, TAccountOrAddress extends Account ? Account : undefined>>

Parameters

• fn

Returns

Client<TevmTransport, TCommon, TAccountOrAddress extends Account ? Account : undefined, [object, object, object, object, object], { [K in string | number | symbol]: client[K] } & TevmActions & PublicActions<TevmTransport, TCommon, TAccountOrAddress extends Account ? Account : undefined> & WalletActions<TCommon, TAccountOrAddress extends Account ? Account : undefined> & TestActions>

getAddresses()

getAddresses: () => Promise<GetAddressesReturnType>

Returns

Promise<GetAddressesReturnType>

List of account addresses owned by the wallet or client. GetAddressesReturnType

getAutomine()

getAutomine: () => Promise<boolean>

Returns

Promise<boolean>

Whether or not the node is auto mining. GetAutomineReturnType

getBalance()

getBalance: (args) => Promise<bigint>

Parameters

• args: GetBalanceParameters

GetBalanceParameters

Returns

Promise<bigint>

The balance of the address in wei. GetBalanceReturnType

getBlobBaseFee()

getBlobBaseFee: () => Promise<bigint>

Returns

Promise<bigint>

The blob base fee (in wei). GetBlobBaseFeeReturnType

getBlock()

getBlock: <includeTransactions, blockTag>(args?) => Promise<{ [K in string | number | symbol]: FormattedBlock<TCommon, includeTransactions, blockTag>[K] }>

Type Parameters

• includeTransactions extends boolean = false

• blockTag extends BlockTag = "latest"

Parameters

• args?: GetBlockParameters<includeTransactions, blockTag>

GetBlockParameters

Returns

Promise<{ [K in string | number | symbol]: FormattedBlock<TCommon, includeTransactions, blockTag>[K] }>

Information about the block. GetBlockReturnType

getBlockNumber()

getBlockNumber: (args?) => Promise<bigint>

Parameters

• args?: GetBlockNumberParameters

GetBlockNumberParameters

Returns

Promise<bigint>

The number of the block. GetBlockNumberReturnType

getBlockTransactionCount()

getBlockTransactionCount: (args?) => Promise<number>

Parameters

• args?: GetBlockTransactionCountParameters

GetBlockTransactionCountParameters

Returns

Promise<number>

The block transaction count. GetBlockTransactionCountReturnType

getBytecode()

getBytecode: (args) => Promise<GetCodeReturnType>

Parameters

• args: GetCodeParameters

Returns

Promise<GetCodeReturnType>

getChainId

getChainId: () => Promise<number> & () => Promise<number>

Returns the chain ID associated with the current network.

Example

import { createPublicClient, http } from 'viem'
import { mainnet } from 'viem/chains'


const client = createPublicClient({
  chain: mainnet,
  transport: http(),
})
const chainId = await client.getChainId()
// 1

getCode()

getCode: (args) => Promise<GetCodeReturnType>

Parameters

• args: GetCodeParameters

GetBytecodeParameters

Returns

Promise<GetCodeReturnType>

The contract’s bytecode. GetBytecodeReturnType

getContractEvents()

getContractEvents: <abi, eventName, strict, fromBlock, toBlock>(args) => Promise<GetContractEventsReturnType<abi, eventName, strict, fromBlock, toBlock>>

Type Parameters

• abi extends Abi | readonly unknown[]

• eventName extends undefined | string = undefined

• strict extends undefined | boolean = undefined

• fromBlock extends undefined | bigint | BlockTag = undefined

• toBlock extends undefined | bigint | BlockTag = undefined

Parameters

• args: GetContractEventsParameters<abi, eventName, strict, fromBlock, toBlock>

Returns

Promise<GetContractEventsReturnType<abi, eventName, strict, fromBlock, toBlock>>

A list of event logs. GetContractEventsReturnType

getEip712Domain()

getEip712Domain: (args) => Promise<GetEip712DomainReturnType>

Parameters

• args: GetEip712DomainParameters

Returns

Promise<GetEip712DomainReturnType>

The EIP-712 domain, fields, and extensions. GetEip712DomainReturnType

getEnsAddress()

getEnsAddress: (args) => Promise<GetEnsAddressReturnType>

Parameters

• args

GetEnsAddressParameters

• args.blockNumber?: bigint

The balance of the account at a block number.

• args.blockTag?: BlockTag

The balance of the account at a block tag.

Default

'latest'

• args.coinType?: number

ENSIP-9 compliant coinType used to resolve addresses for other chains

• args.gatewayUrls?: string[]

Universal Resolver gateway URLs to use for resolving CCIP-read requests.

• args.name: string

Name to get the address for.

• args.strict?: boolean

Whether or not to throw errors propagated from the ENS Universal Resolver Contract.

• args.universalResolverAddress?: `0x${string}`

Address of ENS Universal Resolver Contract.

Returns

Promise<GetEnsAddressReturnType>

Address for ENS name or null if not found. GetEnsAddressReturnType

getEnsAvatar()

getEnsAvatar: (args) => Promise<GetEnsAvatarReturnType>

Parameters

• args

GetEnsAvatarParameters

• args.assetGatewayUrls?: AssetGatewayUrls

Gateway urls to resolve IPFS and/or Arweave assets.

• args.blockNumber?: bigint

The balance of the account at a block number.

• args.blockTag?: BlockTag

The balance of the account at a block tag.

Default

'latest'

• args.gatewayUrls?: string[]

Universal Resolver gateway URLs to use for resolving CCIP-read requests.

• args.name: string

ENS name to get Text for.

• args.strict?: boolean

Whether or not to throw errors propagated from the ENS Universal Resolver Contract.

• args.universalResolverAddress?: `0x${string}`

Address of ENS Universal Resolver Contract.

Returns

Promise<GetEnsAvatarReturnType>

Avatar URI or null if not found. GetEnsAvatarReturnType

getEnsName()

getEnsName: (args) => Promise<GetEnsNameReturnType>

Parameters

• args

GetEnsNameParameters

• args.address: `0x${string}`

Address to get ENS name for.

• args.blockNumber?: bigint

The balance of the account at a block number.

• args.blockTag?: BlockTag

The balance of the account at a block tag.

Default

'latest'

• args.gatewayUrls?: string[]

Universal Resolver gateway URLs to use for resolving CCIP-read requests.

• args.strict?: boolean

Whether or not to throw errors propagated from the ENS Universal Resolver Contract.

• args.universalResolverAddress?: `0x${string}`

Address of ENS Universal Resolver Contract.

Returns

Promise<GetEnsNameReturnType>

Name or null if not found. GetEnsNameReturnType

getEnsResolver()

getEnsResolver: (args) => Promise<`0x${string}`>

Parameters

• args

GetEnsResolverParameters

• args.blockNumber?: bigint

The balance of the account at a block number.

• args.blockTag?: BlockTag

The balance of the account at a block tag.

Default

'latest'

• args.name: string

Name to get the address for.

• args.universalResolverAddress?: `0x${string}`

Address of ENS Universal Resolver Contract.

Returns

Promise<`0x${string}`>

Address for ENS resolver. GetEnsResolverReturnType

getEnsText()

getEnsText: (args) => Promise<GetEnsTextReturnType>

Parameters

• args

GetEnsTextParameters

• args.blockNumber?: bigint

The balance of the account at a block number.

• args.blockTag?: BlockTag

The balance of the account at a block tag.

Default

'latest'

• args.gatewayUrls?: string[]

Universal Resolver gateway URLs to use for resolving CCIP-read requests.

• args.key: string

Text record to retrieve.

• args.name: string

ENS name to get Text for.

• args.strict?: boolean

Whether or not to throw errors propagated from the ENS Universal Resolver Contract.

• args.universalResolverAddress?: `0x${string}`

Address of ENS Universal Resolver Contract.

Returns

Promise<GetEnsTextReturnType>

Address for ENS resolver. GetEnsTextReturnType

getFeeHistory()

getFeeHistory: (args) => Promise<GetFeeHistoryReturnType>

Parameters

• args: GetFeeHistoryParameters

GetFeeHistoryParameters

Returns

Promise<GetFeeHistoryReturnType>

The gas estimate (in wei). GetFeeHistoryReturnType

getFilterChanges()

getFilterChanges: <filterType, abi, eventName, strict, fromBlock, toBlock>(args) => Promise<GetFilterChangesReturnType<filterType, abi, eventName, strict, fromBlock, toBlock>>

Type Parameters

• filterType extends FilterType

• abi extends undefined | Abi | readonly unknown[]

• eventName extends undefined | string

• strict extends undefined | boolean = undefined

• fromBlock extends undefined | bigint | BlockTag = undefined

• toBlock extends undefined | bigint | BlockTag = undefined

Parameters

• args: GetFilterChangesParameters<filterType, abi, eventName, strict, fromBlock, toBlock>

GetFilterChangesParameters

Returns

Promise<GetFilterChangesReturnType<filterType, abi, eventName, strict, fromBlock, toBlock>>

Logs or hashes. GetFilterChangesReturnType

getFilterLogs()

getFilterLogs: <abi, eventName, strict, fromBlock, toBlock>(args) => Promise<GetFilterLogsReturnType<abi, eventName, strict, fromBlock, toBlock>>

Type Parameters

• abi extends undefined | Abi | readonly unknown[]

• eventName extends undefined | string

• strict extends undefined | boolean = undefined

• fromBlock extends undefined | bigint | BlockTag = undefined

• toBlock extends undefined | bigint | BlockTag = undefined

Parameters

• args: GetFilterLogsParameters<abi, eventName, strict, fromBlock, toBlock>

GetFilterLogsParameters

Returns

Promise<GetFilterLogsReturnType<abi, eventName, strict, fromBlock, toBlock>>

A list of event logs. GetFilterLogsReturnType

getGasPrice()

getGasPrice: () => Promise<bigint>

Returns

Promise<bigint>

The gas price (in wei). GetGasPriceReturnType

getLogs()

getLogs: <abiEvent, abiEvents, strict, fromBlock, toBlock>(args?) => Promise<GetLogsReturnType<abiEvent, abiEvents, strict, fromBlock, toBlock>>

Type Parameters

• abiEvent extends undefined | AbiEvent = undefined

• abiEvents extends undefined | readonly unknown[] | readonly AbiEvent[] = abiEvent extends AbiEvent ? [abiEvent<abiEvent>] : undefined

• strict extends undefined | boolean = undefined

• fromBlock extends undefined | bigint | BlockTag = undefined

• toBlock extends undefined | bigint | BlockTag = undefined

Parameters

• args?: GetLogsParameters<abiEvent, abiEvents, strict, fromBlock, toBlock>

GetLogsParameters

Returns

Promise<GetLogsReturnType<abiEvent, abiEvents, strict, fromBlock, toBlock>>

A list of event logs. GetLogsReturnType

getPermissions()

getPermissions: () => Promise<GetPermissionsReturnType>

Returns

Promise<GetPermissionsReturnType>

The wallet permissions. GetPermissionsReturnType

getProof()

getProof: (args) => Promise<GetProofReturnType>

Parameters

• args: GetProofParameters

Returns

Promise<GetProofReturnType>

Proof data. GetProofReturnType

getStorageAt()

getStorageAt: (args) => Promise<GetStorageAtReturnType>

Parameters

• args: GetStorageAtParameters

GetStorageAtParameters

Returns

Promise<GetStorageAtReturnType>

The value of the storage slot. GetStorageAtReturnType

getTransaction()

getTransaction: <blockTag>(args) => Promise<{ [K in string | number | symbol]: FormattedTransaction<TCommon, blockTag>[K] }>

Type Parameters

• blockTag extends BlockTag = "latest"

Parameters

• args: GetTransactionParameters<blockTag>

GetTransactionParameters

Returns

Promise<{ [K in string | number | symbol]: FormattedTransaction<TCommon, blockTag>[K] }>

The transaction information. GetTransactionReturnType

getTransactionConfirmations()

getTransactionConfirmations: (args) => Promise<bigint>

Parameters

• args: GetTransactionConfirmationsParameters<TCommon>

GetTransactionConfirmationsParameters

Returns

Promise<bigint>

The number of blocks passed since the transaction was processed. If confirmations is 0, then the Transaction has not been confirmed & processed yet. GetTransactionConfirmationsReturnType

getTransactionCount()

getTransactionCount: (args) => Promise<number>

Parameters

• args: GetTransactionCountParameters

GetTransactionCountParameters

Returns

Promise<number>

The number of transactions an account has sent. GetTransactionCountReturnType

getTransactionReceipt()

getTransactionReceipt: (args) => Promise<ExtractChainFormatterReturnType<TCommon, "transactionReceipt", TransactionReceipt>>

Parameters

• args: GetTransactionReceiptParameters

GetTransactionReceiptParameters

Returns

Promise<ExtractChainFormatterReturnType<TCommon, "transactionReceipt", TransactionReceipt>>

The transaction receipt. GetTransactionReceiptReturnType

getTxpoolContent()

getTxpoolContent: () => Promise<GetTxpoolContentReturnType>

Returns

Promise<GetTxpoolContentReturnType>

Transaction pool content. GetTxpoolContentReturnType

getTxpoolStatus()

getTxpoolStatus: () => Promise<GetTxpoolStatusReturnType>

Returns

Promise<GetTxpoolStatusReturnType>

Transaction pool status. GetTxpoolStatusReturnType

impersonateAccount()

impersonateAccount: (args) => Promise<void>

Impersonate an account or contract address. This lets you send transactions from that account even if you don’t have access to its private key.

Example

import { createTestClient, http } from 'viem'
import { foundry } from 'viem/chains'


const client = createTestClient({
  mode: 'anvil',
  chain: 'foundry',
  transport: http(),
})
await client.impersonateAccount({
  address: '0xA0Cf798816D4b9b9866b5330EEa46a18382f251e',
})

Parameters

• args: ImpersonateAccountParameters

ImpersonateAccountParameters

Returns

Promise<void>

increaseTime()

increaseTime: (args) => Promise<`0x${string}`>

Jump forward in time by the given amount of time, in seconds.

Example

import { createTestClient, http } from 'viem'
import { foundry } from 'viem/chains'


const client = createTestClient({
  mode: 'anvil',
  chain: 'foundry',
  transport: http(),
})
await client.increaseTime({
  seconds: 420,
})

Parameters

• args: IncreaseTimeParameters

– IncreaseTimeParameters

Returns

Promise<`0x${string}`>

inspectTxpool()

inspectTxpool: () => Promise<InspectTxpoolReturnType>

Returns

Promise<InspectTxpoolReturnType>

Transaction pool inspection data. InspectTxpoolReturnType

key

key: string

A key for the client.

loadState()

loadState: (args) => Promise<void>

Adds state previously dumped with dumpState to the current chain.

Example

import { createTestClient, http } from 'viem'
import { foundry } from 'viem/chains'


const client = createTestClient({
  mode: 'anvil',
  chain: 'foundry',
  transport: http(),
})
await client.loadState({ state: '0x...' })

Parameters

• args: LoadStateParameters

Returns

Promise<void>

mine()

mine: (args) => Promise<void>

Mine a specified number of blocks.

Example

import { createTestClient, http } from 'viem'
import { foundry } from 'viem/chains'


const client = createTestClient({
  mode: 'anvil',
  chain: 'foundry',
  transport: http(),
})
await client.mine({ blocks: 1 })

Parameters

• args: MineParameters

– MineParameters

Returns

Promise<void>

multicall()

multicall: <contracts, allowFailure>(args) => Promise<MulticallReturnType<contracts, allowFailure>>

Type Parameters

• contracts extends readonly unknown[]

• allowFailure extends boolean = true

Parameters

• args: MulticallParameters<contracts, allowFailure>

MulticallParameters

Returns

Promise<MulticallReturnType<contracts, allowFailure>>

An array of results with accompanying status. MulticallReturnType

name

name: string

A name for the client.

pollingInterval

pollingInterval: number

Frequency (in ms) for polling enabled actions & events. Defaults to 4_000 milliseconds.

prepareTransactionRequest

prepareTransactionRequest: <request, chainOverride, accountOverride>(args) => Promise<{ [K in string | number | symbol]: (UnionRequiredBy<Extract<(…) & (…) & (…), (…) extends (…) ? (…) : (…)> & Object, ParameterTypeToParameters<(…)[(…)] extends readonly (…)[] ? (…)[(…)] : (…) | (…) | (…) | (…) | (…) | (…)>> & (unknown extends request[“kzg”] ? Object : Pick<request, “kzg”>))[K] }> & <request, chainOverride, accountOverride>(args) => Promise<{ [K in string | number | symbol]: (UnionRequiredBy<Extract<(…) & (…) & (…), (…) extends (…) ? (…) : (…)> & Object, ParameterTypeToParameters<(…)[(…)] extends readonly (…)[] ? (…)[(…)] : (…) | (…) | (…) | (…) | (…) | (…)>> & (unknown extends request[“kzg”] ? Object : Pick<request, “kzg”>))[K] }>

Prepares a transaction request for signing.

Param

PrepareTransactionRequestParameters

Examples

import { createWalletClient, custom } from 'viem'
import { mainnet } from 'viem/chains'


const client = createWalletClient({
  chain: mainnet,
  transport: custom(window.ethereum),
})
const request = await client.prepareTransactionRequest({
  account: '0xA0Cf798816D4b9b9866b5330EEa46a18382f251e',
  to: '0x0000000000000000000000000000000000000000',
  value: 1n,
})
// Account Hoisting
import { createWalletClient, http } from 'viem'
import { privateKeyToAccount } from 'viem/accounts'
import { mainnet } from 'viem/chains'


const client = createWalletClient({
  account: privateKeyToAccount('0x…'),
  chain: mainnet,
  transport: custom(window.ethereum),
})
const request = await client.prepareTransactionRequest({
  to: '0x0000000000000000000000000000000000000000',
  value: 1n,
})

readContract()

readContract: <abi, functionName, args>(args) => Promise<ReadContractReturnType<abi, functionName, args>>

Type Parameters

• abi extends Abi | readonly unknown[]

• functionName extends string

• args extends unknown

Parameters

• args: ReadContractParameters<abi, functionName, args>

ReadContractParameters

Returns

Promise<ReadContractReturnType<abi, functionName, args>>

The response from the contract. Type is inferred. ReadContractReturnType

removeBlockTimestampInterval()

removeBlockTimestampInterval: () => Promise<void>

Removes setBlockTimestampInterval if it exists.

Example

import { createTestClient, http } from 'viem'
import { foundry } from 'viem/chains'
import { removeBlockTimestampInterval } from 'viem/test'


const client = createTestClient({
  mode: 'anvil',
  chain: 'foundry',
  transport: http(),
})
await client.removeBlockTimestampInterval()

Returns

Promise<void>

request

request: EIP1193RequestFn<[object, object, object, object, object]>

Request function wrapped with friendly error handling

requestAddresses()

requestAddresses: () => Promise<RequestAddressesReturnType>

Returns

Promise<RequestAddressesReturnType>

List of accounts managed by a wallet RequestAddressesReturnType

requestPermissions()

requestPermissions: (args) => Promise<RequestPermissionsReturnType>

Parameters

• args

RequestPermissionsParameters

• args.eth_accounts: Record<string, any>

Returns

Promise<RequestPermissionsReturnType>

The wallet permissions. RequestPermissionsReturnType

reset()

reset: (args?) => Promise<void>

Resets fork back to its original state.

Example

import { createTestClient, http } from 'viem'
import { foundry } from 'viem/chains'


const client = createTestClient({
  mode: 'anvil',
  chain: 'foundry',
  transport: http(),
})
await client.reset({ blockNumber: 69420n })

Parameters

• args?: ResetParameters

– ResetParameters

Returns

Promise<void>

revert()

revert: (args) => Promise<void>

Revert the state of the blockchain at the current block.

Example

import { createTestClient, http } from 'viem'
import { foundry } from 'viem/chains'


const client = createTestClient({
  mode: 'anvil',
  chain: 'foundry',
  transport: http(),
})
await client.revert({ id: '0x…' })

Parameters

• args: RevertParameters

– RevertParameters

Returns

Promise<void>

sendRawTransaction

sendRawTransaction: (args) => Promise<`0x${string}`> & (args) => Promise<`0x${string}`>

Sends a signed transaction to the network

Param

Client to use

Param

SendRawTransactionParameters

Example

import { createWalletClient, custom } from 'viem'
import { mainnet } from 'viem/chains'
import { sendRawTransaction } from 'viem/wallet'


const client = createWalletClient({
  chain: mainnet,
  transport: custom(window.ethereum),
})


const hash = await client.sendRawTransaction({
  serializedTransaction: '0x02f850018203118080825208808080c080a04012522854168b27e5dc3d5839bab5e6b39e1a0ffd343901ce1622e3d64b48f1a04e00902ae0502c4728cbf12156290df99c3ed7de85b1dbfe20b5c36931733a33'
})

sendTransaction()

sendTransaction: <request, chainOverride>(args) => Promise<`0x${string}`>

Type Parameters

• request extends Omit<object, "from"> | Omit<object, "from"> | Omit<object, "from"> | Omit<object, "from"> | Omit<object, "from"> & object

• chainOverride extends undefined | Chain = undefined

Parameters

• args: SendTransactionParameters<TCommon, TAccountOrAddress extends Account ? Account : undefined, chainOverride, request>

SendTransactionParameters

Returns

Promise<`0x${string}`>

The Transaction hash. SendTransactionReturnType

sendUnsignedTransaction()

sendUnsignedTransaction: <chain>(args) => Promise<`0x${string}`>

Type Parameters

• chain extends undefined | Chain

Parameters

• args: SendUnsignedTransactionParameters<chain>

– SendUnsignedTransactionParameters

Returns

Promise<`0x${string}`>

The transaction hash. SendUnsignedTransactionReturnType

setAutomine()

setAutomine: (args) => Promise<void>

Enables or disables the automatic mining of new blocks with each new transaction submitted to the network.

Example

import { createTestClient, http } from 'viem'
import { foundry } from 'viem/chains'


const client = createTestClient({
  mode: 'anvil',
  chain: 'foundry',
  transport: http(),
})
await client.setAutomine()

Parameters

• args: boolean

Returns

Promise<void>

setBalance()

setBalance: (args) => Promise<void>

Modifies the balance of an account.

Example

import { createTestClient, http, parseEther } from 'viem'
import { foundry } from 'viem/chains'


const client = createTestClient({
  mode: 'anvil',
  chain: 'foundry',
  transport: http(),
})
await client.setBalance({
  address: '0xa5cc3c03994DB5b0d9A5eEdD10CabaB0813678AC',
  value: parseEther('1'),
})

Parameters

• args: SetBalanceParameters

– SetBalanceParameters

Returns

Promise<void>

setBlockGasLimit()

setBlockGasLimit: (args) => Promise<void>

Sets the block’s gas limit.

Example

import { createTestClient, http } from 'viem'
import { foundry } from 'viem/chains'


const client = createTestClient({
  mode: 'anvil',
  chain: 'foundry',
  transport: http(),
})
await client.setBlockGasLimit({ gasLimit: 420_000n })

Parameters

• args: SetBlockGasLimitParameters

– SetBlockGasLimitParameters

Returns

Promise<void>

setBlockTimestampInterval()

setBlockTimestampInterval: (args) => Promise<void>

Similar to increaseTime, but sets a block timestamp interval. The timestamp of future blocks will be computed as lastBlock_timestamp + interval.

Example

import { createTestClient, http } from 'viem'
import { foundry } from 'viem/chains'


const client = createTestClient({
  mode: 'anvil',
  chain: 'foundry',
  transport: http(),
})
await client.setBlockTimestampInterval({ interval: 5 })

Parameters

• args: SetBlockTimestampIntervalParameters

– SetBlockTimestampIntervalParameters

Returns

Promise<void>

setCode()

setCode: (args) => Promise<void>

Modifies the bytecode stored at an account’s address.

Example

import { createTestClient, http } from 'viem'
import { foundry } from 'viem/chains'


const client = createTestClient({
  mode: 'anvil',
  chain: 'foundry',
  transport: http(),
})
await client.setCode({
  address: '0xe846c6fcf817734ca4527b28ccb4aea2b6663c79',
  bytecode: '0x60806040526000600355600019600955600c80546001600160a01b031916737a250d5630b4cf539739df…',
})

Parameters

• args: SetCodeParameters

– SetCodeParameters

Returns

Promise<void>

setCoinbase()

setCoinbase: (args) => Promise<void>

Sets the coinbase address to be used in new blocks.

Example

import { createTestClient, http } from 'viem'
import { foundry } from 'viem/chains'


const client = createTestClient({
  mode: 'anvil',
  chain: 'foundry',
  transport: http(),
})
await client.setCoinbase({
  address: '0xe846c6fcf817734ca4527b28ccb4aea2b6663c79',
})

Parameters

• args: SetCoinbaseParameters

– SetCoinbaseParameters

Returns

Promise<void>

setIntervalMining()

setIntervalMining: (args) => Promise<void>

Sets the automatic mining interval (in seconds) of blocks. Setting the interval to 0 will disable automatic mining.

Example

import { createTestClient, http } from 'viem'
import { foundry } from 'viem/chains'


const client = createTestClient({
  mode: 'anvil',
  chain: 'foundry',
  transport: http(),
})
await client.setIntervalMining({ interval: 5 })

Parameters

• args: SetIntervalMiningParameters

– SetIntervalMiningParameters

Returns

Promise<void>

setLoggingEnabled()

setLoggingEnabled: (args) => Promise<void>

Enable or disable logging on the test node network.

Example

import { createTestClient, http } from 'viem'
import { foundry } from 'viem/chains'


const client = createTestClient({
  mode: 'anvil',
  chain: 'foundry',
  transport: http(),
})
await client.setLoggingEnabled()

Parameters

• args: boolean

Returns

Promise<void>

setMinGasPrice()

setMinGasPrice: (args) => Promise<void>

Change the minimum gas price accepted by the network (in wei).

Note: setMinGasPrice can only be used on clients that do not have EIP-1559 enabled.

Example

import { createTestClient, http, parseGwei } from 'viem'
import { foundry } from 'viem/chains'


const client = createTestClient({
  mode: 'anvil',
  chain: 'foundry',
  transport: http(),
})
await client.setMinGasPrice({
  gasPrice: parseGwei('20'),
})

Parameters

• args: SetMinGasPriceParameters

– SetBlockGasLimitParameters

Returns

Promise<void>

setNextBlockBaseFeePerGas()

setNextBlockBaseFeePerGas: (args) => Promise<void>

Sets the next block’s base fee per gas.

Example

import { createTestClient, http, parseGwei } from 'viem'
import { foundry } from 'viem/chains'


const client = createTestClient({
  mode: 'anvil',
  chain: 'foundry',
  transport: http(),
})
await client.setNextBlockBaseFeePerGas({
  baseFeePerGas: parseGwei('20'),
})

Parameters

• args: SetNextBlockBaseFeePerGasParameters

– SetNextBlockBaseFeePerGasParameters

Returns

Promise<void>

setNextBlockTimestamp()

setNextBlockTimestamp: (args) => Promise<void>

Sets the next block’s timestamp.

Example

import { createTestClient, http } from 'viem'
import { foundry } from 'viem/chains'


const client = createTestClient({
  mode: 'anvil',
  chain: 'foundry',
  transport: http(),
})
await client.setNextBlockTimestamp({ timestamp: 1671744314n })

Parameters

• args: SetNextBlockTimestampParameters

– SetNextBlockTimestampParameters

Returns

Promise<void>

setNonce()

setNonce: (args) => Promise<void>

Modifies (overrides) the nonce of an account.

Example

import { createTestClient, http } from 'viem'
import { foundry } from 'viem/chains'


const client = createTestClient({
  mode: 'anvil',
  chain: 'foundry',
  transport: http(),
})
await client.setNonce({
  address: '0xa5cc3c03994DB5b0d9A5eEdD10CabaB0813678AC',
  nonce: 420,
})

Parameters

• args: SetNonceParameters

– SetNonceParameters

Returns

Promise<void>

setRpcUrl()

setRpcUrl: (args) => Promise<void>

Sets the backend RPC URL.

Example

import { createTestClient, http } from 'viem'
import { foundry } from 'viem/chains'


const client = createTestClient({
  mode: 'anvil',
  chain: 'foundry',
  transport: http(),
})
await client.setRpcUrl('https://eth-mainnet.g.alchemy.com/v2')

Parameters

• args: string

Returns

Promise<void>

setStorageAt()

setStorageAt: (args) => Promise<void>

Writes to a slot of an account’s storage.

Example

import { createTestClient, http } from 'viem'
import { foundry } from 'viem/chains'


const client = createTestClient({
  mode: 'anvil',
  chain: 'foundry',
  transport: http(),
})
await client.setStorageAt({
  address: '0xe846c6fcf817734ca4527b28ccb4aea2b6663c79',
  index: 2,
  value: '0x0000000000000000000000000000000000000000000000000000000000000069',
})

Parameters

• args: SetStorageAtParameters

– SetStorageAtParameters

Returns

Promise<void>

signMessage()

signMessage: (args) => Promise<`0x${string}`>

Parameters

• args: SignMessageParameters<TAccountOrAddress extends Account ? Account : undefined>

SignMessageParameters

Returns

Promise<`0x${string}`>

The signed message. SignMessageReturnType

signTransaction()

signTransaction: <chainOverride>(args) => Promise<`0x02${string}` | `0x01${string}` | `0x03${string}` | `0x04${string}` | TransactionSerializedLegacy>

Type Parameters

• chainOverride extends undefined | Chain

Parameters

• args: SignTransactionParameters<TCommon, TAccountOrAddress extends Account ? Account : undefined, chainOverride>

SignTransactionParameters

Returns

Promise<`0x02${string}` | `0x01${string}` | `0x03${string}` | `0x04${string}` | TransactionSerializedLegacy>

The signed message. SignTransactionReturnType

signTypedData()

signTypedData: <typedData, primaryType>(args) => Promise<`0x${string}`>

Type Parameters

• typedData extends object | object

• primaryType extends string

Parameters

• args: SignTypedDataParameters<typedData, primaryType, TAccountOrAddress extends Account ? Account : undefined>

SignTypedDataParameters

Returns

Promise<`0x${string}`>

The signed data. SignTypedDataReturnType

simulateContract()

simulateContract: <abi, functionName, args, chainOverride, accountOverride>(args) => Promise<SimulateContractReturnType<abi, functionName, args, TCommon, TAccountOrAddress extends Account ? Account : undefined, chainOverride, accountOverride>>

Type Parameters

• abi extends Abi | readonly unknown[]

• functionName extends string

• args extends unknown

• chainOverride extends undefined | Chain

• accountOverride extends undefined | `0x${string}` | Account = undefined

Parameters

• args: SimulateContractParameters<abi, functionName, args, TCommon, chainOverride, accountOverride>

SimulateContractParameters

Returns

Promise<SimulateContractReturnType<abi, functionName, args, TCommon, TAccountOrAddress extends Account ? Account : undefined, chainOverride, accountOverride>>

The simulation result and write request. SimulateContractReturnType

snapshot()

snapshot: () => Promise<`0x${string}`>

Snapshot the state of the blockchain at the current block.

Example

import { createTestClient, http } from 'viem'
import { foundry } from 'viem/chains'
import { snapshot } from 'viem/test'


const client = createTestClient({
  mode: 'anvil',
  chain: 'foundry',
  transport: http(),
})
await client.snapshot()

Returns

Promise<`0x${string}`>

stopImpersonatingAccount()

stopImpersonatingAccount: (args) => Promise<void>

Stop impersonating an account after having previously used impersonateAccount.

Example

import { createTestClient, http } from 'viem'
import { foundry } from 'viem/chains'
import { stopImpersonatingAccount } from 'viem/test'


const client = createTestClient({
  mode: 'anvil',
  chain: 'foundry',
  transport: http(),
})
await client.stopImpersonatingAccount({
  address: '0xa5cc3c03994DB5b0d9A5eEdD10CabaB0813678AC',
})

Parameters

• args: StopImpersonatingAccountParameters

– StopImpersonatingAccountParameters

Returns

Promise<void>

switchChain()

switchChain: (args) => Promise<void>

Switch the target chain in a wallet.

Example

import { createWalletClient, custom } from 'viem'
import { mainnet, optimism } from 'viem/chains'


const client = createWalletClient({
  chain: mainnet,
  transport: custom(window.ethereum),
})
await client.switchChain({ id: optimism.id })

Parameters

• args: SwitchChainParameters

SwitchChainParameters

Returns

Promise<void>

tevm

tevm: object & EIP1193Events & object & Eip1193RequestProvider

Low level access to TEVM can be accessed via tevm. These APIs are not guaranteed to be stable.

See

TevmNode

Example

import { createMemoryClient } from 'tevm'


const memoryClient = createMemoryClient()


// low level access to the TEVM VM, blockchain, EVM, stateManager, mempool, receiptsManager and more are available
const vm = await memoryClient.tevm.getVm()
vm.runBlock(...)
const { blockchain, evm, stateManager } = vm
blockchain.addBlock(...)
evm.runCall(...)
stateManager.putAccount(...)


const mempool = await memoryClient.tevm.getTxPool()
const receiptsManager = await memoryClient.tevm.getReceiptsManager()

Type declaration

deepCopy()

readonly deepCopy: () => Promise<TevmNode<"fork" | "normal", object>>

Copies the current client state into a new client

Returns

Promise<TevmNode<"fork" | "normal", object>>

extend()

readonly extend: <TExtension>(decorator) => TevmNode<"fork" | "normal", object & TExtension>

Extends the base client with additional functionality. This enables optimal code splitting and extensibility

Type Parameters

• TExtension extends Record<string, any>

Parameters

• decorator

Returns

TevmNode<"fork" | "normal", object & TExtension>

forkTransport?

readonly optional forkTransport: object

Client to make json rpc requests to a forked node

Example
const client = createMemoryClient({ request: eip1193RequestFn })
forkTransport.request

forkTransport.request: EIP1193RequestFn

getFilters()

readonly getFilters: () => Map<`0x${string}`, Filter>

Gets all registered filters mapped by id

Returns

Map<`0x${string}`, Filter>

getImpersonatedAccount()

readonly getImpersonatedAccount: () => undefined | `0x${string}`

The currently impersonated account. This is only used in fork mode

Returns

undefined | `0x${string}`

getReceiptsManager()

readonly getReceiptsManager: () => Promise<ReceiptsManager>

Interface for querying receipts and historical state

Returns

Promise<ReceiptsManager>

getTxPool()

readonly getTxPool: () => Promise<TxPool>

Gets the pool of pending transactions to be included in next block

Returns

Promise<TxPool>

getVm()

readonly getVm: () => Promise<Vm>

Internal instance of the VM. Can be used for lower level operations. Normally not recomended to use unless building libraries or extensions on top of Tevm.

Returns

Promise<Vm>

logger

readonly logger: Logger

The logger instance

miningConfig

readonly miningConfig: MiningConfig

The configuration for mining. Defaults to ‘auto'

  • 'auto’ will mine a block on every transaction
  • ’interval’ will mine a block every interval milliseconds
  • ’manual’ will not mine a block automatically and requires a manual call to mineBlock
mode

readonly mode: "fork" | "normal"

The mode the current client is running in fork mode will fetch and cache all state from the block forked from the provided URL normal mode will not fetch any state and will only run the EVM in memory

Example
let client = createMemoryClient()
console.log(client.mode) // 'normal'
client = createMemoryClient({ forkUrl: 'https://mainnet.infura.io/v3/your-api-key' })
console.log(client.mode) // 'fork'
ready()

readonly ready: () => Promise<true>

Returns promise that resulves when the client is ready The client is usable without calling this method but may have extra latency on the first call from initialization

Example
const client = createMemoryClient()
await client.ready()
Returns

Promise<true>

removeFilter()

readonly removeFilter: (id) => void

Removes a filter by id

Parameters

• id: `0x${string}`

Returns

void

setFilter()

readonly setFilter: (filter) => void

Creates a new filter to watch for logs events and blocks

Parameters

• filter: Filter

Returns

void

setImpersonatedAccount()

readonly setImpersonatedAccount: (address) => void

Sets the account to impersonate. This will allow the client to act as if it is that account On Ethereum JSON_RPC endpoints. Pass in undefined to stop impersonating

Parameters

• address: undefined | `0x${string}`

Returns

void

status

status: "INITIALIZING" | "READY" | "SYNCING" | "MINING" | "STOPPED"

Returns status of the client

  • INITIALIZING: The client is initializing
  • READY: The client is ready to be used
  • SYNCING: The client is syncing with the forked node
  • MINING: The client is mining a block

Type declaration

emit()

Emit an event.

Parameters

• eventName: keyof EIP1193EventMap

The event name.

• …args: any[]

Arguments to pass to the event listeners.

Returns

boolean

True if the event was emitted, false otherwise.

tevmCall

tevmCall: CallHandler

A powerful low level API for executing calls and sending transactions. See CallParams for options reference. See CallResult for return values reference. Remember, you must set createTransaction: true to send a transaction. Otherwise, it will be a call. You must also mine the transaction before it updates the canonical head state. This can be avoided by setting mining mode to auto when using createMemoryClient.

Example

import { createMemoryClient } from 'tevm'
import { ERC20 } from 'tevm/contract'


const client = createMemoryClient()


const token = ERC20.withAddress(`0x${'0721'.repeat(10)}`)


await client.setAccount(token)


const balance = await client.tevmCall({
  to: token.address,
  data: encodeFunctionData(token.read.balanceOf, [token.address]),
})

In addition to making basic calls, you can also do advanced things like:

  • Impersonate accounts via passing in from, caller, or origin
  • Set the call depth via depth
  • Create a trace or access list using createTrace: true or createAccessList: true
  • Send as a transaction with createTransaction: true For all options see CallParams

tevmContract

tevmContract: ContractHandler

A powerful low level API for calling contracts. Similar to tevmCall but takes care of encoding and decoding data, revert messages, etc. See ContractParams for options reference. See ContractResult for return values reference. Remember, you must set createTransaction: true to send a transaction. Otherwise, it will be a call. You must also mine the transaction before it updates the canonical head state. This can be avoided by setting mining mode to auto when using createMemoryClient.

Example

import { createMemoryClient } from 'tevm'
import { ERC20 } from './MyERC721.sol'


const client = createMemoryClient()
const token = ERC20.withAddress(`0x${'0721'.repeat(10)}`)
await client.setAccount(token)
const balance = await client.tevmContract({
  contract: token,
  method: token.read.balanceOf,
  args: [token.address],
})

In addition to making basic calls, you can also do advanced things like:

  • Impersonate accounts via passing in from, caller, or origin
  • Set the call depth via depth
  • Create a trace or access list using createTrace: true or createAccessList: true
  • Send as a transaction with createTransaction: true For all options see ContractParams

tevmDeploy

tevmDeploy: DeployHandler

Deploys a contract to the EVM with encoded constructor arguments. Extends tevmCall so it supports all advanced options.

See

  • DeployParams for options reference.
  • DeployResult for return values reference. Remember, you must set createTransaction: true to send a transaction. Otherwise, it will be a call. You must also mine the transaction before it updates the canonical head state. This can be avoided by setting mining mode to auto when using createMemoryClient.

Example

import { createMemoryClient } from 'tevm'
import { ERC20 } from './MyERC721.sol'


const client = createMemoryClient()
const token = ERC20.withAddress(`0x${'0721'.repeat(10)}`)


const deploymentResult = await client.tevmDeploy({
  abi: token.abi,
  bytecode: token.bytecode,
  args: ['TokenName', 18, 'SYMBOL'],
})


console.log(deploymentResult.createdAddress)

tevmDumpState

tevmDumpState: DumpStateHandler

Dumps a JSON serializable state from the EVM. This can be useful for persisting and restoring state between processes.

Example

import { createMemoryClient } from 'tevm'
import fs from 'fs'
const client = createMemoryClient()
const state = await client.tevmDumpState()
fs.writeFileSync('state.json', JSON.stringify(state))

tevmGetAccount

tevmGetAccount: GetAccountHandler

Gets the account state of an account. It does not return the storage state by default but can if returnStorage is set to true. In forked mode, the storage is only the storage TEVM has cached and may not represent all the on-chain storage.

See

Example

import { createMemoryClient } from 'tevm'


const client = createMemoryClient()


const account = await client.tevmGetAccount({
  address: `0x${'0000'.repeat(10)}`,
  returnStorage: true,
})

tevmLoadState

tevmLoadState: LoadStateHandler

Loads a JSON serializable state into the EVM. This can be useful for persisting and restoring state between processes.

Example

import { createMemoryClient } from 'tevm'
import fs from 'fs'


const client = createMemoryClient()


const state = fs.readFileSync('state.json', 'utf8')


await client.tevmLoadState(state)

tevmMine

tevmMine: MineHandler

Mines a new block with all pending transactions. In manual mode you must call this manually before the canonical head state is updated.

Example

import { createMemoryClient } from 'tevm'


const client = createMemoryClient()


await client.tevmMine()

tevmReady()

tevmReady: () => Promise<true>

Returns a promise that resolves when the TEVM is ready. This is not needed to explicitly be called as all actions will wait for the TEVM to be ready.

Example

import { createMemoryClient } from 'tevm'


const client = createMemoryClient()


await client.tevmReady()

Same as calling client.tevm.ready()

Returns

Promise<true>

tevmScript

tevmScript: ScriptHandler

Example

import { createMemoryClient } from 'tevm'
import { ERC20 } from './MyERC721.sol'


const client = createMemoryClient()


const balance = await client.tevmContract({
  createTransaction: true,
  deployedBytecode: ERC20.deployedBytecode,
  abi: ERC20.abi,
  method: 'mint',
  args: [client.address, 1n],
})

tevmSetAccount

tevmSetAccount: SetAccountHandler

Sets any property of an account including its balance, nonce, contract deployedBytecode, contract state, and more.

See

Example

import { createMemoryClient, numberToHex } from 'tevm'
import { SimpleContract } from 'tevm/contract'


const client = createMemoryClient()


await client.tevmSetAccount({
  address: `0x${'0123'.repeat(10)}`,
  balance: 100n,
  nonce: 1n,
  deployedBytecode: SimpleContract.deployedBytecode,
  state: {
    [`0x${'0'.repeat(64)}`]: numberToHex(420n),
  }
})

transport

transport: TransportConfig<string> & object

The RPC transport

Type declaration

tevm

tevm: object & EIP1193Events & object & object

Type declaration
deepCopy()

readonly deepCopy: () => Promise<TevmNode<"fork" | "normal", object>>

Copies the current client state into a new client

Returns

Promise<TevmNode<"fork" | "normal", object>>

extend()

readonly extend: <TExtension>(decorator) => TevmNode<"fork" | "normal", object & TExtension>

Extends the base client with additional functionality. This enables optimal code splitting and extensibility

Type Parameters

• TExtension extends Record<string, any>

Parameters

• decorator

Returns

TevmNode<"fork" | "normal", object & TExtension>

forkTransport?

readonly optional forkTransport: object

Client to make json rpc requests to a forked node

Example
const client = createMemoryClient({ request: eip1193RequestFn })
forkTransport.request

forkTransport.request: EIP1193RequestFn

getFilters()

readonly getFilters: () => Map<`0x${string}`, Filter>

Gets all registered filters mapped by id

Returns

Map<`0x${string}`, Filter>

getImpersonatedAccount()

readonly getImpersonatedAccount: () => undefined | `0x${string}`

The currently impersonated account. This is only used in fork mode

Returns

undefined | `0x${string}`

getReceiptsManager()

readonly getReceiptsManager: () => Promise<ReceiptsManager>

Interface for querying receipts and historical state

Returns

Promise<ReceiptsManager>

getTxPool()

readonly getTxPool: () => Promise<TxPool>

Gets the pool of pending transactions to be included in next block

Returns

Promise<TxPool>

getVm()

readonly getVm: () => Promise<Vm>

Internal instance of the VM. Can be used for lower level operations. Normally not recomended to use unless building libraries or extensions on top of Tevm.

Returns

Promise<Vm>

logger

readonly logger: Logger

The logger instance

miningConfig

readonly miningConfig: MiningConfig

The configuration for mining. Defaults to ‘auto'

  • 'auto’ will mine a block on every transaction
  • ’interval’ will mine a block every interval milliseconds
  • ’manual’ will not mine a block automatically and requires a manual call to mineBlock
mode

readonly mode: "fork" | "normal"

The mode the current client is running in fork mode will fetch and cache all state from the block forked from the provided URL normal mode will not fetch any state and will only run the EVM in memory

Example
let client = createMemoryClient()
console.log(client.mode) // 'normal'
client = createMemoryClient({ forkUrl: 'https://mainnet.infura.io/v3/your-api-key' })
console.log(client.mode) // 'fork'
ready()

readonly ready: () => Promise<true>

Returns promise that resulves when the client is ready The client is usable without calling this method but may have extra latency on the first call from initialization

Example
const client = createMemoryClient()
await client.ready()
Returns

Promise<true>

removeFilter()

readonly removeFilter: (id) => void

Removes a filter by id

Parameters

• id: `0x${string}`

Returns

void

setFilter()

readonly setFilter: (filter) => void

Creates a new filter to watch for logs events and blocks

Parameters

• filter: Filter

Returns

void

setImpersonatedAccount()

readonly setImpersonatedAccount: (address) => void

Sets the account to impersonate. This will allow the client to act as if it is that account On Ethereum JSON_RPC endpoints. Pass in undefined to stop impersonating

Parameters

• address: undefined | `0x${string}`

Returns

void

status

status: "INITIALIZING" | "READY" | "SYNCING" | "MINING" | "STOPPED"

Returns status of the client

  • INITIALIZING: The client is initializing
  • READY: The client is ready to be used
  • SYNCING: The client is syncing with the forked node
  • MINING: The client is mining a block
Type declaration
emit()

Emit an event.

Parameters

• eventName: keyof EIP1193EventMap

The event name.

• …args: any[]

Arguments to pass to the event listeners.

Returns

boolean

True if the event was emitted, false otherwise.

Type declaration
request

request: EIP1193RequestFn

type

type: string

The type of client.

uid

uid: string

A unique ID for the client.

uninstallFilter()

uninstallFilter: (args) => Promise<boolean>

Parameters

• args: UninstallFilterParameters

UninstallFilterParameters

Returns

Promise<boolean>

A boolean indicating if the Filter was successfully uninstalled. UninstallFilterReturnType

verifyMessage()

verifyMessage: (args) => Promise<boolean>

Parameters

• args

• args.address: `0x${string}`

The address that signed the original message.

• args.blockNumber?: bigint

The balance of the account at a block number.

• args.blockTag?: BlockTag

The balance of the account at a block tag.

Default

'latest'

• args.factory?: `0x${string}`

• args.factoryData?: `0x${string}`

• args.message: SignableMessage

The message to be verified.

• args.signature: `0x${string}` | Uint8Array | Signature

The signature that was generated by signing the message with the address’s private key.

Returns

Promise<boolean>

Whether or not the signature is valid. VerifyMessageReturnType

verifySiweMessage()

verifySiweMessage: (args) => Promise<boolean>

Parameters

• args

• args.address?: `0x${string}`

Ethereum address to check against.

• args.blockNumber?: bigint

The balance of the account at a block number.

• args.blockTag?: BlockTag

The balance of the account at a block tag.

Default

'latest'

• args.domain?: string

RFC 3986 authority to check against.

• args.message: string

EIP-4361 formatted message.

• args.nonce?: string

Random string to check against.

• args.scheme?: string

RFC 3986 URI scheme to check against.

• args.signature: `0x${string}`

Signature to check against.

• args.time?: Date

Current time to check optional expirationTime and notBefore fields.

Default

new Date()

Returns

Promise<boolean>

Whether or not the signature is valid. VerifySiweMessageReturnType

verifyTypedData()

verifyTypedData: (args) => Promise<boolean>

Parameters

• args: VerifyTypedDataParameters

Returns

Promise<boolean>

Whether or not the signature is valid. VerifyTypedDataReturnType

waitForTransactionReceipt()

waitForTransactionReceipt: (args) => Promise<ExtractChainFormatterReturnType<TCommon, "transactionReceipt", TransactionReceipt>>

Parameters

• args: WaitForTransactionReceiptParameters<TCommon>

WaitForTransactionReceiptParameters

Returns

Promise<ExtractChainFormatterReturnType<TCommon, "transactionReceipt", TransactionReceipt>>

The transaction receipt. WaitForTransactionReceiptReturnType

watchAsset()

watchAsset: (args) => Promise<boolean>

Parameters

• args: WatchAssetParams

WatchAssetParameters

Returns

Promise<boolean>

Boolean indicating if the token was successfully added. WatchAssetReturnType

watchBlockNumber()

watchBlockNumber: (args) => WatchBlockNumberReturnType

Parameters

• args: WatchBlockNumberParameters

WatchBlockNumberParameters

Returns

WatchBlockNumberReturnType

A function that can be invoked to stop watching for new block numbers. WatchBlockNumberReturnType

watchBlocks()

watchBlocks: <includeTransactions, blockTag>(args) => WatchBlocksReturnType

Type Parameters

• includeTransactions extends boolean = false

• blockTag extends BlockTag = "latest"

Parameters

• args: WatchBlocksParameters<TevmTransport, TCommon, includeTransactions, blockTag>

WatchBlocksParameters

Returns

WatchBlocksReturnType

A function that can be invoked to stop watching for new block numbers. WatchBlocksReturnType

watchContractEvent()

watchContractEvent: <abi, eventName, strict>(args) => WatchContractEventReturnType

Type Parameters

• abi extends Abi | readonly unknown[]

• eventName extends string

• strict extends undefined | boolean = undefined

Parameters

• args: WatchContractEventParameters<abi, eventName, strict, TevmTransport>

WatchContractEventParameters

Returns

WatchContractEventReturnType

A function that can be invoked to stop watching for new event logs. WatchContractEventReturnType

watchEvent()

watchEvent: <abiEvent, abiEvents, strict>(args) => WatchEventReturnType

Type Parameters

• abiEvent extends undefined | AbiEvent = undefined

• abiEvents extends undefined | readonly unknown[] | readonly AbiEvent[] = abiEvent extends AbiEvent ? [abiEvent<abiEvent>] : undefined

• strict extends undefined | boolean = undefined

Parameters

• args: WatchEventParameters<abiEvent, abiEvents, strict, TevmTransport>

WatchEventParameters

Returns

WatchEventReturnType

A function that can be invoked to stop watching for new Event Logs. WatchEventReturnType

watchPendingTransactions()

watchPendingTransactions: (args) => WatchPendingTransactionsReturnType

Parameters

• args: WatchPendingTransactionsParameters<TevmTransport>

WatchPendingTransactionsParameters

Returns

WatchPendingTransactionsReturnType

A function that can be invoked to stop watching for new pending transaction hashes. WatchPendingTransactionsReturnType

writeContract()

writeContract: <abi, functionName, args, chainOverride>(args) => Promise<`0x${string}`>

Type Parameters

• abi extends Abi | readonly unknown[]

• functionName extends string

• args extends unknown

• chainOverride extends undefined | Chain = undefined

Parameters

• args: WriteContractParameters<abi, functionName, args, TCommon, TAccountOrAddress extends Account ? Account : undefined, chainOverride>

WriteContractParameters

Returns

Promise<`0x${string}`>

A Transaction Hash. WriteContractReturnType

Defined in

packages/memory-client/src/createMemoryClient.js:189