simulate.simulateCalls

Simulates execution of a batch of calls in a single block via tempo_simulateV1.

A convenience wrapper around simulate.simulateBlocks that runs all calls in a single block and returns flattened results.

Usage

import { parseUnits } from 'viem'
import { Actions, Addresses } from 'viem/tempo'
import { client } from './viem.config'
 
const { results, tokenMetadata } = await client.simulate.simulateCalls({
  calls: [
    Actions.token.approve.call({
      token: '0x20c0000000000000000000000000000000000001',
      spender: Addresses.stablecoinDex,
      amount: parseUnits('100', 6),
    }),
    Actions.dex.buy.call({
      tokenIn: '0x20c0000000000000000000000000000000000001',
      tokenOut: '0x20c0000000000000000000000000000000000002',
      amountOut: parseUnits('10', 6),
      maxAmountIn: parseUnits('100', 6),
    }),
    Actions.token.transfer.call({
      token: '0x20c0000000000000000000000000000000000002',
      to: '0x742d35Cc6634C0532925a3b844Bc9e7595f0bEbb',
      amount: parseUnits('10', 6),
    }),
  ],
  traceTransfers: true,
})

import { Account, createClient } from 'viem/tempo'
 
export const client = createClient({
  account: Account.fromSecp256k1('0x...'),
})

Return Type

type ReturnType = {
  /** Block metadata for the simulated block. */
  block: Block
  /** Call results. */
  results: {
    /** Encoded return data. */
    data: Hex
    /** Gas consumed by the call. */
    gasUsed: bigint
    /** Logs emitted by the call. */
    logs?: Log[]
    /** Decoded result (if ABI provided). */
    result: unknown
    /** Call status. */
    status: 'success' | 'failure'
    /** Error (if status is 'failure'). */
    error?: Error
  }[]
  /** Token metadata for TIP-20 tokens involved in the simulation. */
  tokenMetadata: Record<Address, {
    name: string
    symbol: string
    currency: string
  }>
}

Parameters

calls

• Type: Call[]

Calls to simulate. Supports ABI-encoded calls (with abi, functionName, args) or raw calls (with to, data). Use .call() helpers from other actions for ergonomic usage.

account (optional)

• Type: Account | Address

Account attached to all calls (msg.sender). Falls back to the client account if not provided.

stateOverrides (optional)

• Type: StateOverride[]

Account state overrides for the simulation.

traceTransfers (optional)

• Type: boolean

Whether to trace token transfers. When enabled, the response includes tokenMetadata for all TIP-20 tokens involved.

validation (optional)

• Type: boolean

Whether to enable validation mode.

blockNumber (optional)

• Type: bigint

Block number to simulate against.

blockTag (optional)

• Type: BlockTag
• Default: "latest"

Block tag to simulate against.