viem/utils/getAction.ts

TypeScript Interface for Ethereum

import type { Client } from '../clients/createClient.js'
import type { PublicActions } from '../clients/decorators/public.js'
import type { WalletActions } from '../clients/decorators/wallet.js'
import type { Transport } from '../clients/transports/createTransport.js'
import type { Account } from '../types/account.js'
import type { Chain } from '../types/chain.js'
import type { RpcSchema } from '../types/eip1193.js'

/**
 * Retrieves and returns an action from the client (if exists), and falls
 * back to the tree-shakable action.
 *
 * Useful for extracting overridden actions from a client (ie. if a consumer
 * wants to override the `sendTransaction` implementation).
 */
export function getAction<
  transport extends Transport,
  chain extends Chain | undefined,
  account extends Account | undefined,
  rpcSchema extends RpcSchema | undefined,
  extended extends { [key: string]: unknown },
  client extends Client<transport, chain, account, rpcSchema, extended>,
  parameters,
  returnType,
>(
  client: client,
  actionFn: (_: any, parameters: parameters) => returnType,
  // Some minifiers drop `Function.prototype.name`, or replace it with short letters,
  // meaning that `actionFn.name` will not always work. For that case, the consumer
  // needs to pass the name explicitly.
  name: keyof PublicActions | keyof WalletActions | (string & {}),
): (parameters: parameters) => returnType {
  const action_implicit = client[actionFn.name]
  if (typeof action_implicit === 'function')
    return action_implicit as (params: parameters) => returnType

  const action_explicit = client[name]
  if (typeof action_explicit === 'function')
    return action_explicit as (params: parameters) => returnType

  return (params) => actionFn(client, params)
}