Factory file fails to compile when type `uint256[]` is used in the constructor

The generated ConstructorWithIntArrayFactory.ts file for the following Solidity will fail to compile as the BigNumberish type is not imported from ethers/utils

contract ConstructorWithIntArray {

    uint256[] someArray;

    constructor(uint256[] memory _someArray) public {
        someArray = _someArray;
    }
}

The generated ConstructorWithIntArrayFactory.ts file is

/* Generated by ts-generator ver. 0.0.8 */
/* tslint:disable */

import { Contract, ContractFactory, Signer } from "ethers";
import { Provider } from "ethers/providers";
import { UnsignedTransaction } from "ethers/utils/transaction";

import { ConstructorWithIntArray } from "./ConstructorWithIntArray";

export class ConstructorWithIntArrayFactory extends ContractFactory {
  constructor(signer?: Signer) {
    super(_abi, _bytecode, signer);
  }
  deploy(_someArray: (BigNumberish)[]): Promise<ConstructorWithIntArray> {
    return super.deploy(_someArray) as Promise<ConstructorWithIntArray>;
  }
  getDeployTransaction(_someArray: (BigNumberish)[]): UnsignedTransaction {
    return super.getDeployTransaction(_someArray);
  }
  attach(address: string): ConstructorWithIntArray {
    return super.attach(address) as ConstructorWithIntArray;
  }
  connect(signer: Signer): ConstructorWithIntArrayFactory {
    return super.connect(signer) as ConstructorWithIntArrayFactory;
  }
  static connect(
    address: string,
    signerOrProvider: Signer | Provider
  ): ConstructorWithIntArray {
    return new Contract(
      address,
      _abi,
      signerOrProvider
    ) as ConstructorWithIntArray;
  }
}

const _abi = [
  {
    inputs: [
      {
        internalType: "uint256[]",
        name: "_someArray",
        type: "uint256[]"
      }
    ],
    payable: false,
    stateMutability: "nonpayable",
    type: "constructor"
  }
];

const _bytecode =
  "0x608060405234801561001057600080fd5b5060405161018f38038061018f8339818101604052602081101561003357600080fd5b810190808051604051939291908464010000000082111561005357600080fd5b90830190602082018581111561006857600080fd5b825186602082028301116401000000008211171561008557600080fd5b82525081516020918201928201910280838360005b838110156100b257818101518382015260200161009a565b5050505091909101604052505082516100d492506000915060208401906100db565b5050610143565b828054828255906000526020600020908101928215610116579160200282015b828111156101165782518255916020019190600101906100fb565b50610122929150610126565b5090565b61014091905b80821115610122576000815560010161012c565b90565b603e806101516000396000f3fe6080604052600080fdfea265627a7a72315820311701576656af678908509fac0c466c381c9bd65f0f04fa674cdf92fb1ab24c64736f6c634300050b0032";

The typescript errors are

Error:(14, 23) TS2304: Cannot find name 'BigNumberish'.
Error:(17, 37) TS2304: Cannot find name 'BigNumberish'.

The workaround is to include a dummy constructor parameter of type uint256 so the BigNumberish type is imported in the factory type definition file.

[quezak]

Actually, this should be a bit better, and not too complicated: /\WBigNumberish(\W|$)/ It should exclude all sane false positives where BigNumberish is found in the arg name, but not in the types – see last example here: https://regex101.com/r/WeFMHp/2

[naddison36]

The problem is with this line in the Ethers generator https://github.com/ethereum-ts/TypeChain/blob/master/lib/targets/ethers/generation.ts#L84

if (constructorArgs.match(/: BigNumberish/)) ethersUtilsImports.push("BigNumberish");

For the above example, the constructorArgs will have value _someArray: (BigNumberish)[], which will not match /: BigNumberish/. I’d suggest just matching on /BigNumberish/ as the BigNumberish could be in a multidimensional array or a struct.

I was going to raise a PR but I can’t get the tests to work before I do my change.