Error verifying ERC20 without constructor arguments on Etherscan

Support Contracts
7

Hi @IAMDEJEAN,

I used the following method to verify: Verify smart contract inheriting from OpenZeppelin Contracts

First I deployed the contract to Goerli testnet.

I then converted your contract to use package imports

pragma solidity ^0.5.0;

import "@openzeppelin/contracts/token/ERC20/ERC20.sol";
import "@openzeppelin/contracts/token/ERC20/ERC20Detailed.sol";

contract YelmiToken is ERC20, ERC20Detailed {

    constructor () public ERC20Detailed("YelmiToken", "YLT", 18) {
        _mint(msg.sender, 1000000 * (10 ** uint256(decimals())));
    }
}

I then installed OpenZeppelin Contracts 2.5 to a buidler project

$ npm i @openzeppelin/contracts@2.5.0

With the buidler etherscan plugin installed I then verified:

$ npx buidler verify --network goerli 0xAF53B91508003D6875b00Da470808f2dB53F1A5E
Compiling...
Successfully submitted source code for contract
contracts/YelmiToken.sol:YelmiToken at 0xAF53B91508003D6875b00Da470808f2dB53F1A5E
for verification on etherscan. Waiting for verification result...
Successfully verified contract on etherscan

I also verified on Ropsten, which I assume you had deployed to, so your token will now be verified.