MyCrypto/common/libs/wallet/privkey.js

// @flow
import BaseWallet from './base';
import { privateToPublic, publicToAddress, toChecksumAddress } from 'ethereumjs-util';

export type PrivateKeyUnlockParams = {
    key: string,
    password: string
};

export default class PrivKeyWallet extends BaseWallet {
    privKey: Buffer;
    pubKey: Buffer;
    address: Buffer;
    constructor(params: PrivateKeyUnlockParams) {
        super();
        this.privKey = Buffer.from(params.key, 'hex');
        this.pubKey = privateToPublic(this.privKey);
        this.address = publicToAddress(this.pubKey);
    }

    getAddress() {
        return toChecksumAddress(`0x${this.address.toString('hex')}`);
    }
}