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This tutorial will show you how to deploy a solidity contract to Ropsten (Test Net).


Installing node and npm, here is a great tutorial but most of you should already have this setup

Install web3 and solc.

npm install -g web3 solc fs

Register with Endpoint

get test eth

Possible issues

Error: Cannot find module ‘web3’

Could be that you not adding the node modules to your path export NODE_PATH=/home/plouw/.node_modules_global/lib/node_modules

Make use of the OpenZeppelin expectThrow script

export default async promise => {
  try {
    await promise;
  } catch (error) {
    // TODO: Check jump destination to destinguish between a throw
    //       and an actual invalid jump.
    const invalidOpcode ='invalid opcode') >= 0;
    // TODO: When we contract A calls contract B, and B throws, instead
    //       of an 'invalid jump', we get an 'out of gas' error. How do
    //       we distinguish this from an actual out of gas event? (The
    //       ganache log actually show an 'invalid jump' event.)
    const outOfGas ='out of gas') >= 0;
    const revert ='revert') >= 0;
      invalidOpcode || outOfGas || revert,
      'Expected throw, got \'' + error + '\' instead',
  }'Expected throw not received');

In my test I have added that code to file in my test folder /helpers/expectThrow.js and have used as follow. Here the function getPeriodStartTimestamp is expected to throw when the value is 50000 or larger.

// Import the helper script
import expectThrow from './helpers/expectThrow';

const PeriodUtilWeek = artifacts.require("./PeriodUtilWeek.sol");

const BigNumber = web3.BigNumber;

contract('PeriodUtilWeek',function(accounts) {

  // Other tests

  describe('Test getPeriodStartTimestamp (Week)', async function() {

    beforeEach(async function () {
      this.periodUtilWeek = await;

    it('Test exception', async function() {
      // Magic bit here!
      await expectThrow(this.periodUtilWeek.getPeriodStartTimestamp(new BigNumber('50000')));

  // Loads more tests

Fun Issue

Unexpected token import! This is because we need some Babel

(function (exports, require, module, __filename, __dirname) { import expectThrow from './helpers/expectThrow';
SyntaxError: Unexpected token import
    at createScript (vm.js:80:10)
    at Object.runInThisContext (vm.js:139:10)
    at Module._compile (module.js:616:28)
    at loader (/home/mmmmmm/dev/Project/solidityWork/profit/node_modules/babel-register/lib/node.js:144:5)
    at Object.require.extensions.(anonymous function) [as .js] (/home/mmmmmm/dev/Project/solidityWork/profit/node_modules/babel-register/lib/node.js:154:7)
    at Module.load (module.js:565:32)
    at tryModuleLoad (module.js:505:12)
    at Function.Module._load (module.js:497:3)
    at Module.require (module.js:596:17)
    at require (internal/module.js:11:18)
    at /home/mmmmmm/.node_modules_global/lib/node_modules/truffle/node_modules/mocha/lib/mocha.js:231:27
    at Array.forEach (<anonymous>)
    at Mocha.loadFiles (/home/mmmmmm/.node_modules_global/lib/node_modules/truffle/node_modules/mocha/lib/mocha.js:228:14)
    at (/home/mmmmmm/.node_modules_global/lib/node_modules/truffle/node_modules/mocha/lib/mocha.js:536:10)
    at /home/mmmmmm/.node_modules_global/lib/node_modules/truffle/build/webpack:/~/truffle-core/lib/test.js:125:1
    at <anonymous>
    at process._tickCallback (internal/process/next_tick.js:188:7)

To fix this add the following dependencies by editing package.json and adding under “devDependencies” the following

"babel-polyfill": "^6.23.0",
"babel-preset-es2015": "^6.18.0",
"babel-preset-stage-2": "^6.18.0",
"babel-preset-stage-3": "^6.17.0",

Running npm install in the project directory to install the new packages

npm install

Create a new file in the project directory call .babelrc and put the following in there

  "presets": ["es2015", "stage-2", "stage-3"]

Now when you run the truffle test all should work again without a error

Update (2018-06-11)

Code coverage will stop working with same issue SyntaxError: Unexpected token import. To fix this add a network coverage to the truffle.js, see below example:


module.exports = {
  // See <>
  // to customize your Truffle configuration!
  networks: {
    mainnet: {
      host: 'localhost',
      port: 8545,
      network_id: '1', // Match any network id
      gas: 3500000,
      gasPrice: 10000000000
    development: {
      host: "localhost",
      port: 7545,
      network_id: "*", // Match any network id
      gas: 4500000,
    coverage: {
      host: "localhost",
      port: 7545,
      network_id: "*", // Match any network id
      gas: 4500000,
    ropsten : {
      host: "",
      port: 8545,
      network_id: "3", // Match any network id
      gas: 4500000,
  dependencies: {},
  solc: {
    optimizer: {
      enabled: true,
      runs: 200,