xavierlepretre

"use strict";

/**
 * @param {!Function.<!Promise>} action.
 * @param {!Number | !string | !BigNumber} gasToUse.
 * @returns {!Promise} which throws unless it hit a valid error.
 */
module.exports = function expectedExceptionPromise(action, gasToUse) {
    return new Promise(function (resolve, reject) {
            try {

xavierlepretre

web3.eth.filter("pending").watch(function() {
    if (eth.mining) return;
    console.log(new Date() + "-- Transactions detected, so starting mining.");
    miner.start(1);
});

web3.eth.filter('latest', function(error, result) {
    console.log(new Date() + "-- Got latest, so stopping mining");
    miner.stop();
    if (txpool.status.pending > 0) {

xavierlepretre

const Rx = require('rx');

module.exports = {
    rxify: function (web3) {
        // List synchronous functions masquerading as values.
        var syncGetters = {
            db: [],
            eth: [ "accounts", "blockNumber", "coinbase", "gasPrice", "hashrate",
                "mining", "protocolVersion", "syncing" ],
            net: [ "listening", "peerCount" ],

xavierlepretre

const Promise = require("bluebird");

/**
 * @param {!Array.<function.Promise.<Any>>} promiseArray.
 * @returns {!Promise.<Array.<Any>>} The results of the promises passed to the function.
 */
module.exports = function sequentialPromise(promiseArray) {
    const result = promiseArray.reduce(
        (reduced, promise, index) => {
            reduced.results.push(undefined);

xavierlepretre

const Promise = require("bluebird");

/**
 * @param {!Object.<function.<Promise.<Any>>>} promiseObject. Each key maps to a function
 * that returns a promise.
 * @returns {!Promise.<Object.<Any>>} The results of the promises passed to the function.
 */
module.exports = function sequentialPromiseNamed(promiseObject) {
    const result = Object.keys(promiseObject).reduce(
        (reduced, key) => {

xavierlepretre

"use strict";

const Rx = require('rx');

module.exports = function addFilterObservableToWeb3(web3) {

    web3.eth.filterObservable = function(_options) {
        const filter = web3.eth.filter(_options);

        return Rx.Observable.create(function(observer) {

spalladino

Falsehoods that Ethereum programmers believe

I recently stumbled upon Falsehoods programmers believe about time zones, which got a good laugh out of me. It reminded me of other great lists of falsehoods, such as about names or time, and made me look for an equivalent for Ethereum. Having found none, here is my humble contribution to this set.

About Gas

Calling estimateGas will return the gas required by my transaction

Calling estimateGas will return the gas that your transaction would require if it were mined now. The current state of the chain may be very different to the state in which your tx will get mined. So when your tx i

hrkrshnn

Upgrade to at least 0.8.4

Using newer compiler versions and the optimizer gives gas optimizations and additional safety checks for free!

The advantages of versions 0.8.* over <0.8.0 are:

• Safemath by default from 0.8.0 (can be more gas efficient than some library based safemath).
• Low level inliner from 0.8.2, leads to cheaper runtime gas. Especially relevant when the contract has small functions. For