openzeppelin-contracts/test/helpers/expectEvent.js

const should = require('chai').should();

function inLogs (logs, eventName, eventArgs = {}) {
  const event = logs.find(e => e.event === eventName);
  should.exist(event);
  for (const [k, v] of Object.entries(eventArgs)) {
    should.exist(event.args[k]);
    event.args[k].should.equal(v);
  }
  return event;
}

async function inTransaction (tx, eventName, eventArgs = {}) {
  const { logs } = await tx;
  return inLogs(logs, eventName, eventArgs);
}

module.exports = {
  inLogs,
  inTransaction,
};