I'm working on a Tron smart contract and am providing a function in my tests file which emits to an event. When trying to console.log the logs I get an empty array. Is this because of lag for the transaction to hit the shasta network or is there something else I'm overlooking? I am using tronbox test --network shasta.

Here is a bare bones test version of my contract:

pragma solidity >=0.5.0 <0.7.0;

contract TronStack {
    uint public investmentCount;
    mapping (uint => Investment) public investments;

    struct Investment {
        uint id;
        uint amount;

    event InvestmentCreated (
        uint id,
        uint amount

    constructor() public {

    function invest(uint _amount) public {
        investments[investmentCount] = Investment(investmentCount, _amount);
        emit InvestmentCreated(investmentCount, _amount);


And here is my js test file:

const TronStack = artifacts.require('./TronStack.sol')
const TronWeb = require('tronweb')

contract('TronStack', (accounts) => {
    let tronstack

    before(async () => {
        tronstack = await TronStack.deployed()

    describe('deployment', async () => {
        it('deploys successfully', async () => {
            const address = await tronstack.address
            assert.notEqual(address, 0x0)
            assert.notEqual(address, '')
            assert.notEqual(address, null)
            assert.notEqual(address, undefined)

            addressTron = tronWeb.address.fromHex(address)
            console.log(addressTron) // returns contract address

    describe('investments', async () => {
        let result, event, investmentCount

        before(async () => {
            result = await tronstack.invest('10000000')
            event = await tronWeb.getEventByTransactionID(result)

            investmentCount = await tronstack.investmentCount()

        it('adds investment', async () => {
            assert.equal(investmentCount, 1)

            console.log(result) // returns tx id
            console.log(event) // returns empty array

            // using a previous tx id prints logs as intended
            oldTX = await tronWeb.getEventByTransactionID('0c960b698ffc889c1c7df81dc2f09eace47d50c73ffc662c2e3fb1671c4515c4')



The test returns something like this:

  Contract: TronStack
      ✓ deploys successfully
    block: 7796397,
    timestamp: 1599495159000,
    contract: 'TAoE543WH1fVerZRHK5ecsKU2VPckE5mLw',
    name: 'InvestmentCreated',
    transaction: '0c960b698ffc889c1c7df81dc2f09eace47d50c73ffc662c2e3fb1671c4515c4',
    result: { '0': '1', '1': '10000000', amount: '10000000', id: '1' },
    resourceNode: 'solidityNode'
      ✓ adds investment (133ms)

  2 passing (956ms)

1 Answer 1


I noticed that if you create a transaction with tronweb on shasta network it takes a bit to see the same transaction on shasta tronscan. The same happens when you also create a contract.

So to solve this I just wait 5s each time I'm interacting with the smart contract:

 let tx = await contract.createToken(tokenType.code, token.reference_identifier).send()

        await setTimeout(async () => {
            await tronWeb.getEventByTransactionID(tx).then((result) => {
        }, 5000)

I don't like to have those types of timeouts in my code, but it works and I just hope that you don't have those issues in mainnet.

EDIT: I noticed that sometimes 5 seconds wasn't enough, so I also added a do while to be sure to always receive the transaction event

        // Wait 5 seconds for the transaction to propagate
        await this.sleep(5000)
        // Also do a do while, so we are sure that we get the tx event
        let result
        do {
            result = await tronWeb.getEventByTransactionID(tx).then((result) => result)
        } while (result.length === 0)

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