Testing basic contract on truffle

[pbirbarah]

Discussed in https://github.com/orgs/trufflesuite/discussions/5178

^{Originally posted by pbirbarah June 5, 2022}
this is my first contract and I am using truffle with ganache for testing and I am facing some issues:

The contract is supposed to just send payment back to the person who contacts it.
How do I do that? I have the contract deployed, created an instance const my_contract = await Test_Payment.deployed()

when I try my_contract.test I get an error that this is not a function I am confused how to proceed.

[kimanikelly]

Hi, @pbirbarah do you have a public repository or full code snippet of Test_Payment.sol? I would like to assist you with the blocker you're facing thank you.

[pbirbarah]

thanks a lot. please use this link https://www.toptal.com/developers/hastebin/vofixocoxi.php

[kimanikelly]

@pbirbarah Sounds great thank you, I will let you know what I find and we can go over the solution

[kimanikelly]

Hi, @pbirbarah I performed unit tests for the test function and found it to be properly working while sending 0.001 ETH as the value. The environment I'm using is Hardhat so the syntax might be a little different. I added the code for the test process and a screenshot of the test passing including the before and after ETH balance of the connected signer that is invoking the function. I do have concerns about how the test function operates, the signer invoking the test function has to send 0.001 ETH to TestPayment.sol and in turn, TestPayment.sol sends the 0.001 ETH back to the msg.sender taking in account the gas fees to invoke the function is being subtracted from signers balance.

import { SignerWithAddress } from "@nomiclabs/hardhat-ethers/signers";
import { expect, use } from "chai";
import { solidity } from "ethereum-waffle";
import { ethers } from "hardhat";
import { TestPayment } from "../typechain";

use(solidity);

describe.only("Test Payment", function () {
  let testPayment: TestPayment;
  let signers: SignerWithAddress[];

  beforeEach(async () => {
    signers = await ethers.getSigners();

    const TestPayment = await ethers.getContractFactory(
      "TestPayment",
      signers[0]
    );

    testPayment = (await TestPayment.deploy()) as TestPayment;
  });

  it("Should invoke the test() function", async () => {
    // Return the ETH balance of TestPayment before invoke test()
    const preContractBal = await ethers.provider.getBalance(
      testPayment.address
    );

    // Expect the ETH balance to equal 0
    expect(preContractBal).to.equal(0);

    const signerPreBal = await signers[0].getBalance();

    // Invoke test() with .001 ETH
    await testPayment.test({ value: BigInt(1e15) });

    const signerPostBal = await signers[0].getBalance();

    // Return the ETH balance of TestPayment after invoke test()
    const postContractBal = await ethers.provider.getBalance(
      testPayment.address
    );

    // Expect the ETH balance to equal 0
    expect(postContractBal).to.equal(0);

    console.log({
      signerPreBal: signerPreBal,
      signerPostBal: signerPostBal,
    });
  });
});

[kimanikelly]

@pbirbarah How are you deploying your contract do you have a code snippet?

[pbirbarah]

I am using truffle console with ganache so it's different.

after deploying the contract on ganache, I can write this to double check it is deployed.
const my_contract = await Test_Payment.deployed()
then I try and define the sender address using
address my_address = '0x56cFBBDB11D385da02db4eef2784E021435d6731' and I get an error

[kimanikelly]

@pbirbarah Alright I will try with Truffle and let you know

[kimanikelly]

@pbirbarah Before I deployed the contract and invoked the test function on localhost through truffle console and ganache-cli I was able to successfully invoke test through the test suite by configuring a init test file and executing the truffle test command

const TestPayment = artifacts.require("TestPayment");

contract("TestPayment", (accounts) => {
  it("Should invoke the test() function", async () => {
    const testPayment = await TestPayment.deployed();

    await testPayment.test({ value: 1e15 });
  });
});

[kimanikelly]

@pbirbarah I was able to successfully deploy TestPayment.sol locally with truffle migrate and ganache-cli then invoke the test function

[pbirbarah]

this is very helpful thank you. How can I specify which address to send from using the console? and can I check the balance on the address using the console?

[kimanikelly]

@pbirbarah The Truffle console supports the accounts variable and returns an array of public addresses connected to ganache-cli. You can specify which address invokes the test function by adding the from property to the function call and designating the index inside the accounts array.

c

[kimanikelly]

@pbirbarah Here is how you can check the ETH balance from one of the accounts

[pbirbarah]

that is perfect! thanks!

[kimanikelly]

@pbirbarah No problem take care