Lesson 6 - (14) Solidity Coverage

[musubomair]

Hey guys!

At the end of the lesson 6 chapter, Patrick tells us to try writing the last test task for the addPerson function as practice.

I'm getting this error when I run the test:

1) SimpleStorage
       Should add a person when we call the function with the required params:
     TypeError: Cannot read properties of undefined (reading 'toString')
      at Context.<anonymous> (test/test-deploy.js:43:61)
      at processTicksAndRejections (node:internal/process/task_queues:96:5)
      at runNextTicks (node:internal/process/task_queues:65:3)
      at listOnTimeout (node:internal/timers:528:9)
      at processTimers (node:internal/timers:502:7)

This is the test I wrote:

    it("Should add a person when we call the function with the required params", async function () {
        const personName = "Harry";
        const favoriteNumber = "10";

        const transactionResponse = await simpleStorage.addPerson(
            personName,
            favoriteNumber
        );

        await transactionResponse.wait(1);

        const expectedFavoriteNumber = await simpleStorage.nameToFavoriteNumber[
            personName
        ];

        assert.equal(favoriteNumber, expectedFavoriteNumber.toString());
    });

This is the addPerson function in the SimpleStorage contract:

    function addPerson(string memory _name, uint256 _favoriteNumber) public {
        people.push(People(_favoriteNumber, _name));
        nameToFavoriteNumber[_name] = _favoriteNumber;
    }

Is there a specific way to access the mapping variable "nameToFavoriteNumber" using hardhat? Help would be appreciated. Thanks!

[RoboCrypter]

@musubbinomair : Your mapping code please!

[musubomair]

mapping(string => uint256) public nameToFavoriteNumber;

[RoboCrypter]

@musubbinomair After addPerson you are accessing your personName incorrectly

[RoboCrypter]

@musubbinomair : You should do it like this: after

const transactionResponse = await simpleStorage.addPerson(
            personName,
            favoriteNumber
        );

const peopleArray = await simpleStorage.people(0)
const favouriteNumber = peopleArray.favoriteNumber
const personName = peopleArray.name

[musubomair]

Ahhh, I see. Thank you! It worked.

[AakashMalik274]

@abossofmyself Hey I didn't understand what was he/I was doing wrong. Could you explain or share any resource please ?

[0xVenky]

Hey @AakashMalik274 Since addPerson is an array, you can either compare the values of the arrayat a particular index or you can compare each parameter in the array.

In the test, you can do this:

const expectedValue = [14, "Adam"]; const transactionResponse = await simpleStorage.addPerson("Adam", 14); await transactionResponse.wait(1);
and then compare the value at index 0

const currentValue = await simpleStorage.people(0); assert.equal(currentValue.toString(), expectedValue);