Lesson 14 unit test random IPFS NFT

[SidharthK2]

it("reverts if payment amount is less than the mint fee", async function () {
                    const fee = await randomIpfsNft.getMintFee();
                    await expect(randomIpfsNft.requestNft({ value: mintFee.sub(ethers.utils.parseEther("0.001")) })
                    ).to.be.revertedWith("RandomIpfsNft__NeedMoreETHSent");

how are we calling the requestNft() function without passing a requestId?

link to unit test: https://github.com/PatrickAlphaC/hardhat-nft-fcc/blob/main/test/unit/randomIpfs.test.js

[alymurtazamemon]

@SidharthK2 We do not need that.

[SidharthK2]

Could you explain why?

[alymurtazamemon]

@SidharthK2 Where do you think we need that?

[SidharthK2]

for the mapping

[alymurtazamemon]

@SidharthK2 First of all for this test, we will not reach that part, before that it will revert to an error due to sending a low value. And the second thing, this id we take from random words request, we ask for one random word so the vrf will return as a 1 random number that we use as our id, above this code you can see.

[krakxn]

@SidharthK2

how are we calling the requestNft() function without passing a requestId?

You can certainly add it if it itches you, but it is redundant as it will not be used at all, and that is primarily the point of the sub-test.

Why will it be not used? Because in this subtest, we are checking for ""reverts if payment amount is less than the mint fee"", i.e. the amount of min. ETH must be greater than the mint fee else it should not proceed. To accomplish the task's purpose, we are passing a very miniscule amount of Ether, and consequently, the test passes as it leads to an error; the part with the requestId never really is evaluated and therefore, is not wrong syntactically and can be omitted (you can also include it, but since it will never be evaluated, it is pointless to do so, but you can definitely do so).