LESSON 14 : Help with Unit Test - tokenURI

[DorianDaSilva]

  1) Dynamic SVG NFT Unit Tests
       mintNft
         emits an event and creates the NFT:
     Error: call revert exception; VM Exception while processing transaction: reverted with reason string "URI Query for nonexistent token" [ See: https://links.ethers.org/v5-errors-CALL_EXCEPTION ] (method="tokenURI(uint256)", data="0x08c379a00000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000001f55524920517565727920666f72206e6f6e6578697374656e7420746f6b656e00", errorArgs=["URI Query for nonexistent token"], errorName="Error", errorSignature="Error(string)", reason="URI Query for nonexistent token", code=CALL_EXCEPTION, version=abi/5.7.0)

======================================================================================

Unit test is returning this error when it reaches the following line in the "emits an event and creates the NFT" code block for describe("mintNft", function( ) { }

                 const tokenURI = await dynamicSvgNft.tokenURI(0)
                 assert.equal(tokenURI, highTokenUri)

======================================================================================

Full Code

          describe("mintNft", function () {
              it("emits an event and creates the NFT", async function () {
                console.log("ok")
                  const highValue = ethers.utils.parseEther("1") //1 dollar per ether
                  console.log("ok")
                  await expect(dynamicSvgNft.mintNft(highValue)).to.emit(
                      dynamicSvgNft,
                      "CreatedNFT"
                  )
                  const tokenCounter = await dynamicSvgNft.getTokenCounter()
                  assert.equal(tokenCounter.toString(), "1")
                  const tokenURI = await dynamicSvgNft.tokenURI(0)
                  assert.equal(tokenURI, highTokenUri)
              })

======================================================================================

Test also breaks & throws same error for
it("shifts the token uri to lower when the price doesn't surpass the highvalue", async function ( ) { }

                  const tokenURI = await dynamicSvgNft.tokenURI(0)
                  assert.equal(tokenURI, lowTokenUri)

======================================================================================

It seems tokenId is not available as per require statement in DynamicsvgNft.sol

    function tokenURI(uint256 tokenId) public view virtual override returns (string memory) {
        require(_exists(tokenId), "URI Query for nonexistent token");
        ....[CODE]...
}

======================================================================================

I tried importing tokenId as an argument for dynamicSvgNft.tokenURI(0) and a series of other attempts to include tokenId but all were unsuccesfull.

Any suggestions or ideas about what it is that I am missing in the test (Note: I am using the standard test from the repo that did require some adjustements for previous blocks)

Thank you!

[alymurtazamemon]

@DorianDaSilva Make sure you are incrementing the token counter after minting an NFT. Or just leave your repo link we will see it.

[DorianDaSilva]

@alymurtazamemon Done! Added hacktoberfest to the repo https://github.com/DorianDaSilva/UnitTestErrorFix-.git

[alymurtazamemon]

@DorianDaSilva Try @abossofmyself PRs and let me us know. Otherwise I will see that.

[DorianDaSilva]

@alymurtazamemon It works now. Turns out I was adding +1 to s_tokenCounter before emitting the mint hence the error. Also noticed that URL for the svg was wrong for some reason (not sure what happened tehre) but now all 14 tests pass perfectly.

Opened a new discussion about deploying ti on testnet bcz goerli alchemy url is returning an error (seems gerli is having issues)

Thank you for your ongoing help!

[alymurtazamemon]

@DorianDaSilva Yes, I identified the problem at first look, that is why told you to make a sure counter.

[DorianDaSilva]

@alymurtazamemon I didn't understand what was wrong with it then but now I do. So I don't make that same mistake again.

[RoboCrypter]

@DorianDaSilva : Send your repo link!

[RoboCrypter]

@DorianDaSilva : I have debugged your issue, And have made PRs, in your repo, Merge them, and try them out!

After Merging them, It should work just fine!

Let me know, If your issue gets resolved!

[DorianDaSilva]

@abossofmyself @alymurtazamemon

Below the link to the repo

https://github.com/DorianDaSilva/UnitTestErrorFix-.git

Thank you for your help as always.