Wait until the mining is done

Question

I'm trying to get a transaction once mining is done without a random timeout. I've checked similar questions but they aren't conclusive enough.

How do I get a transaction receipt once the mining is done?

Full code on Github.

try {
     ethereum
     .request({
      method: "eth_sendTransaction",
               params: [tx],
              })
             .then( 
              async (result) => 
              {
              let nftTxn = await nftContract.safeMint;
              console.log("Minting... please wait");
              const transactionReceipt = await web3.eth.getTransactionReceipt(result);
              await transactionReceipt.wait; //cannot await because of null
              if (transactionReceipt!=null) {
                console.log(`Mined... ${transactionReceipt}`);
              } else { console.log(`error`) }; //getting this
})

Answer 1

I think your question is partially answered here: How to wait until transaction is confirmed web3.js? This shows how to wait for a TX to be mined by periodically checking the output of getTransactionReceipt(...) untill it returns a value that is not null.

Also, I think there might be an issue with the following line:

let nftTxn = await nftContract.safeMint;

I think the method safeMint is not being called and is not making any transaction.