test.js

const { MerkleTree } = require('merkletreejs')
const SHA256 = require('crypto-js/sha256')

let users = initializeUsers(256);

function addAddress(index, address) {
    users[index] = address;
}

function verifyProof(sorted, hex){
    const leaves = users.map(x => SHA256(x))
    let tree;
    if(sorted){
        tree = new MerkleTree(leaves, SHA256, {sortPairs: true})
    } else {
        tree = new MerkleTree(leaves, SHA256)
    }
    const root = tree.getRoot().toString('hex')
    const leaf = SHA256('hahaha')
    let proof;
    if(hex){
        proof = tree.getHexProof(leaf)
    } else {
        proof = tree.getProof(leaf)
    }

    console.log("Verified: ", tree.verify(proof, leaf, root))
}

function initializeUsers(length){
    let users = new Array(length)
    for(var i = 0; i < users.length; i++) users[i] = "0x0";
    return users;
}

addAddress(0, "hahaha")
console.log("Not sorted, not hex => works")
verifyProof(false, false)
console.log()
console.log("Sorted, Hex => works")
verifyProof(true, true)
console.log()
console.log("Sorted, not hex => Works")
verifyProof(true, false)
console.log()
console.log("Not sorted, Hex => Doesn't work")
verifyProof(false, true)