Are there well-solved patterns and practices for handling errors in Solidity?

Question

In the spirit of Are there well-solved and simple storage patterns for Solidity?...

Are there known, battle-tested practices for how to deal with errors in large Solidity codebases?

It's common in software engineering to have a clear collection of error names, codes and descriptions, usually implemented via enums. The only project I've seen which adheres to this rigorous take on error handling is Compound, but there must be more. Compound's codebase is big and interwoven with other finesses like formal verification scripts, so their's is not strictly the best implementation to refer to when answering this question.

Answer 1

Solidity v0.8.4 to the rescue!

// SPDX-License-Identifier: UNLICENSED
pragma solidity ^0.8.4;

error Unauthorized();

contract VendingMachine {
    address payable owner = payable(msg.sender);

    function withdraw() public {
        if (msg.sender != owner) {
            revert Unauthorized();
        }

        owner.transfer(address(this).balance);
    }
    // ...
}

Notice the new and shiny error statement on line 4. This is a game changer for Solidity - easier to work with, more gas efficient, and more elegant than revert reason strings.