[experimental] Create a sham of legacy @solana/web3.js that can be used as a drop-in replacement for most use cases

[steveluscher]

Motivation

You're an application that depends on a bunch of packages (mpl-token-metadata, @solana/wallet-adapter-react, etc.) and those packages themselves depend on @solana/web3.js (the legacy version).

Each of those packages use a tiny slice of web3.js. @solana/wallet-adapter-react for instance only does things like new PublicKey(), new Connection(), and publicKey.toBytes().

We could create a drop-in replacement for @solana/web3.js that only did the things that typical applications exercise; a sham, if you will.

This package would offer API compatible-ish versions of PublicKey, Connection et al, that used the new web3.js under the hood, or nothing at all.

Not a single line of your application should have to change and the legacy @solana/web3.js would just disappear from your bundle.

Example use case

#yolo replace all your legacy imports with that.

pnpm (package.json)

Using overrides.

"pnpm": {
  "overrides": {
    "@metaplex-foundation/mpl-token-metadata>@solana/web3.js": "npm:@solana/sham-web3.js"
  }
}

npm (package.json)

Using overrides.

"overrides": {
  "@metaplex-foundation/mpl-token-metadata": {
    "@solana/web3.js": "npm:@solana/sham-web3.js"
  }
}

Yarn (package.json)

Using resolutions.

"resolutions": {
  "@metaplex-foundation/mpl-token-metadata/@solana/web3.js": "npm:@solana/sham-web3.js"
}

Details

Here's an example of how you might implement a sham PublicKey.

import { getBase58Encoder } from '@solana/codecs-strings';

let memoizedBase58Encoder: ReturnType<typeof getBase58Encoder>;
function getMemoizedBase58Encoder() {
    if (!memoizedBase58Encoder) {
        memoizedBase58Encoder = getBase58Encoder();
    }
    return memoizedBase58Encoder;
}

class PublicKey {
    #address: string;
    constructor(address: string) {
        this.#address = address;
    }
    #getAddress() {
        return this.#address;
    }
    #getByteArray() {
        return getMemoizedBase58Encoder().encode(this.#address);
    }
    #getBuffer() {
        if (!__NODEJS__) {
            throw new Error('...');
        }
        return Buffer.from(this.#getByteArray());
    }
    encode = this.#getBuffer;
    equals(other: { toBase58: () => string }) {
        other.toBase58() === this.#address
    }
    toBase58 = this.#getAddress
    toBuffer = this.#getBuffer
    toBytes = this.#getByteArray
    toJSON = this.#getAddress
    toString = this.#getAddress
    get [Symbol.toStringTag]() {
        return `PublicKeyCompat(${this.#address})`;
    }
}

Playground link.