diffable-objects/dist/decorator.js

A package for dynamic state tracking for Cloudflare's Durable Objects using SQLite

import { state } from "./index.js";
import { unreachable } from "./util.js";
export function diffable() {
    // biome-ignore lint/style/noArguments: <explanation>
    const args = arguments;
    const fn = (opts = {}) => (_, { kind, name: fieldName }) => {
        if (kind === "field") {
            return function (initialValue) {
                const fieldNameNonPrivate = fieldName.replace(/^#/, "");
                return state(this.ctx, opts.name ?? fieldNameNonPrivate, initialValue, {
                    snapshotPolicy: opts.snapshotPolicy ?? { changes: 10 },
                });
            };
        }
        throw new Error("Only fields can be persistable");
    };
    if (args.length === 0) {
        return fn();
    }
    if (args.length === 1) {
        const [optsOrName] = args;
        if (typeof optsOrName === "object") {
            return fn(optsOrName);
        }
        return fn(optsOrName ? { name: optsOrName } : {});
    }
    const [value, metadata] = args;
    return fn()(value, metadata ?? unreachable());
}