Can I reuse factory functions across different modules in a Bun plugin

Defining Individual Factory Functions

Start by creating separate factory functions for different functionalities or features you want to include in your plugin. For example:

javascript
// tsPluginFactory.js
export function tsPluginFactory(config) {
    return {
        name: "typescript-plugin",
        setup(build) {
            build.onLoad({ filter: /\.ts$/ }, async (args) => {
                const contents = await readFile(args.path); // Assume readFile is defined
                return { contents, loader: "ts" };
            });
        },
    };
}

javascript
// cssPluginFactory.js
export function cssPluginFactory(config) {
    return {
        name: "css-plugin",
        setup(build) {
            build.onLoad({ filter: /\.css$/ }, async (args) => {
                const contents = await readFile(args.path); // Assume readFile is defined
                return { contents, loader: "css" };
            });
        },
    };
}

Creating a Main Factory Function

Define a main factory function that calls these individual factory functions and combines their outputs into a single plugin object:

javascript
// combinedPluginFactory.js
import { tsPluginFactory } from "./tsPluginFactory.js";
import { cssPluginFactory } from "./cssPluginFactory.js";

export function combinedPluginFactory(config) {
    const tsPlugin = tsPluginFactory(config);
    const cssPlugin = cssPluginFactory(config);

    return {
        name: "combined-plugin",
        setup(build) {
            tsPlugin.setup(build);
            cssPlugin.setup(build);
        },
    };
}

Using the Combined Plugin

In your main Bun script, import and use the main factory function to create the plugin:

javascript
// index.js
import { plugin } from "bun";
import { combinedPluginFactory } from "./combinedPluginFactory.js";

const myCombinedPlugin = combinedPluginFactory({ /* config options */ });

Bun.build({
    entrypoints: ["./app.ts"],
    outdir: "./dist",
    plugins: [myCombinedPlugin],
});

By following this pattern, you can easily reuse factory functions across different modules within your Bun plugin, promoting code organization, reusability, and maintainability.