Multi-Extension Module Loader

Create a module loader utility that enables Node.js to require files with multi-dot extensions (e.g., .spec.js, .config.json, .test.ts).

Problem

Node.js's module system only recognizes the last extension in a filename. For example, with a file named config.production.json, Node.js only sees .json and doesn't recognize .production.json as a valid extension handler. This limitation prevents custom extension handlers from working with multi-dot filenames.

Your task is to implement a module loader that patches Node.js's module loading mechanism to support multi-dot extensions.

Requirements

Core Functionality

The loader must:

1. Register custom extension handlers for multi-dot extensions (e.g., .test.js, .config.json)
2. Correctly resolve and load files with multi-dot extensions when using require()
3. Check all possible extension combinations, starting from the longest to shortest
4. Fall back to Node.js's default behavior for single-dot extensions
5. Maintain compatibility with existing single-extension handlers

Behavior

• When requiring a file ./config.production.json, the loader should first check if .production.json has a registered handler, then check .json
• Extension handlers should receive the module and filename and be responsible for loading the module's content
• The loader should not break existing Node.js module loading functionality

Test Cases

• Registering and using a .test.js extension handler successfully loads a file named example.test.js @test
• When a file has multiple dot extensions, the loader tries the longest extension first, then progressively shorter ones @test
• Files with single-dot extensions continue to work with Node.js's default handlers @test
• Requiring a file with an unregistered multi-dot extension falls back to checking the shorter extension @test

Implementation

@generates

API

/**
 * Registers a custom handler for a multi-dot extension.
 *
 * @param {string} extension - The extension to register (e.g., '.test.js', '.config.json')
 * @param {function} handler - Function that takes (module, filename) and loads the content
 */
function registerExtension(extension, handler) {
  // IMPLEMENTATION HERE
}

/**
 * Patches Node.js's module system to support multi-dot extensions.
 * Must be called before requiring any files with multi-dot extensions.
 */
function patchModuleLoader() {
  // IMPLEMENTATION HERE
}

module.exports = {
  registerExtension,
  patchModuleLoader
};

Dependencies { .dependencies }

coffeescript { .dependency }

Provides CoffeeScript compilation and module loading capabilities.

@satisfied-by