requirefire

A userland re-implementation of require for node.js. Useful in situations where you need a separate require cache and loader that can be intricately managed in tests.

Why

Sometimes you just have no other option -- and really, thats how this module should be used, as a backup to the backup plan. If you can, you should use plain old require. It supports many more things like require extensions, and is way more likely to just work for you.

That said, sometimes it is useful to have a cleanroom implementation of require that you know no other systems have messed with. Testing frameworks like jest mess with require without much opportunity to change how, so if you need to get around it, you can use requirefire for whatever you need finer control over the semantics of. Godspeed on your journey fellow modulonaut.

Installation

npm install requirefire

or

pnpm add requirefire

Usage

The requirefire module exports a factory function which must be called to create a new require function. So, import the createRequirefire function from the module, and then invoke it to create a new version of require.

import createRequirefire from "requirefire"

// create a requirefire instance
const requirefire = createRequirefire()

// require a module
const someModule = requirefire("./someModule")

// requiring the module a second time will return the same instance from a cache, same as normal `require`
someModule == requirefire("./someModule") // true

// requiring a module with requirefire will return a different instance of the same module than normal `require`
someModule == require("./someModule") // false

// the requirefire instance has a .cache property that can be mutated
delete requirefire.cache['path/to/someModule']

// once the cache is cleared, requirefire will re-execute the module from disk when required again
const newSomeModule = requirefire("./someModule")
someModule == newSomeModule // false

// multiple requirefire instances can be created, and each has an independent require cache
const otherRequirefire = createRequirefire()
requirefire("./someModule") == otherRequirefire("./someModule") // false

See Also

• rewire. requirefire is different in that it overrides transitive requires, caches modules for the same instance, can have multiple instances, and doesn't support monkeypatching
• proxyquire. requirefire is different in that it can have multiple instances, doesn't support monkeypatching, but doesn't need any explicit stubs for required modules

Credits

Most of this code is from the rewire module, but adjusted to work against a stateful instance with a require cache, and less oriented at monkeypatching. Thanks to Johannes for his hard work!