Module Fu

A small library providing utility methods to manage modules, particularly loading and uncaching (removing from cache). Handy for unit testing where having freshly loaded modules is wanted.

Installation

npm install module-fu --save-dev

This example assumes you'll be using it in development only.

Example

  var mf = require('module-fu');
  mf.setResolver(function(moduleName) { return require.resolve(moduleName); });
  var expect = require('chai').expect;
 
  describe('my-cool-module', function() {	
    it('rocks because I reload the module.', function() {
    	var info = mf.find('./my-cool-module.js');
    	expect(info.length).to.equal(0);
 
    	var mcm = mf.load('./my-cool-module.js');
    	info = mf.find('./my-cool-module.js');
    	expect(info.length).to.equal(1);
    	expect(d1.hello()).to.equal('hello world');
 
    	mf.remove('./my-cool-module.js');
    	info = mf.find('./my-cool-module.js');
    	expect(info.length).to.equal(0);
    });
  });

Tests

npm test

API

setResolver(resolverFn)

Description

Sets the function used to resolve module references. Usually needs setting from where this module is loaded.

Parameters

• resolverFn - A function that performs the equivalent of require.resolve()

Example

  var mf = require('module-fu');
  mf.setResolver(function(moduleName) { return require.resolve(moduleName); });
  var mcm = mf.load('./my-cool-module.js');

remove(moduleName)

Description

Removes a module from the cache

Parameters

• moduleName - the name of the module to remove from the cache.

find(moduleName[, callback])

Description

Searches the cache for references to a module.

Parameters

• moduleName - the name of the module to search for.
• callback - optional callback. If specified it will be called for each occurrence found.

Returns

If no callback is specified => an array of results found. If a callback is specified => undefined.

load(moduleName[, importName])

Description

Loads a module and optionally retrieves an import. Designed to give nice messages when the module or import is not found so mistakes in writing tests are picked up quickly.

Parameters

• moduleName - the name of the module to load.
• importName - Optional name of the import to get and return for the module.

Returns

If an importName is specified => The module exported property with the same name. If no importName is specified => The module is returned.

reload(moduleName[, importName])

Description

Reloads a module and optionally retrieves an import. Similar to load but first removes the module from the cache.

Parameters

• moduleName - the name of the module to reload.
• importName - Optional name of the import to get and return for the module.

Returns

If an importName is specified => The module exported property with the same name. If no importName is specified => The module is returned.

Credits

Adapted from this answer to a StackOverflow question.