Self-destruct the current module from require cache
require function for speed only evaluates each module once and stores
the result (whatever the module
exports) in the module cache. Sometimes this
causes problems, for example if you really need to re-evaluate the module again.
For example we might have a module that just reports if the environment variable is present
// is-foo.jsmoduleexports = StringprocessenvFOO
When testing this module, we might set
process.env.FOO before the first test and it works
But when we write another test it suddenly fails
// Error:// expect "test" to be "42"
foo still the first value? Let us enable just the second test - and it passes!
This is a pesky test failure because it depends on the order of tests, something Rocha can catch, but that is the point here.
The point is that module
./is-foo is executed only once in our tests. The second
require('./is-foo') the code inside (the single statement
module.exports = String(process.env.FOO)) is NOT evaluated. Instead the cached value
"test" is loaded and returned.
We can avoid caching value by switching
is-foo to return a function
// is-foomodule StringprocessenvFOO
and every client can just execute this function.
processenvFOO = 42const foo =// foo is now '42'
But we can also easily make the module
is-foo self-destruct from the
to force Node module system to reload an reevaluate its code. Just add a single line to
moduleexports = StringprocessenvFOO
Requires Node version 6 or above.
npm install --save unload-me
require('unload-me') at the end of the module you want to "self-destruct".
It will be re-evaluated next time someone requires it.
consoleconsolemoduleexports = 'foo'// require 'unload-me' to remove this module// from require.cache and force loading and// evaluating it again
See test/demo.js for full example
Author: Gleb Bahmutov <firstname.lastname@example.org> © 2017
License: MIT - do anything with the code, but don't blame me if it does not work.
Support: if you find any problems with this module, email / tweet / open issue on Github
Copyright (c) 2017 Gleb Bahmutov <email@example.com>
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
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