injectr

Finally, a solution to node.js dependency injection

Install it

npm install injectr. Boom.

Use it

var injectr = require('injectr');
var myScript = injectr('./lib/myScript.js', {
    fs : mockFs,
    crypto : mockCrypto
});

Now when you require('fs') or require('crypto') in myScript.js, what you get is mockFs or mockCrypto.

Treat injectr like require for your tests, with a second argument to pass in your mocks. The only thing to note is that paths are relative to the working directory, not to the file location as with require.

Context

injectr gives you access to the context of the injectr'd file via an optional third argument. Provide an object, and injectr will modify it as necessary and use that as the context.

var myScript = injectr('./lib/myScript.js', {}, {
    Date : mockDate,
    setTimeout : mockSetTimeout
});

As of version 0.4, injectr doesn't create a full node.js context for you to use. Instead, it isolates your script in its own sandbox, allowing you to include mocks of only the bits that your script needs.

CoffeeScript

injectr compiles any *.coffee files for you, so you can test your CoffeeScript too. The default settings can be changed by overwriting the injectr.onload function. It takes the filename and file contents as arguments, and returns the compiled script.

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