Announcing: bond 1.0.0

When switching from jasmine to mocha, I found myself missing jasmine spies. bond is my reproduction of jasmine spies (with a few enhancements) in a package that can be used with any testing framework.

bond: the simple stub/spy JavaScript library

I wanted to have something that did one thing and did it well. That thing is to stub/spy on JavaScript objects.

The name comes from a famous spy, but it also fits gramatically. You are bonding a reference to a value: bond(object, property).to(value).

Given that I’ve not changed bond in 7 months, I think it’s time to release bond@1.0.0. It works in browsers and Node.js (bondjs on npm).

bond api

You can checkout the full README for a breakdown of the api, but I wanted to call out the core concepts here.

The core method accepts an object and propertyName, returning the bond api.

bond(object, propertyName)

The bond api allows you to stub or spy on this property. For example, you could stub a method to return a specific value with bond(object, methodName).return(someValue). You can also stub a value property with bond(object, propertyName).to(someValue).

There are some cases where you want to spy on a method without changing it. For that, you can use bond(object, methodName).through().

bond spies

When you create a bond spy, you can check to see how many times it was called with spy.called. I abuse the fact that 0 is falsey when I use this method: if spy.called then ....

You can check that a spy was called with specific arguments as well: spy.calledWith(arg1, arg2, ...).


I have been using bond for about a year now. I find that it does exactly what I need.

You can even use it to write a quick require.cache stub for those cases where a module only exports a function and you can’t stub or spy on it.

stubModule = (modulePath, stub) ->
  resolvedPath = require.resolve(modulePath)
  require.cache[resolvedPath] = stub

Let me know how you like bond below!