What is Spy in Chai?

What is Spy in Chai?

This is an addon plugin for the chai assertion library. It provides the most basic function spy ability and tests. This library is primarily meant to serve as a starting point for anyone interested in developing chai plugins. If developing a module, you are welcome to use this as a starting point.

How do you spy on Sinon?

var spy = sinon. spy(myFunc); Wraps the function in a spy. You can pass this spy where the original function would otherwise be passed when you need to verify how the function is being used.

What does Sinon spy do?

The primary use for spies is to gather information about function calls. You can also use them to help verify things, such as whether a function was called or not. The function sinon. spy returns a Spy object, which can be called like a function, but also contains properties with information on any calls made to it.

What is Spy in JS?

Spy-js is a tool for debugging, tracing, and profiling JavaScript running on different platforms/browsers/devices as well as server-side Node. js applications. Spy-js recognizes source maps so you can trace applications with CoffeeScript and TypeScript code.

What is Proxyquire?

Proxyquire is used to proxy a required module in node js. Having said that, if we require any dependency into the given file, we can proxy that with a stub, and only test code for given file.

What is chai Nodejs?

Chai is a BDD / TDD assertion library for node and the browser that can be delightfully paired with any javascript testing framework. For more information or to download plugins, view the documentation.

What is Spy and stub?

Spies are known as partially mock objects. It means spy creates a partial object or a half dummy of the real object by stubbing or spying the real ones. In spying, the real object remains unchanged, and we just spy some specific methods of it.

What is Proxyquire in node JS?

‘Proxyquire’ proxies nodeJS require dependencies to be stubbed while writing your unit tests. It stubs your nodeJS require dependencies with your minimalistic module. Let’s take an example. You have a utilities module — utils. js and it exports a couple of helper functions ‘func1’ and ‘func2’.

How do you stub a function in Sinon?

Create a file called lib.js and add the following code :

1. module.
2. // app.js file const lib = require(‘./lib’) console.
3. # run the app.js file node app.js.
4. # installing sinon npm install –save-dev sinon.

What is Mocha JS testing?

Mocha is a feature-rich JavaScript test framework running on Node. js and in the browser, making asynchronous testing simple and fun. Mocha tests run serially, allowing for flexible and accurate reporting, while mapping uncaught exceptions to the correct test cases.