Extract the arguments provided in the constructor invocation

Question

Extract the arguments provided in the constructor invocation

Given

const anInstance = new Plugin({ a: 'path' })

Is it possible to retrieve the arguments passed to the instance?

anInstance./* some method */ === [{ a: 'path' }]

// or

someWrapper(anInstance) === [{ a: 'path' }]

Constraints:

You are not allowed to modify the internal workings of Plugin: consider it as an external dependency.
Plugin can accept multiple arguments of any type.
You cannot store the initial arguments in an external variable like this:
```
const config = { a: 'path' }
const anInstance = new Plugin(config)
```

Context: My goal is to test a webpack plugin configuration. For instance:

module.exports = {
  plugins: [
    new wepback.DllPlugin({
      name: '[name]',
      path: path.join(buildDir, '[name].json'),
    })
  ]
}

I aim to verify the configuration provided to DllPlugin. The third restriction is in place to avoid exporting the configuration for each plugin solely for the purpose of testing.

If there's no straightforward way to accomplish my initial objective, I may have to resort to exporting those configurations as I currently see no alternative means of accessing them.

javascript unit-testing arguments

Answer 1

Answer №1

If you want to create a new class, you can do so by using the extend keyword.

function NewClass() {}

class ExtendedClass extends NewClass {
  constructor(...parameters) {
    super();
    this.parameters = parameters;
    for (let parameter of parameters) {
      console.log(parameter);
    }
  }
  getParameters() {
    return this.parameters;
  }
}

const instance = new ExtendedClass({ key: "value" });
console.log(instance instanceof NewClass, instance.getParameters());

Answer 2

If you want to create a new class, you can do so by using the extend keyword.

function NewClass() {}

class ExtendedClass extends NewClass {
  constructor(...parameters) {
    super();
    this.parameters = parameters;
    for (let parameter of parameters) {
      console.log(parameter);
    }
  }
  getParameters() {
    return this.parameters;
  }
}

const instance = new ExtendedClass({ key: "value" });
console.log(instance instanceof NewClass, instance.getParameters());

Extract the arguments provided in the constructor invocation

Answer №1

Similar questions

Removing an element with a specific class that was created with Javascript can be done by clicking outside the box

Error encountered during the prerendering process on Vercel's Next.js build

Guide to Implementing i18n-iso-countries Library in React

Troubleshooting: Why jQuery is Not Functioning Properly in Conjunction

Issue with Element's Response to JQuery Click Event

Command for Sniping with Discord.js

What is the method for determining the coordinate range in a three.js environment?

Using a function as a prop in Vue js to retrieve data from an API

Conceal the block quotes while substituting with a newline

Using Dynamic Jinja HTML to Select Elements Dynamically

Quick inquiry about referencing state variables in the render method in React Native

Requirements for using Angular JS and Node JS

Obtain the view property access while invoking render function as a callback

Vue.js: Efficiently handling multiple buttons within a Dropdown menu

Node.js causing excessive CPU usage due to repeated gettimeofday calls

Having difficulty retrieving cookie from fetch() response

Establishing the JavaScript time and time zone using data stored in an SQL database and the ASP.NET code-behind page

Is it possible to achieve a file upload in splinter using Python?

How come my script that is dependent on the viewport does not apply classes?

Searching through an array to isolate only image files