doctest-js

Let your documentation be your testing suite.

Write JSDoc style doc examples on all your functions and then test them using doctest-js.

Contents

• Getting Started
  • 1. Install
  • 2. Write @example comments
  • 3. Run the tests
• Advanced
  • Multiple tests
  • Testing classes
• Usage online
• Contributing
• Credits
• Status

Getting Started

1. Install

npm install @supabase/doctest-js

2. Write @example comments

Create a JSDoc style @example on any functions that you want tested.

/**
 * Returns the sum of 2 numbers
 *
 * @example sum(1, 2)
 * //=> 3
 */
export const sum = (a, b) => {
  return a + b
}

Note that the expected return value must be prefixed by //=>.

3. Run the tests

Import the doctest function in your test suite and point it at the file.

import doctest from '@supabase/doctest-js';

describe('Doctests', () => {
  // file paths are relative to root of directory
  doctest('src/sum.js')
  doctest('src/someOtherFile.js')
})

Advanced

Multiple tests

You can run multiple tests for the same function.

/**
 * @example sum(1, 2)
 * //=> 3
 * @example sum(3, 4)
 * //=> 7
 */
export const sum = (a, b) => {
  return a + b
}

Testing classes

Testing classes requires you to pass a newed up instance of the class into the test itself. Here is a simple example:

// Arithmetic.js - a basic class which we need to test

class Arithmetic {
  constructor() {}

  /**
   * @example add(1, 2)
   * //=> 3
   */
  add(a, b) {
    return a + b
  }
}

export { Arithmetic }

// Arithmetic.test.js

const { Arithmetic } = require('./Arithmetic.js')

describe('passing doctest', () => {
  doctest('./Arithmetic.js', { instance: new Arithmetic() })
})

Usage online

See this in the wild:

• supabase/postgrest-js

Contributing

• Fork the repo on GitHub
• Clone the project to your own machine
• Commit changes to your own branch
• Push your work back up to your fork
• Submit a Pull request so that we can review your changes and merge

Credits

• Inspired by Elixir Doctests
• Original fork of mainshayne223/doctest-js. See issue #1.

Status

Ready for production! Watch and star this repo to keep updated on releases.

Sponsors

We are building the features of Firebase using enterprise-grade, open source products. We support existing communities wherever possible, and if the products don’t exist we build them and open source them ourselves. Thanks to these sponsors who are making the OSS ecosystem better for everyone.