@stackup/factory

Define factories to clean up fake data generation in tests

Usage no npm install needed!

<script type="module">
  import stackupFactory from 'https://cdn.skypack.dev/@stackup/factory';
</script>

README

@stackup/factory

Build Version Size License

Install

$ yarn add @stackup/factory --dev

Usage

First, you'll need to define a factory:

import { factory } from "@stackup/factory";

const UserFactory = factory({
  id: 1,
  name: "Rick",
});

Great, now to use that factory, just call the build method:

UserFactory.build();
// { id: 1, name: "Rick" }

You can override some of the properties, too:

UserFactory.build({ name: "Ray" });
// { id: 1, name: "Ray" }

Generate an array:

UserFactory.array(2).build();
// [
//   { id: 1, name: "Rick" },
//   { id: 1, name: "Rick" }
// ]

Your factories can reuse other factories:

const ProfileFactory = factory({
  user: UserFactory,
  friends: UserFactory.array(2),
});

ProfileFactory.build();
// {
//   user: { id: 1, name: "Rick" },
//   friends: [{ id: 1, name: "Rick" }, { id: 1, name: "Rick" }]
// }

Need something to be unique?

import { sequence } from "@stackup/factory";

const UserFactory = factory({
  email: sequence((n) => `${n}@example.com`),
});

UserFactory.build();
// { email: "78@example.com" }

UserFactory.build();
// { email: "79@example.com" }

Want random data?

import { random } from "@stackup/factory";

const UserFactory = factory({
  name: random((chance) => chance.name()),
});

UserFactory.build();
// { name: "Leona Floyd" }

UserFactory.build();
// { name: "Max Copeland" }

Fixtures

If you're snapshot testing, random data will break your tests. In that case, you can generate data deterministically:

UserFactory.fixture();
// { name: "Abe" }

UserFactory.fixture();
// { name: "Abe" }