Upgrading to v8 ​

This is the migration guide for upgrading from v7 to v8.

Since v8 has not yet been released, this is a work in progress list of any major and breaking changes in v8.

Breaking changes ​

Removed ability to change the locale on existing Faker instances ​

In order to facilitate better and easier locale fallback mechanics, we removed the methods to change the locales on existing Faker instances. Now, we expose specific faker instances for each locale that you can use:

Old

import { faker } from '@faker-js/faker';

faker.setLocale('de_CH');
// or
faker.locale = 'de_CH';
faker.fallbackLocale = 'en';

New

import { fakerDE_CH as faker } from '@faker-js/faker';

This also fixes issues where more than two locales are required:

Old

import { faker } from '@faker-js/faker';

const customFaker = new Faker({
  locale: 'de_CH', // the expected locale
  fallbackLocale: 'de', // ensure we have a German fallbacks for addresses
  locales: { de_CH, de, en },
});
const a = customFaker.internet.email();
customFaker.locale = 'en'; // neither 'de_CH' nor 'de' have emojis
const b = customFaker.internet.emoji();

New

import { Faker, de_CH, de, en, base } from '@faker-js/faker';

// same as fakerDE_CH
export const customFaker = new Faker({
  // Now multiple fallbacks are supported
  locale: [de_CH, de, en, base],
});
const a = customFaker.internet.email();
const b = customFaker.internet.emoji();

If you wish to create entries for multiple locales, you can still do so:

Old

import { faker } from '@faker-js/faker';

for (let user of users) {
  const lang = faker.helpers.arrayElement(['de', 'en', 'fr']);
  faker.locale = lang;
  user.email = faker.internet.email();
}

New

import { faker, fakerDE, fakerEN, fakerFR } from '@faker-js/faker';

for (let user of users) {
  const currentFaker = faker.helpers.arrayElement([fakerDE, fakerEN, fakerFR]);
  user.email = currentFaker.internet.email();
}

For more information refer to our Localization Guide.

faker.mersenne and faker.helpers.repeatString removed ​

faker.mersenne and faker.helpers.repeatString were only ever intended for internal use, and are no longer available.

Other deprecated methods removed/replaced ​

Locale renamed ​

The en_IND (English, India) locale was renamed to en_IN for consistency with other locales.

Deprecations and other changes ​

faker.name changed to faker.person ​

The whole faker.name module is now located at faker.person, as it contains more information than just names. The faker.name.* methods will continue to work as an alias in v8 and v9, but it is recommended to change to faker.person.*

faker.address changed to faker.location ​

The whole faker.address module is now located at faker.location, as it contains more information than just addresses. The faker.address.* methods will continue to work as an alias in v8 and v9, but it is recommended to change to faker.location.*

Number methods of faker.datatype moved to new faker.number module ​

The number-related methods previously found in faker.datatype have been moved to a new faker.number module. For the old faker.datatype.number method you should replace with faker.number.int or faker.number.float depending on the precision required.

By default, faker.number.float no longer defaults to a precision of 0.01

// OLD
faker.datatype.number({ max: 100 }); // 35
faker.datatype.number({ max: 100, precision: 0.01 }); // 35.21
faker.datatype.float({ max: 100 }); // 35.21
faker.datatype.float({ max: 100, precision: 0.001 }); // 35.211

// NEW
faker.number.int({ max: 100 }); // 35
faker.number.float({ max: 100 }); // 35.21092065742612
faker.number.float({ max: 100, precision: 0.01 }); // 35.21

Deprecation of faker.datatype.array ​

The method faker.datatype.array has been deprecated and will be removed in v9. If you need an array of useful values, you are better off creating your own one using faker.helpers.multiple.

allowLeadingZeros behavior change in faker.string.numeric ​

The allowLeadingZeros boolean parameter in faker.string.numeric (in the new string module) now defaults to true. faker.string.numeric will now generate numeric strings that could have leading zeros by default.

Simplified MIME type data ​

The functions faker.system.mimeType, faker.system.fileType and faker.system.fileExt now return data from a smaller set of more common MIME types, filetypes and extensions.