Enforce valid titles (valid-title)

Checks that the title of Jest blocks are valid by ensuring that titles are:

• not empty,
• is a string,
• not prefixed with their block name,
• have no leading or trailing spaces

Rule Details

emptyTitle

An empty title is not informative, and serves little purpose.

Examples of incorrect code for this rule:

describe('', () => {});
describe('foo', () => {
  it('', () => {});
});
it('', () => {});
test('', () => {});
xdescribe('', () => {});
xit('', () => {});
xtest('', () => {});

Examples of correct code for this rule:

describe('foo', () => {});
describe('foo', () => {
  it('bar', () => {});
});
test('foo', () => {});
it('foo', () => {});
xdescribe('foo', () => {});
xit('foo', () => {});
xtest('foo', () => {});

titleMustBeString

Titles for test blocks should always be a string.

This is also applied to describe blocks by default, but can be turned off via the ignoreTypeOfDescribeName option:

Examples of incorrect code for this rule:

it(123, () => {});
describe(String(/.+/), () => {});
describe(myFunction, () => {});
xdescribe(myFunction, () => {});
describe(6, function () {});

Examples of correct code for this rule:

it('is a string', () => {});
test('is a string', () => {});
xtest('is a string', () => {});
describe('is a string', () => {});
describe.skip('is a string', () => {});
fdescribe('is a string', () => {});

Examples of correct code when ignoreTypeOfDescribeName is true:

it('is a string', () => {});
test('is a string', () => {});
xtest('is a string', () => {});
describe('is a string', () => {});
describe.skip('is a string', () => {});
fdescribe('is a string', () => {});

describe(String(/.+/), () => {});
describe(myFunction, () => {});
xdescribe(myFunction, () => {});
describe(6, function () {});

duplicatePrefix

A describe / test block should not start with duplicatePrefix

Examples of incorrect code for this rule

test('test foo', () => {});
it('it foo', () => {});

describe('foo', () => {
  test('test bar', () => {});
});

describe('describe foo', () => {
  test('bar', () => {});
});

Examples of correct code for this rule

test('foo', () => {});
it('foo', () => {});

describe('foo', () => {
  test('bar', () => {});
});

accidentalSpace

A describe / test block should not contain accidentalSpace

Examples of incorrect code for this rule

test(' foo', () => {});
it(' foo', () => {});

describe('foo', () => {
  test(' bar', () => {});
});

describe(' foo', () => {
  test('bar', () => {});
});

describe('foo  ', () => {
  test('bar', () => {});
});

Examples of correct code for this rule

test('foo', () => {});
it('foo', () => {});

describe('foo', () => {
  test('bar', () => {});
});

Options

interface Options {
  ignoreTypeOfDescribeName?: boolean;
  disallowedWords?: string[];
  mustNotMatch?: Partial<Record<'describe' | 'test' | 'it', string>> | string;
  mustMatch?: Partial<Record<'describe' | 'test' | 'it', string>> | string;
}

ignoreTypeOfDescribeName

Default: false

When enabled, the type of the first argument to describe blocks won't be checked.

disallowedWords

Default: []

A string array of words that are not allowed to be used in test titles. Matching is not case-sensitive, and looks for complete words:

Examples of incorrect code when using disallowedWords:

// with disallowedWords: ['correct', 'all', 'every', 'properly']
describe('the correct way to do things', () => {});
it('has ALL the things', () => {});
xdescribe('every single one of them', () => {});
test(`that the value is set properly`, () => {});

Examples of correct code when using disallowedWords:

// with disallowedWords: ['correct', 'all', 'every', 'properly']
it('correctly sets the value', () => {});
test('that everything is as it should be', () => {});
describe('the proper way to handle things', () => {});

mustMatch & mustNotMatch

Defaults: {}

Allows enforcing that titles must match or must not match a given Regular Expression. An object can be provided to apply different Regular Expressions to specific Jest test function groups (describe, test, and it).

Examples of incorrect code when using mustMatch:

// with mustMatch: '$that'
describe('the correct way to do things', () => {});
fit('this there!', () => {});

// with mustMatch: { test: '$that' }
describe('the tests that will be run', () => {});
test('the stuff works', () => {});
xtest('errors that are thrown have messages', () => {});

Examples of correct code when using mustMatch:

// with mustMatch: '$that'
describe('that thing that needs to be done', () => {});
fit('that this there!', () => {});

// with mustMatch: { test: '$that' }
describe('the tests that will be run', () => {});
test('that the stuff works', () => {});
xtest('that errors that thrown have messages', () => {});