jest-dom
Custom jest matchers to test the state of the DOM
The problem
You want to use jest to write tests that assert various things about the
state of a DOM. As part of that goal, you want to avoid all the repetitive
patterns that arise in doing so. Checking for an element's attributes, its text
content, its css classes, you name it.
This solution
The @testing-library/jest-dom
library provides a set of custom jest matchers
that you can use to extend jest. These will make your tests more declarative,
clear to read and to maintain.
Table of Contents
Installation
This module is distributed via npm which is bundled with node and
should be installed as one of your project's devDependencies
:
npm install --save-dev @testing-library/jest-dom
or
for installation with yarn package manager.
yarn add --dev @testing-library/jest-dom
Note: We also recommend installing the jest-dom eslint plugin which provides
auto-fixable lint rules that prevent false positive tests and improve test
readability by ensuring you are using the right matchers in your tests. More
details can be found at
eslint-plugin-jest-dom.
Usage
Import @testing-library/jest-dom
once (for instance in your tests setup
file) and you're good to go:
import '@testing-library/jest-dom'
setupFilesAfterEnv: ['<rootDir>/jest-setup.js']
With TypeScript
If you're using TypeScript, make sure your setup file is a .ts
and not a .js
to include the necessary types.
You will also need to include your setup file in your tsconfig.json
if you
haven't already:
"include": [
...
"./jest-setup.ts"
],
Custom matchers
@testing-library/jest-dom
can work with any library or framework that returns
DOM elements from queries. The custom matcher examples below are written using
matchers from @testing-library
's suite of libraries (e.g. getByTestId
,
queryByTestId
, getByText
, etc.)
toBeDisabled
toBeDisabled()
This allows you to check whether an element is disabled from the user's
perspective. According to the specification, the following elements can be
disabled:
button
, input
, select
, textarea
, optgroup
, option
, fieldset
.
This custom matcher considers an element as disabled if the element is among the
types of elements that can be disabled (listed above), and the disabled
attribute is present. It will also consider the element as disabled if it's
inside a parent form element that supports being disabled and has the disabled
attribute present.
Examples
<button data-testid="button" type="submit" disabled>submit</button>
<fieldset disabled><input type="text" data-testid="input" /></fieldset>
<a href="..." disabled>link</a>
expect(getByTestId('button')).toBeDisabled()
expect(getByTestId('input')).toBeDisabled()
expect(getByText('link')).not.toBeDisabled()
This custom matcher does not take into account the presence or absence of the
aria-disabled
attribute. For more on why this is the case, check
#144.
toBeEnabled
toBeEnabled()
This allows you to check whether an element is not disabled from the user's
perspective.
It works like not.toBeDisabled()
. Use this matcher to avoid double negation in
your tests.
This custom matcher does not take into account the presence or absence of the
aria-disabled
attribute. For more on why this is the case, check
#144.
toBeEmptyDOMElement
toBeEmptyDOMElement()
This allows you to assert whether an element has no visible content for the
user. It ignores comments but will fail if the element contains white-space.
Examples
<span data-testid="not-empty"><span data-testid="empty"></span></span>
<span data-testid="with-whitespace"> </span>
<span data-testid="with-comment"></span>
expect(getByTestId('empty')).toBeEmptyDOMElement()
expect(getByTestId('not-empty')).not.toBeEmptyDOMElement()
expect(getByTestId('with-whitespace')).not.toBeEmptyDOMElement()
toBeInTheDocument
toBeInTheDocument()
This allows you to assert whether an element is present in the document or not.
Examples
<span data-testid="html-element"><span>Html Element</span></span>
<svg data-testid="svg-element"></svg>
expect(
getByTestId(document.documentElement, 'html-element'),
).toBeInTheDocument()
expect(getByTestId(document.documentElement, 'svg-element')).toBeInTheDocument()
expect(
queryByTestId(document.documentElement, 'does-not-exist'),
).not.toBeInTheDocument()
Note: This matcher does not find detached elements. The element must be added
to the document to be found by toBeInTheDocument. If you desire to search in a
detached element please use: toContainElement
toBeInvalid
toBeInvalid()
This allows you to check if an element, is currently invalid.
An element is invalid if it has an
aria-invalid
attribute
with no value or a value of "true"
, or if the result of
checkValidity()
is false
.
Examples
<input data-testid="no-aria-invalid" />
<input data-testid="aria-invalid" aria-invalid />
<input data-testid="aria-invalid-value" aria-invalid="true" />
<input data-testid="aria-invalid-false" aria-invalid="false" />
<form data-testid="valid-form">
<input />
</form>
<form data-testid="invalid-form">
<input required />
</form>
expect(getByTestId('no-aria-invalid')).not.toBeInvalid()
expect(getByTestId('aria-invalid')).toBeInvalid()
expect(getByTestId('aria-invalid-value')).toBeInvalid()
expect(getByTestId('aria-invalid-false')).not.toBeInvalid()
expect(getByTestId('valid-form')).not.toBeInvalid()
expect(getByTestId('invalid-form')).toBeInvalid()
toBeRequired
toBeRequired()
This allows you to check if a form element is currently required.
An element is required if it is having a required
or aria-required="true"
attribute.
Examples
<input data-testid="required-input" required />
<input data-testid="aria-required-input" aria-required="true" />
<input data-testid="conflicted-input" required aria-required="false" />
<input data-testid="aria-not-required-input" aria-required="false" />
<input data-testid="optional-input" />
<input data-testid="unsupported-type" type="image" required />
<select data-testid="select" required></select>
<textarea data-testid="textarea" required></textarea>
<div data-testid="supported-role" role="tree" required></div>
<div data-testid="supported-role-aria" role="tree" aria-required="true"></div>
expect(getByTestId('required-input')).toBeRequired()
expect(getByTestId('aria-required-input')).toBeRequired()
expect(getByTestId('conflicted-input')).toBeRequired()
expect(getByTestId('aria-not-required-input')).not.toBeRequired()
expect(getByTestId('optional-input')).not.toBeRequired()
expect(getByTestId('unsupported-type')).not.toBeRequired()
expect(getByTestId('select')).toBeRequired()
expect(getByTestId('textarea')).toBeRequired()
expect(getByTestId('supported-role')).not.toBeRequired()
expect(getByTestId('supported-role-aria')).toBeRequired()
toBeValid
toBeValid()
This allows you to check if the value of an element, is currently valid.
An element is valid if it has no
aria-invalid
attributes
or an attribute value of "false"
. The result of
checkValidity()
must also be true
if it's a form element.
Examples
<input data-testid="no-aria-invalid" />
<input data-testid="aria-invalid" aria-invalid />
<input data-testid="aria-invalid-value" aria-invalid="true" />
<input data-testid="aria-invalid-false" aria-invalid="false" />
<form data-testid="valid-form">
<input />
</form>
<form data-testid="invalid-form">
<input required />
</form>
expect(getByTestId('no-aria-invalid')).toBeValid()
expect(getByTestId('aria-invalid')).not.toBeValid()
expect(getByTestId('aria-invalid-value')).not.toBeValid()
expect(getByTestId('aria-invalid-false')).toBeValid()
expect(getByTestId('valid-form')).toBeValid()
expect(getByTestId('invalid-form')).not.toBeValid()
toBeVisible
toBeVisible()
This allows you to check if an element is currently visible to the user.
An element is visible if all the following conditions are met:
- it is present in the document
- it does not have its css property
display
set to none
- it does not have its css property
visibility
set to either hidden
or
collapse
- it does not have its css property
opacity
set to 0
- its parent element is also visible (and so on up to the top of the DOM tree)
- it does not have the
hidden
attribute - if
<details />
it has the open
attribute
Examples
<div data-testid="zero-opacity" style="opacity: 0">Zero Opacity Example</div>
<div data-testid="visibility-hidden" style="visibility: hidden">
Visibility Hidden Example
</div>
<div data-testid="display-none" style="display: none">Display None Example</div>
<div style="opacity: 0">
<span data-testid="hidden-parent">Hidden Parent Example</span>
</div>
<div data-testid="visible">Visible Example</div>
<div data-testid="hidden-attribute" hidden>Hidden Attribute Example</div>
expect(getByText('Zero Opacity Example')).not.toBeVisible()
expect(getByText('Visibility Hidden Example')).not.toBeVisible()
expect(getByText('Display None Example')).not.toBeVisible()
expect(getByText('Hidden Parent Example')).not.toBeVisible()
expect(getByText('Visible Example')).toBeVisible()
expect(getByText('Hidden Attribute Example')).not.toBeVisible()
toContainElement
toContainElement(element: HTMLElement | SVGElement | null)
This allows you to assert whether an element contains another element as a
descendant or not.
Examples
<span data-testid="ancestor"><span data-testid="descendant"></span></span>
const ancestor = getByTestId('ancestor')
const descendant = getByTestId('descendant')
const nonExistantElement = getByTestId('does-not-exist')
expect(ancestor).toContainElement(descendant)
expect(descendant).not.toContainElement(ancestor)
expect(ancestor).not.toContainElement(nonExistantElement)
toContainHTML
toContainHTML(htmlText: string)
Assert whether a string representing a HTML element is contained in another
element. The string should contain valid html, and not any incomplete html.
Examples
<span data-testid="parent"><span data-testid="child"></span></span>
expect(getByTestId('parent')).toContainHTML('<span data-testid="child"></span>')
expect(getByTestId('parent')).toContainHTML('<span data-testid="child" />')
expect(getByTestId('parent')).not.toContainHTML('<br />')
expect(getByTestId('parent')).toContainHTML('data-testid="child"')
expect(getByTestId('parent')).toContainHTML('data-testid')
expect(getByTestId('parent')).toContainHTML('</span>')
Chances are you probably do not need to use this matcher. We encourage testing
from the perspective of how the user perceives the app in a browser. That's
why testing against a specific DOM structure is not advised.
It could be useful in situations where the code being tested renders html that
was obtained from an external source, and you want to validate that that html
code was used as intended.
It should not be used to check DOM structure that you control. Please use
toContainElement
instead.
toHaveAccessibleDescription
toHaveAccessibleDescription(expectedAccessibleDescription?: string | RegExp)
This allows you to assert that an element has the expected
accessible description.
You can pass the exact string of the expected accessible description, or you can
make a partial match passing a regular expression, or by using
expect.stringContaining/expect.stringMatching.
Examples
<a
data-testid="link"
href="/"
aria-label="Home page"
title="A link to start over"
>Start</a
>
<a data-testid="extra-link" href="/about" aria-label="About page">About</a>
<img src="avatar.jpg" data-testid="avatar" alt="User profile pic" />
<img
src="logo.jpg"
data-testid="logo"
alt="Company logo"
aria-describedby="t1"
/>
<span id="t1" role="presentation">The logo of Our Company</span>
expect(getByTestId('link')).toHaveAccessibleDescription()
expect(getByTestId('link')).toHaveAccessibleDescription('A link to start over')
expect(getByTestId('link')).not.toHaveAccessibleDescription('Home page')
expect(getByTestId('extra-link')).not.toHaveAccessibleDescription()
expect(getByTestId('avatar')).not.toHaveAccessibleDescription()
expect(getByTestId('logo')).not.toHaveAccessibleDescription('Company logo')
expect(getByTestId('logo')).toHaveAccessibleDescription(
'The logo of Our Company',
)
toHaveAccessibleName
toHaveAccessibleName(expectedAccessibleName?: string | RegExp)
This allows you to assert that an element has the expected
accessible name. It is useful, for instance,
to assert that form elements and buttons are properly labelled.
You can pass the exact string of the expected accessible name, or you can make a
partial match passing a regular expression, or by using
expect.stringContaining/expect.stringMatching.
Examples
<img data-testid="img-alt" src="" alt="Test alt" />
<img data-testid="img-empty-alt" src="" alt="" />
<svg data-testid="svg-title"><title>Test title</title></svg>
<button data-testid="button-img-alt"><img src="" alt="Test" /></button>
<p><img data-testid="img-paragraph" src="" alt="" /> Test content</p>
<button data-testid="svg-button"><svg><title>Test</title></svg></p>
<div><svg data-testid="svg-without-title"></svg></div>
<input data-testid="input-title" title="test" />
expect(getByTestId('img-alt')).toHaveAccessibleName('Test alt')
expect(getByTestId('img-empty-alt')).not.toHaveAccessibleName()
expect(getByTestId('svg-title')).toHaveAccessibleName('Test title')
expect(getByTestId('button-img-alt')).toHaveAccessibleName()
expect(getByTestId('img-paragraph')).not.toHaveAccessibleName()
expect(getByTestId('svg-button')).toHaveAccessibleName()
expect(getByTestId('svg-without-title')).not.toHaveAccessibleName()
expect(getByTestId('input-title')).toHaveAccessibleName()
toHaveAttribute
toHaveAttribute(attr: string, value?: any)
This allows you to check whether the given element has an attribute or not. You
can also optionally check that the attribute has a specific expected value or
partial match using
expect.stringContaining/expect.stringMatching
Examples
<button data-testid="ok-button" type="submit" disabled>ok</button>
const button = getByTestId('ok-button')
expect(button).toHaveAttribute('disabled')
expect(button).toHaveAttribute('type', 'submit')
expect(button).not.toHaveAttribute('type', 'button')
expect(button).toHaveAttribute('type', expect.stringContaining('sub'))
expect(button).toHaveAttribute('type', expect.not.stringContaining('but'))
toHaveClass
toHaveClass(...classNames: string[], options?: {exact: boolean})
This allows you to check whether the given element has certain classes within
its class
attribute.
You must provide at least one class, unless you are asserting that an element
does not have any classes.
Examples
<button data-testid="delete-button" class="btn extra btn-danger">
Delete item
</button>
<button data-testid="no-classes">No Classes</button>
const deleteButton = getByTestId('delete-button')
const noClasses = getByTestId('no-classes')
expect(deleteButton).toHaveClass('extra')
expect(deleteButton).toHaveClass('btn-danger btn')
expect(deleteButton).toHaveClass('btn-danger', 'btn')
expect(deleteButton).not.toHaveClass('btn-link')
expect(deleteButton).toHaveClass('btn-danger extra btn', {exact: true})
expect(deleteButton).not.toHaveClass('btn-danger extra', {exact: true})
expect(noClasses).not.toHaveClass()
toHaveFocus
toHaveFocus()
This allows you to assert whether an element has focus or not.
Examples
<div><input type="text" data-testid="element-to-focus" /></div>
const input = getByTestId('element-to-focus')
input.focus()
expect(input).toHaveFocus()
input.blur()
expect(input).not.toHaveFocus()
toHaveFormValues
toHaveFormValues(expectedValues: {
[name: string]: any
})
This allows you to check if a form or fieldset contains form controls for each
given name, and having the specified value.
It is important to stress that this matcher can only be invoked on a form
or a fieldset element.
This allows it to take advantage of the .elements property in form
and
fieldset
to reliably fetch all form controls within them.
This also avoids the possibility that users provide a container that contains
more than one form
, thereby intermixing form controls that are not related,
and could even conflict with one another.
This matcher abstracts away the particularities with which a form control value
is obtained depending on the type of form control. For instance, <input>
elements have a value
attribute, but <select>
elements do not. Here's a list
of all cases covered:
<input type="number">
elements return the value as a number, instead of
a string.<input type="checkbox">
elements:
- if there's a single one with the given
name
attribute, it is treated as a
boolean, returning true
if the checkbox is checked, false
if
unchecked. - if there's more than one checkbox with the same
name
attribute, they are
all treated collectively as a single form control, which returns the value
as an array containing all the values of the selected checkboxes in the
collection.
<input type="radio">
elements are all grouped by the name
attribute, and
such a group treated as a single form control. This form control returns the
value as a string corresponding to the value
attribute of the selected
radio button within the group.<input type="text">
elements return the value as a string. This also
applies to <input>
elements having any other possible type
attribute
that's not explicitly covered in different rules above (e.g. search
,
email
, date
, password
, hidden
, etc.)<select>
elements without the multiple
attribute return the value as a
string corresponding to the value
attribute of the selected option
, or
undefined
if there's no selected option.<select multiple>
elements return the value as an array containing all
the values of the selected options.<textarea>
elements return their value as a string. The value
corresponds to their node content.
The above rules make it easy, for instance, to switch from using a single select
control to using a group of radio buttons. Or to switch from a multi select
control, to using a group of checkboxes. The resulting set of form values used
by this matcher to compare against would be the same.
Examples
<form data-testid="login-form">
<input type="text" name="username" value="jane.doe" />
<input type="password" name="password" value="12345678" />
<input type="checkbox" name="rememberMe" checked />
<button type="submit">Sign in</button>
</form>
expect(getByTestId('login-form')).toHaveFormValues({
username: 'jane.doe',
rememberMe: true,
})
toHaveStyle
toHaveStyle(css: string | object)
This allows you to check if a certain element has some specific css properties
with specific values applied. It matches only if the element has all the
expected properties applied, not just some of them.
Examples
<button
data-testid="delete-button"
style="display: none; background-color: red"
>
Delete item
</button>
const button = getByTestId('delete-button')
expect(button).toHaveStyle('display: none')
expect(button).toHaveStyle({display: 'none'})
expect(button).toHaveStyle(`
background-color: red;
display: none;
`)
expect(button).toHaveStyle({
backgroundColor: 'red',
display: 'none',
})
expect(button).not.toHaveStyle(`
background-color: blue;
display: none;
`)
expect(button).not.toHaveStyle({
backgroundColor: 'blue',
display: 'none',
})
This also works with rules that are applied to the element via a class name for
which some rules are defined in a stylesheet currently active in the document.
The usual rules of css precedence apply.
toHaveTextContent
toHaveTextContent(text: string | RegExp, options?: {normalizeWhitespace: boolean})
This allows you to check whether the given node has a text content or not. This
supports elements, but also text nodes and fragments.
When a string
argument is passed through, it will perform a partial
case-sensitive match to the node content.
To perform a case-insensitive match, you can use a RegExp
with the /i
modifier.
If you want to match the whole content, you can use a RegExp
to do it.
Examples
<span data-testid="text-content">Text Content</span>
const element = getByTestId('text-content')
expect(element).toHaveTextContent('Content')
expect(element).toHaveTextContent(/^Text Content$/)
expect(element).toHaveTextContent(/content$/i)
expect(element).not.toHaveTextContent('content')
toHaveValue
toHaveValue(value: string | string[] | number)
This allows you to check whether the given form element has the specified value.
It accepts <input>
, <select>
and <textarea>
elements with the exception of
<input type="checkbox">
and <input type="radio">
, which can be meaningfully
matched only using toBeChecked
or
toHaveFormValues
.
For all other form elements, the value is matched using the same algorithm as in
toHaveFormValues
does.
Examples
<input type="text" value="text" data-testid="input-text" />
<input type="number" value="5" data-testid="input-number" />
<input type="text" data-testid="input-empty" />
<select multiple data-testid="select-number">
<option value="first">First Value</option>
<option value="second" selected>Second Value</option>
<option value="third" selected>Third Value</option>
</select>
Using DOM Testing Library
const textInput = getByTestId('input-text')
const numberInput = getByTestId('input-number')
const emptyInput = getByTestId('input-empty')
const selectInput = getByTestId('select-number')
expect(textInput).toHaveValue('text')
expect(numberInput).toHaveValue(5)
expect(emptyInput).not.toHaveValue()
expect(selectInput).not.toHaveValue(['second', 'third'])
toHaveDisplayValue
toHaveDisplayValue(value: string | RegExp | (string|RegExp)[])
This allows you to check whether the given form element has the specified
displayed value (the one the end user will see). It accepts <input>
,
<select>
and <textarea>
elements with the exception of
<input type="checkbox">
and <input type="radio">
, which can be meaningfully
matched only using toBeChecked
or
toHaveFormValues
.
Examples
<label for="input-example">First name</label>
<input type="text" id="input-example" value="Luca" />
<label for="textarea-example">Description</label>
<textarea id="textarea-example">An example description here.</textarea>
<label for="single-select-example">Fruit</label>
<select id="single-select-example">
<option value="">Select a fruit...</option>
<option value="banana">Banana</option>
<option value="ananas">Ananas</option>
<option value="avocado">Avocado</option>
</select>
<label for="multiple-select-example">Fruits</label>
<select id="multiple-select-example" multiple>
<option value="">Select a fruit...</option>
<option value="banana" selected>Banana</option>
<option value="ananas">Ananas</option>
<option value="avocado" selected>Avocado</option>
</select>
Using DOM Testing Library
const input = screen.getByLabelText('First name')
const textarea = screen.getByLabelText('Description')
const selectSingle = screen.getByLabelText('Fruit')
const selectMultiple = screen.getByLabelText('Fruits')
expect(input).toHaveDisplayValue('Luca')
expect(input).toHaveDisplayValue(/Luc/)
expect(textarea).toHaveDisplayValue('An example description here.')
expect(textarea).toHaveDisplayValue(/example/)
expect(selectSingle).toHaveDisplayValue('Select a fruit...')
expect(selectSingle).toHaveDisplayValue(/Select/)
expect(selectMultiple).toHaveDisplayValue([/Avocado/, 'Banana'])
toBeChecked
toBeChecked()
This allows you to check whether the given element is checked. It accepts an
input
of type checkbox
or radio
and elements with a role
of checkbox
,
radio
or switch
with a valid aria-checked
attribute of "true"
or
"false"
.
Examples
<input type="checkbox" checked data-testid="input-checkbox-checked" />
<input type="checkbox" data-testid="input-checkbox-unchecked" />
<div role="checkbox" aria-checked="true" data-testid="aria-checkbox-checked" />
<div
role="checkbox"
aria-checked="false"
data-testid="aria-checkbox-unchecked"
/>
<input type="radio" checked value="foo" data-testid="input-radio-checked" />
<input type="radio" value="foo" data-testid="input-radio-unchecked" />
<div role="radio" aria-checked="true" data-testid="aria-radio-checked" />
<div role="radio" aria-checked="false" data-testid="aria-radio-unchecked" />
<div role="switch" aria-checked="true" data-testid="aria-switch-checked" />
<div role="switch" aria-checked="false" data-testid="aria-switch-unchecked" />
const inputCheckboxChecked = getByTestId('input-checkbox-checked')
const inputCheckboxUnchecked = getByTestId('input-checkbox-unchecked')
const ariaCheckboxChecked = getByTestId('aria-checkbox-checked')
const ariaCheckboxUnchecked = getByTestId('aria-checkbox-unchecked')
expect(inputCheckboxChecked).toBeChecked()
expect(inputCheckboxUnchecked).not.toBeChecked()
expect(ariaCheckboxChecked).toBeChecked()
expect(ariaCheckboxUnchecked).not.toBeChecked()
const inputRadioChecked = getByTestId('input-radio-checked')
const inputRadioUnchecked = getByTestId('input-radio-unchecked')
const ariaRadioChecked = getByTestId('aria-radio-checked')
const ariaRadioUnchecked = getByTestId('aria-radio-unchecked')
expect(inputRadioChecked).toBeChecked()
expect(inputRadioUnchecked).not.toBeChecked()
expect(ariaRadioChecked).toBeChecked()
expect(ariaRadioUnchecked).not.toBeChecked()
const ariaSwitchChecked = getByTestId('aria-switch-checked')
const ariaSwitchUnchecked = getByTestId('aria-switch-unchecked')
expect(ariaSwitchChecked).toBeChecked()
expect(ariaSwitchUnchecked).not.toBeChecked()
toBePartiallyChecked
toBePartiallyChecked()
This allows you to check whether the given element is partially checked. It
accepts an input
of type checkbox
and elements with a role
of checkbox
with a aria-checked="mixed"
, or input
of type checkbox
with
indeterminate
set to true
Examples
<input type="checkbox" aria-checked="mixed" data-testid="aria-checkbox-mixed" />
<input type="checkbox" checked data-testid="input-checkbox-checked" />
<input type="checkbox" data-testid="input-checkbox-unchecked" />
<div role="checkbox" aria-checked="true" data-testid="aria-checkbox-checked" />
<div
role="checkbox"
aria-checked="false"
data-testid="aria-checkbox-unchecked"
/>
<input type="checkbox" data-testid="input-checkbox-indeterminate" />
const ariaCheckboxMixed = getByTestId('aria-checkbox-mixed')
const inputCheckboxChecked = getByTestId('input-checkbox-checked')
const inputCheckboxUnchecked = getByTestId('input-checkbox-unchecked')
const ariaCheckboxChecked = getByTestId('aria-checkbox-checked')
const ariaCheckboxUnchecked = getByTestId('aria-checkbox-unchecked')
const inputCheckboxIndeterminate = getByTestId('input-checkbox-indeterminate')
expect(ariaCheckboxMixed).toBePartiallyChecked()
expect(inputCheckboxChecked).not.toBePartiallyChecked()
expect(inputCheckboxUnchecked).not.toBePartiallyChecked()
expect(ariaCheckboxChecked).not.toBePartiallyChecked()
expect(ariaCheckboxUnchecked).not.toBePartiallyChecked()
inputCheckboxIndeterminate.indeterminate = true
expect(inputCheckboxIndeterminate).toBePartiallyChecked()
toHaveErrorMessage
toHaveErrorMessage(text: string | RegExp)
This allows you to check whether the given element has an
ARIA error message or not.
Use the aria-errormessage
attribute to reference another element that contains
custom error message text. Multiple ids is NOT allowed. Authors MUST use
aria-invalid
in conjunction with aria-errormessage
. Learn more from
aria-errormessage
spec.
Whitespace is normalized.
When a string
argument is passed through, it will perform a whole
case-sensitive match to the error message text.
To perform a case-insensitive match, you can use a RegExp
with the /i
modifier.
To perform a partial match, you can pass a RegExp
or use
expect.stringContaining("partial string")
.
Examples
<label for="startTime"> Please enter a start time for the meeting: </label>
<input
id="startTime"
type="text"
aria-errormessage="msgID"
aria-invalid="true"
value="11:30 PM"
/>
<span id="msgID" aria-live="assertive" style="visibility:visible">
Invalid time: the time must be between 9:00 AM and 5:00 PM
</span>
const timeInput = getByLabel('startTime')
expect(timeInput).toHaveErrorMessage(
'Invalid time: the time must be between 9:00 AM and 5:00 PM',
)
expect(timeInput).toHaveErrorMessage(/invalid time/i)
expect(timeInput).toHaveErrorMessage(expect.stringContaining('Invalid time'))
expect(timeInput).not.toHaveErrorMessage('Pikachu!')
Deprecated matchers
toBeEmpty
Note: This matcher is being deprecated due to a name clash with
jest-extended
. See more info in #216. In the future, please use only
toBeEmptyDOMElement
toBeEmpty()
This allows you to assert whether an element has content or not.
Examples
<span data-testid="not-empty"><span data-testid="empty"></span></span>
expect(getByTestId('empty')).toBeEmpty()
expect(getByTestId('not-empty')).not.toBeEmpty()
toBeInTheDOM
This custom matcher is deprecated. Prefer
toBeInTheDocument
instead.
toBeInTheDOM()
This allows you to check whether a value is a DOM element, or not.
Contrary to what its name implies, this matcher only checks that you passed to
it a valid DOM element. It does not have a clear definition of what "the DOM"
is. Therefore, it does not check whether that element is contained anywhere.
This is the main reason why this matcher is deprecated, and will be removed in
the next major release. You can follow the discussion around this decision in
more detail here.
As an alternative, you can use toBeInTheDocument
or
toContainElement
. Or if you just want to check if a value
is indeed an HTMLElement
you can always use some of
jest's built-in matchers:
expect(document.querySelector('.ok-button')).toBeInstanceOf(HTMLElement)
expect(document.querySelector('.cancel-button')).toBeTruthy()
Note: The differences between toBeInTheDOM
and toBeInTheDocument
are
significant. Replacing all uses of toBeInTheDOM
with toBeInTheDocument
will likely cause unintended consequences in your tests. Please make sure when
replacing toBeInTheDOM
to read through the documentation of the proposed
alternatives to see which use case works better for your needs.
toHaveDescription
This custom matcher is deprecated. Prefer
toHaveAccessibleDescription
instead, which
is more comprehensive in implementing the official spec.
toHaveDescription(text: string | RegExp)
This allows you to check whether the given element has a description or not.
An element gets its description via the
aria-describedby
attribute.
Set this to the id
of one or more other elements. These elements may be nested
inside, be outside, or a sibling of the passed in element.
Whitespace is normalized. Using multiple ids will
join the referenced elements’ text content separated by a space.
When a string
argument is passed through, it will perform a whole
case-sensitive match to the description text.
To perform a case-insensitive match, you can use a RegExp
with the /i
modifier.
To perform a partial match, you can pass a RegExp
or use
expect.stringContaining("partial string")
.
Examples
<button aria-label="Close" aria-describedby="description-close">
X
</button>
<div id="description-close">
Closing will discard any changes
</div>
<button>Delete</button>
const closeButton = getByRole('button', {name: 'Close'})
expect(closeButton).toHaveDescription('Closing will discard any changes')
expect(closeButton).toHaveDescription(/will discard/)
expect(closeButton).toHaveDescription(expect.stringContaining('will discard'))
expect(closeButton).toHaveDescription(/^closing/i)
expect(closeButton).not.toHaveDescription('Other description')
const deleteButton = getByRole('button', {name: 'Delete'})
expect(deleteButton).not.toHaveDescription()
expect(deleteButton).toHaveDescription('')
Inspiration
This whole library was extracted out of Kent C. Dodds' DOM Testing
Library, which was in turn extracted out of React Testing
Library.
The intention is to make this available to be used independently of these other
libraries, and also to make it more clear that these other libraries are
independent from jest, and can be used with other tests runners as well.
Other Solutions
I'm not aware of any, if you are please make a pull request and add it
here!
If you would like to further test the accessibility and validity of the DOM
consider jest-axe
. It doesn't
overlap with jest-dom
but can complement it for more in-depth accessibility
checking (eg: validating aria
attributes or ensuring unique id attributes).
Guiding Principles
The more your tests resemble the way your software is used, the more
confidence they can give you.
This library follows the same guiding principles as its mother library DOM
Testing Library. Go check them out
for more details.
Additionally, with respect to custom DOM matchers, this library aims to maintain
a minimal but useful set of them, while avoiding bloating itself with merely
convenient ones that can be easily achieved with other APIs. In general, the
overall criteria for what is considered a useful custom matcher to add to this
library, is that doing the equivalent assertion on our own makes the test code
more verbose, less clear in its intent, and/or harder to read.
Contributors
Thanks goes to these people (emoji key):
This project follows the all-contributors specification.
Contributions of any kind welcome!
LICENSE
MIT