cypress-map
Extra Cypress query commands for v12+
Install
Add this package as a dev dependency:
$ npm i -D cypress-map
# or using Yarn
$ yarn add -D cypress-map
Include this package in your spec or support file to use all custom query commands
import 'cypress-map'
Alternative: import only the query commands you need:
import 'cypress-map/commands/map'
import 'cypress-map/commands/tap'
API
apply
const double = (n) => n * 2
cy.wrap(100).apply(double).should('equal', 200)
It works like cy.then
but cy.apply(fn)
is a query command. Function fn
should be synchronous, pure function that only uses the subject argument and returns new value The function callback fn
cannot use any Cypress commands cy
.
You can pass additional left arguments to the callback function. Then it puts the subject as last argument before calling the function:
cy.wrap(8).apply(Cypress._.subtract, 4).should('equal', -4)
applyRight
Without arguments, cy.applyRight
works the same as cy.apply
. If you pass arguments, then the subject plus the arguments become the arguments to the callback. The subject is at the left (first) position
cy.wrap(8).applyRight(Cypress._.subtract, 4).should('equal', 4)
cy.wrap(8)
.apply((subject) => Cypress._.subtract(subject, 4))
.should('equal', 4)
partial
Sometimes you have the callback to apply, and you know the first argument(s), and just need to put the subject at the last position. This is where you can partially apply the known arguments to the given callback.
cy.wrap(100).partial(Cypress._.add, 5).should('equal', 105)
cy.wrap(100)
.apply((subject) => Cypress._.add(5, subject))
.should('equal', 105)
applyToFirst
If the current subject is an array, or a jQuery object, you can apply the given callback with arguments to the first item or element. The current subject will be the last argument.
cy.wrap(Cypress.$('<div>100</div><div>200</div>'))
.applyToFirst((base, el) => parseInt(el.innerText, base), 10)
.should('equal', 100)
applyToFirstRight
If the current subject is an array, or a jQuery object, you can apply the given callback with arguments to the first item or element. The current subject will be the first argument.
cy.wrap(Cypress.$('<div>100</div><div>200</div>'))
.applyToFirstRight((el, base) => parseInt(el.innerText, base), 10)
.should('equal', 100)
invokeFirst
We often just need to call a method on the first element / item in the current subject
cy.get(selector).invokeFirst('getBoundingClientRect')
map
Transforms every object in the given collection by running it through the given callback function. Can also map each object to its property. An object could be an array or a jQuery object.
cy.wrap(['10', '20', '30']).map(Number)
cy.get('.matching')
.map('innerText')
.should('deep.equal', ['first', 'third', 'fourth'])
You can even map properties of an object by listing callbacks. For example, let's convert the age
property from a string to a number
cy.wrap({
age: '42',
lucky: true,
})
.map({
age: Number,
})
.should('deep.equal', {
age: 42,
lucky: true,
})
You can avoid any conversion to simply pick the list of properties from an object
const person = {
name: 'Joe',
age: 21,
occupation: 'student',
}
cy.wrap(person).map(['name', 'age']).should('deep.equal', {
name: 'Joe',
age: 21,
})
You can extract nested paths by using "." in your property path
cy.wrap(people)
.map('name.first')
.should('deep.equal', ['Joe', 'Anna'])
cy.wrap(people)
.map('name')
.map('first')
.should('deep.equal', ['Joe', 'Anna'])
mapInvoke
cy.get('#items li')
.find('.price')
.map('innerText')
.mapInvoke('replace', '$', '')
.mapInvoke('trim')
reduce
cy.get('#items li')
.find('.price')
.map('innerText')
.mapInvoke('replace', '$', '')
.map(parseFloat)
.reduce((max, n) => (n > max ? n : max))
You can provide the initial accumulator value
cy.wrap([1, 2, 3])
.reduce((sum, n) => sum + n, 10)
.should('equal', 16)
See reduce.cy.js
tap
cy.get('#items li')
.find('.price')
.map('innerText')
.tap()
.mapInvoke('replace', '$', '')
.mapInvoke('trim')
.tap(console.info, 'trimmed strings')
Notice: if the label is provided, the callback function is called with label and the subject.
make
A retryable query that calls the given constructor function using the new
keyword and the current subject as argument.
cy.wrap('Jan 1, 2019')
.make(Date)
.invoke('getFullYear')
.should('equal', 2019)
print
A better cy.log
: yields the value, intelligently stringifies values using %
and string-format notation.
cy.wrap(42)
.print()
.should('equal', 42)
cy.wrap(42).print('the answer is %d')
cy.wrap({ name: 'Joe' }).print('person %o')
cy.wrap({ name: 'Joe' }).print('person name {0.name}')
cy.wrap(arr).print('array length {0.length}')
cy.wrap(arr).print((a) => `array with ${a.length} items`)
cy.wrap(arr).print((list) => list[2])
See print.cy.js for more examples
findOne
Finds a single item in the subject. Assumes subject is an array or a jQuery object. Uses Lodash _.find
method.
const isThree = n => n === 3
cy.wrap([...]).findOne(isThree).should('equal', 3)
cy.wrap([...]).findOne({ name: 'Anna' }).should('have.property', 'name', 'Anna')
See find-one.cy.js
primo
cy.get('.matching')
.map('innerText')
.primo()
.invoke('toUpperCase')
.should('equal', 'FIRST')
See primo.cy.js
prop
Works like cy.its
for objects, but gets the property for jQuery objects, which cy.its
does not
cy.get('#items li.matching')
.last()
.prop('ariaLabel')
.should('equal', 'four')
See prop.cy.js
update
Changes a single property inside the subject by running it through the given callback function. Useful to do type conversions, for example, let's convert the "age" property to a Number
cy.wrap({ age: '20' })
.update('age', Number)
.should('deep.equal', { age: 20 })
at
Returns a DOM element from jQuery object at position k
. Returns an item from array at position k
. For negative index, counts the items from the end.
cy.get('#items li').at(-1).its('innerText').should('equal', 'fifth')
See at.cy.js
sample
Returns a randomly picked item or element from the current subject
cy.get('#items li').sample().should('have.text', 'four')
If you pass a positive number, then it picks multiple elements or items
cy.get('#items li').sample(3).should('have.length', 3)
See sample.cy.js
second
Yields the second element from the current subject. Could be an element or an array item.
cy.get('#items li').second().should('have.text', 'second')
See second.cy.js
third
Yields the third element from the current subject. Could be an element or an array item.
cy.get('#items li').third().should('have.text', 'third')
See third.cy.js
asEnv
Saves current subject in Cypress.env
object. Note: Cypress.env object is reset before the spec run, but the changed values are passed from test to test. Thus you can easily pass a value from the first test to the second.
it('saves value in this test', () => {
cy.wrap('hello, world').asEnv('greeting')
})
it('saved value is available in this test', () => {
expect(Cypress.env('greeting'), 'greeting').to.equal('hello, world')
})
Do you really want to make the tests dependent on each other?
getInOrder
Queries the page using multiple selectors and returns the found elements in the specified order, no matter how they are ordered in the document. Retries if any of the selectors are not found.
cy.getInOrder('selector1', 'selector2', 'selector3', ...)
You can also use a single array of selector strings
cy.getInOrder(['h1', 'h2', 'h3'])
Supports parent subject
cy.get('...').getInOrder('...', '...')
stable
Sometimes you just want to wait until the element is stable. For example, if the element's text content does not change for N milliseconds, then we can consider the element to be text
stable.
cy.get('#message').stable('text')
Supported types: text
, value
(for input elements), css
, and element
(compares the element reference)
You can control the quiet period (milliseconds), and pass the log
and the timeout
options
cy.get('#message').stable('text', 500, { log: false, timeout: 6_000 })
When checking the CSS property to be stable, provide the name of the property:
cy.get('#message')
.stable('css', 'background-color', 100)
.should('have.css', 'background-color', 'rgb(255, 0, 0)')
See stable.cy.js and stable-css.cy.js
detaches
experimental
Retries until the element with the given selector detaches from DOM.
cy.contains('Click to re-render').click()
cy.detaches('#list')
Sometimes the detachment can happen right with the action and the cy.detaches(selector)
is too late. If you know the detachment might have already happened, you need to prepare for it by using an alias stored in the Cypress.env
object:
cy.get('#name2').asEnv('name')
cy.contains('Click to remove Joe').click()
cy.detaches('@name')
The jQuery object will be stored inside the Cypress.env
under the name
property.
See detach.cy.js
difference
Computes an object/arrays of the difference with the current subject object/array.
cy.wrap({ name: 'Joe', age: 20 })
.difference({ name: 'Joe', age: 30 })
.should('deep.equal', { age: { actual: 20, expected: 30 } })
You can use synchronous predicate functions to validate properties
.difference({ name: 'Joe', age: (n) => n > 15 })
Reports missing and extra properties. See difference.cy.js
Note: use have.length
to validate the number of items in an array:
.difference([Cypress._.object, Cypress._.object, Cypress._.object])
.should('have.length', 3)
You can check each item in the array subject using values / predicates from the expected object.
cy.wrap(people)
.difference({
name: Cypress._.isString,
age: (age) => age > 1 && age < 100,
})
.should('be.empty')
table
📝 to learn more about cy.table
command, read the blog post Test HTML Tables Using cy.table Query Command.
Extracts all cells from the current subject table. Yields a 2D array of strings.
cy.get('table').table()
You can slice the table to yield just a region .table(x, y, w, h)
For example, you can get 2 by 2 subregion
cy.get('table')
.table(0, 2, 2, 2)
.should('deep.equal', [
['Cary', '30'],
['Joe', '28'],
])
See the spec table.cy.js for more examples.
Tip: you can combine cy.table
with cy.map
, cy.mapInvoke
to get the parts of the table. For example, the same 2x2 part of the table could be extracted with:
cy.get('table')
.table()
.invoke('slice', 2, 4)
.mapInvoke('slice', 0, 2)
.should('deep.equal', [
['Cary', '30'],
['Joe', '28'],
])
Tip 2: to get just the headings row, combine .table
and .its
queries
cy.get('table')
.table(0, 0, 3, 1)
.its(0)
.should('deep.equal', ['Name', 'Age', 'Date (YYYY-MM-DD)'])
To get the last row, you could do:
cy.get('table').table().invoke('slice', -1).its(0)
To get the first column joined into a single array (instead of array of 1x1 arrays)
cy.get('table')
.table(0, 1, 1)
.invoke('flatMap', Cypress._.identity)
.should('deep.equal', ['Dave', 'Cary', 'Joe', 'Anna'])
toPlainObject
A query to convert special DOM objects into plain objects. For example, to convert DOMStringMap
instance into a plain object compatible with deep.equal
assertion we can do
cy.get('article')
.should('have.prop', 'dataset')
.toPlainObject()
.should('deep.equal', {
columns: '3',
indexNumber: '12314',
parent: 'cars',
})
By default uses JSON stringify and parse back. If you want to convert using entries
and fromEntries
, add an argument:
cy.wrap(new URLSearchParams(searchParams)).toPlainObject('entries')
invokeOnce
In Cypress v12 cy.invoke
became a query, which made working with asynchronous methods really unwieldy. The cy.invokeOnce
is a return the old way of calling the method and yielding the resolved value.
cy.wrap(app)
.invokeOnce('fetchName')
.should('equal', 'My App')
See the spec invoke-once.cy.js for more examples.
read
Assertion
Checks the exact text match or regular expression for a single element or multiple ones
cy.get('#name').should('read', 'Joe Smith')
cy.get('#ages').should('read', ['20', '35', '15'])
cy.get('#name').map('innerText').should('deep.equal', ['Joe Smith'])
cy.get('#ages')
.map('innerText')
.should('deep.equal', ['20', '35', '15'])
Using with regular expression or a mix of strings and regular expressions
cy.get('#name').should('read', /\sSmith$/)
cy.get('#ages').should('read', [/^\d+$/, '35', '15'])
cy.invoke vs cy.map vs cy.mapInvoke
Here are a few examples to clarify the different between the cy.invoke
, cy.map
, and cy.mapInvoke
query commands, see diff.cy.js
const list = ['apples', 'plums', 'bananas']
cy.wrap(list)
.invoke('sort')
.should('deep.equal', ['apples', 'bananas', 'plums'])
cy.wrap(list)
.mapInvoke('toUpperCase')
.should('deep.equal', ['APPLES', 'PLUMS', 'BANANAS'])
const reverse = (s) => s.split('').reverse().join('')
cy.wrap(list)
.map(reverse)
.should('deep.equal', ['selppa', 'smulp', 'sananab'])
.map('length')
.should('deep.equal', [6, 5, 7])
Misc
mapChain
I have added another useful command (not a query!) to this package. It allows you to process items in the array subject one by one via synchronous, asynchronous, or cy
command functions. This is because the common solution to fetch items using cy.each
, for example does not work:
cy.get(ids).each(id => cy.request('/users/' + id)).then(users => ...)
cy.get(ids).mapChain(id => cy.request('/users/' + id)).then(users => ...)
Types
This package includes TypeScript command definitions for its custom commands in the file commands/index.d.ts. To use it from your JavaScript specs:
If you are using TypeScript, include this module in your types list
{
"compilerOptions": {
"types": ["cypress", "cypress-map"]
}
}
The build process
The source code is in the src/commands folder. The build command produces ES5 code that goes into the commands
folder (should not be checked into the source code control). The package.json
in its NPM distribution includes commands
plus the types from src/commands/index.d.ts
file.
See also
- cypress-should-really has similar functional helpers for constructing the
should(callback)
function on the fly.
Note: this module does not have filter
method because Cypress API has query commands cy.filter and cy.invoke that you can use to filter elements in a jQuery object or items in an array. See the examples in the filter.cy.js spec. 📺 See video Filter Elements And Items With Retries.
Small print
Author: Gleb Bahmutov <gleb.bahmutov@gmail.com> © 2022
License: MIT - do anything with the code, but don't blame me if it does not work.
Support: if you find any problems with this module, email / tweet /
open issue on Github