Cypress-selectors NPM

cypress-selectors

cypress-selectors is a library that provides a bunch of convenient declarative selectors for Cypress.

It helps to organize and re-use selectors and turns this:

const getSearchInput = () => cy.get('input');
const getSubmitSearchButton = () => cy.get('[cypress-id]=submit-search');
const getSearchResults = () => cy.get('.search-result');
const getMain = () => cy.xpath(`//div[@cypress-id='main']`)

into that:

class HomePage {
  @ByType('input') searchInput: Selector;
  @ByAttribute('submit-search') submitSearch: Selector;
  @ByClass('search-result') searchResults: Selector;
  @ByXPath(`//div[@cypress-id='main']`) main: Selector;
}

Installation

npm i -D cypress-selectors

Documentation

The docs are located at https://anton-kravchenko.github.io/cypress-selectors

Usage

Searching elements by attribute, class, id, type, selector, text, link text, name and xpath:

import { By } from 'cypress-selectors';
import type { Selector } from 'cypress-selectors';

class Selectors {
  @By.Id('main')
  static main: Selector; // equivalent of - cy.get('#main')

  @By.Type('input')
  static input: Selector; // equivalent of - cy.get('input')

  @By.Class('button')
  static button: Selector; // equivalent of - cy.get('.button')

  @By.Attribute('header')
  static header: Selector; // equivalent of - cy.get('[cypress-id=header')

  @By.Selector('ul > li .focus')
  static listItem: Selector; // equivalent of - cy.get('ul > li .focus')

  @By.XPath(`//input`)
  static xInput: Selector; // equivalent of - cy.xpath('//input')

  @By.Name('email')
  static email: Selector; // equivalent of - cy.get(`[name="email"]`)

  @By.Text.Exact('Foo')
  static bar: Selector; // equivalent of - cy.xpath(`//*[text()='Foo']`)

  @By.Text.Partial('Foo')
  static p: Selector; // equivalent of - cy.xpath(`/*[contains(text(), 'Foo')]`)

  @By.Link.ExactText('Link A')
  static linkA: Selector; // equivalent of - cy.xpath(`//a[text()='Link A']`)

  @By.Link.PartialText('Link B')
  static linkB: Selector; // equivalent of - cy.xpath(`//a[contains(text(), 'Link B')]`)
}

Searching child elements

2.1 By linking parent selector via reference

class Selectors {
  @ById('main') static parent: Selector;

  @ByClass('button', { parent: Selectors.parent })
  static children: Selector; // equivalent of - cy.get('#root .button')
}

2.2 By linking parent selector via alias and parentAlias attributes

class Selectors {
  @ById('main', { alias: 'root' })
  static parent: Selector;

  @ByClass('button', { parentAlias: 'root' })
  static children: Selector; // equivalent of - cy.get('#root .button')
}

Implementing Page Objects (PageObject is considered to be an anti-pattern although)

 class SearchPagePO {
   @ById('input') searchInput!: Selector;
   @ByAttribute('submit-search') submitSearch!: Selector;

   searchFor(term: string): SearchPagePO {
     this.searchInput.type(term);
     this.submitSearch.click();
     return this;
   }
 }

Searching by non-default attribute (by default ByAttribute uses cypress-id)

 class Selector {
   @ByAttribute('submit', { attribute: 'cy-data' })
   static customAttribute: Selector;
 }

Selecting elements by index

 class Selector {
   @ByAttribute('row', { eq: 0 }) static firstRow: Selector;
   @ByAttribute('row', { eq: 1 }) static secondRow: Selector;
 }

Selecting elements by XPath

 class Selector {
   @ByXPath(`//div[@cypress-id='app']/div[@cypress-id='children']`) static app: Selector;
   @ByXPath(`count(//div)`) static numberOfDivElements: Selector;
 }

Specifying custom timeout for selectors

 class Selectors {
   /* Will try to find an element for up to 10 seconds */
   @ById('main', { timeout: 10 * 1000 }) static parent: Selector;
   /* By default, timeout for any selector is inherited from "defaultCommandTimeout" value of Cypress configuration */
   @ById('app') static parent: Selector;
 }

Configuration

import { ResetSelectorsConfiguration, ConfigureSelectors } from 'cypress-selectors';

/* Setting configuration */
ConfigureSelectors({
  defaultAttribute: 'cy-id', // Default: 'cypress-id' - sets default attribute to be used by @ByAttribute selector
  isLoggingEnabled: true, // Default: false - logs generated selectors before accessing elements
  searchOnlyFirstLevelDescendants: true, /* Default: false
                                              => if true: the lib will be using `Child Selector` for resolving `child-parent` relationship - https://api.jquery.com/child-selector/
                                              => if false: the lib will be using `Descendant Selector` for resolving `child-parent` relationship - https://api.jquery.com/descendant-selector/ */
});

/* Re-setting configuration to defaults */
ResetSelectorsConfiguration();

Caveats

The library is built around decorators which are still a stage-2 proposal.
children-parent linking via alias and parentAlias works only within a single class - if you need to link selectors from different classes use children-parent linking via reference as shown in 2.2.
children-parent linking via reference uses static class fields stage-3 proposal. For some reason, babel-loader and ts-loader transpile code that defines static class fields differently.
For example, if you transpile the following code with babel-loader using @babel/preset-typescript preset and @babel/plugin-proposal-decorators, @babel/plugin-proposal-class-properties plugins:
```
class Selectors {
  @ById('main') static parent: Selector;
  @ByClass('button', { parent: Selectors.parent }) static children: Selector;
}
```
you will get cannot access 'parent' before initialization error, while if being transpiled via ts-loader it works as expected.
However, this example could be fixed by just extracting parent selector to a separate class as following:
```
class ParentSelectors {
  @ById('main') static parent: Selector;
}

class ChildrenSelectors {
  @ByClass('button', { parent: ParentSelectors.parent }) static children: Selector;
}
```
If child-parent linking is defined this way if will work with both babel-loader and ts-loader.
The documentation doesn't go into details on how to set up Cypress and transpiling via ts-loader. However, the setup of this project could be used as a good reference. The whole setup is done in 2 files: webpack.config.js and tsconfig.json. If you need another reference on setting up a project like this - check out this article.
All of the examples are declaring selectors as static class fields. This is not a requirement - the same functionality could be achieved with non static class fields. However please note, that child-parent relationship is not going to work without parent being declared as static class field.