Implementation:Cypress io Cypress IsValidBrowser

Knowledge Sources	Cypress
Domains	Configuration, Validation
Last Updated	2026-02-12 00:00 GMT

Overview

Concrete tool for validating browser objects and configuration values provided by the @packages/config validation module.

Description

The validation module (packages/config/src/validation.ts) provides several validation functions: isValidBrowser checks individual browser object schema, isValidBrowserList validates the entire browser array, isValidClientCertificatesSet validates client certificate configurations, and resolveConfigValues (in project/utils.ts) resolves and validates the full configuration object.

Usage

Called during configuration resolution to validate user-provided browser lists, client certificates, and general configuration values before test execution begins.

Code Reference

Source Location

• Repository: cypress-io/cypress
• Files:
  • packages/config/src/validation.ts:L61-87 (isValidBrowser)
  • packages/config/src/validation.ts:L92-119 (isValidBrowserList)
  • packages/config/src/validation.ts:L324-369 (isValidClientCertificatesSet)
  • packages/config/src/project/utils.ts:L186-200 (resolveConfigValues)

Signature

export const isValidBrowser = (browser: any): ErrResult | true

export const isValidBrowserList = (
  _key: string,
  browsers: any
): ErrResult | true | string

export const isValidClientCertificatesSet = (
  _key: string,
  certsForUrls: any
): ErrResult | true | string

// From project/utils.ts
export function resolveConfigValues(
  config: Record<string, any>,
  defaults: Record<string, any>,
  resolved?: Record<string, any>
): Record<string, any>

Import

import { isValidBrowser, isValidBrowserList } from '@packages/config/src/validation'
import { resolveConfigValues } from '@packages/config/src/project/utils'

I/O Contract

Inputs

Name	Type	Required	Description
browser	object	Yes (isValidBrowser)	Browser object to validate
browsers	array	Yes (isValidBrowserList)	Array of browser objects
certsForUrls	array	Yes (isValidClientCertificatesSet)	Client certificate configurations
config	object	Yes (resolveConfigValues)	Full configuration object to resolve

Outputs

Name	Type	Description
true	boolean	Validation passed
ErrResult	{ key, value, type }	Validation error with details
string	string	Error message (for list validation)

Usage Examples

Validating a Browser Object

import { isValidBrowser } from '@packages/config/src/validation'

const result = isValidBrowser({
  name: 'chrome',
  family: 'chromium',
  displayName: 'Chrome',
  version: '120.0.6099.129',
  path: '/usr/bin/google-chrome',
  majorVersion: '120',
})

if (result === true) {
  console.log('Browser is valid')
} else {
  console.error(`Invalid ${result.key}: expected ${result.type}`)
}

Related Pages

Implements Principle

• Principle:Cypress_io_Cypress_Configuration_Validation

Requires Environment

• Environment:Cypress_io_Cypress_Browser_Requirements