cypress-fail-on-console-error

/* cypress/support/e2e.ts or cypress/support/component.ts */ import failOnConsoleError, { Config } from 'cypress-fail-on-console-error'; const initialConfig: Config = { consoleMessages: [ 'You are using the development build of React.', /Ignored API call error/, // Example: Exclude specific errors from a third-party library /^TypeError: Cannot read properties of undefined \(reading 'property'\) from libX/, ], consoleTypes: ['error', 'warn'], // Fail on errors and warnings debug: false, }; // Initialize the plugin globally with initial configuration failOnConsoleError(initialConfig); // Optionally, expose commands to dynamically change config within tests const { getConfig, setConfig } = failOnConsoleError(initialConfig); Cypress.Commands.add('getConsoleErrorConfig', () => cy.wrap(getConfig())); Cypress.Commands.add('setConsoleErrorConfig', (newConfig: Partial<Config>) => cy.wrap(setConfig({ ...getConfig(), ...newConfig })) ); /* cypress/e2e/example.cy.ts */ interface CustomCommands { getConsoleErrorConfig: () => Cypress.Chainable<Config>; setConsoleErrorConfig: (config: Partial<Config>) => Cypress.Chainable<void>; } declare global { namespace Cypress { interface Chainable extends CustomCommands {} } } describe('Console Error Testing', () => { it('should pass if no console errors occur', () => { cy.visit('https://example.com'); // Test actions that should not produce console errors cy.contains('Example Domain').should('be.visible'); }); it('should fail if an unhandled console error occurs', () => { // Simulate an error on the page. This test is expected to fail. cy.visit('http://localhost:3000', { onBeforeLoad(win) { cy.stub(win.console, 'error').callsFake((message) => { // Log the error to Cypress command log but allow it to trigger the plugin cy.log(`App Console Error: ${message}`); // Do NOT call original `win.console.error` to avoid double logging or stack overflow }); }, }); cy.window().then((win) => { win.eval(`console.error('This is an intentional error for testing!');`); }); // The test will fail due to the console.error() call unless it's configured to be ignored. }); it('should ignore a specific console error message', () => { cy.setConsoleErrorConfig({ consoleMessages: ['Expected error message to ignore'], }); cy.visit('http://localhost:3000', { onBeforeLoad(win) { cy.stub(win.console, 'error').callsFake((message) => { cy.log(`App Console Error (stubbed): ${message}`); }); }, }); cy.window().then((win) => { win.eval(`console.error('Expected error message to ignore');`); }); // This test should pass because the error message is configured to be ignored. cy.contains('Example Domain').should('be.visible'); }); });