[PluginEvents] Cypress fires the 'before:spec' event twice

[elaichenkov]

Current behavior

Cypress fires before:spec event twice.

npx cypress run
Missing baseUrl in compilerOptions. tsconfig-paths will be skipped

====================================================================================================

  (Run Starting)

  ┌────────────────────────────────────────────────────────────────────────────────────────────────┐
  │ Cypress:        12.9.0                                                                         │
  │ Browser:        Electron 106 (headless)                                                        │
  │ Node Version:   v16.15.0 (/Users/ylaichenkov/.nvm/versions/node/v16.15.0/bin/node)             │
  │ Specs:          1 found (todo.cy.js)                                                           │
  │ Searched:       cypress/e2e/**/*.cy.{js,jsx,ts,tsx}                                            │
  │ Experiments:    experimentalInteractiveRunEvents=true                                          │
  └────────────────────────────────────────────────────────────────────────────────────────────────┘


────────────────────────────────────────────────────────────────────────────────────────────────────

  Running:  todo.cy.js                                                                      (1 of 1)

--------> Running "before:spec" event <----------



  example to-do app

--------> Running "before:spec" event <----------

    ✓ displays two todo items by default (643ms)


  1 passing (3s)


  (Results)

Desired behavior

Cypress fires all events only once

Test code to reproduce

// example.cy.js

describe('example to-do app', () => {
  it('opens todo app', () => {
    cy.visit('https://example.cypress.io/todo')
  })
})

// cypress.config.js
const { defineConfig } = require('cypress')

module.exports = defineConfig({
  e2e: {
    setupNodeEvents(on, config) {
      on('before:spec', () => console.log('\n--------> Running "before:spec" event <----------\n'));
    },
  },
})

Cypress Version

12.9.0

Node version

v16.15.0

Operating System

macOS Version 13.2.1

Debug Logs

No response

Other

No response

[emilyrohrbough]

I was able to reproduce this behavior and this is not correct behavior. Thank you for the straight-forward reproduction. I actually noticed this same behavior this week.

Issue: The reason you are seeing it log 2x is without a baseUrl set and your first cy.visit() changes top, (or if you do have baseUrl set but your visit is to a different domain), Cypress is reloading on the page.

Expected Behavior: When Cypress is reloaded mid-test, it should not re-trigger the before:spec lifecycle event.

[mschile]

This appears to have been introduced in v10.8.0, possibly with this commit.

[badeball]

It is true that with v10.7.0, the before:spec isn't emitted twice, but task-handlers are. IE. the test is re-run for all practical purposes and non-idemponent task handlers must track state somehow. It also means that #26613 isn't strictly a duplicate of this..