@nadeshikon/plugin-nextjs/test/e2e/next-test-lib/e2e-utils.ts

Run Next.js seamlessly on Netlify

import path from 'path'
import assert from 'assert'
import { NextConfig } from 'next'
import { InstallCommand, NextInstance, PackageJson } from './next-modes/base'
import { NextDeployInstance } from './next-modes/next-deploy'

// increase timeout to 5 minutes, because it includes the time to deploy the site
jest.setTimeout(5 * 60 * 1000)

const testsFolder = path.join(__dirname, '..')

let testFile
const testFileRegex = /\.test\.(js|tsx?)/

const visitedModules = new Set()
const checkParent = (mod) => {
  if (!mod?.parent || visitedModules.has(mod)) return
  testFile = mod.parent.filename || ''
  visitedModules.add(mod)

  if (!testFileRegex.test(testFile)) {
    checkParent(mod.parent)
  }
}
checkParent(module)

process.env.TEST_FILE_PATH = testFile
// We only test "deploy" on Netlify
process.env.NEXT_TEST_MODE = 'deploy'
let testMode = 'deploy'

if (!testFileRegex.test(testFile)) {
  throw new Error(`e2e-utils imported from non-test file ${testFile} (must end with .test.(js,ts,tsx)`)
}

const testFolderModes = ['e2e', 'development', 'production']

const testModeFromFile = testFolderModes.find((mode) => testFile.startsWith(path.join(testsFolder, mode)))

if (testModeFromFile === 'e2e') {
  const validE2EModes = ['dev', 'start', 'deploy']

  if (!process.env.NEXT_TEST_JOB && !testMode) {
    require('console').warn('Warn: no NEXT_TEST_MODE set, using default of start')
    testMode = 'start'
  }
  assert(
    validE2EModes.includes(testMode),
    `NEXT_TEST_MODE must be one of ${validE2EModes.join(', ')} for e2e tests but received ${testMode}`,
  )
} else if (testModeFromFile === 'development') {
  testMode = 'dev'
} else if (testModeFromFile === 'production') {
  testMode = 'start'
}

if (testMode === 'dev') {
  ;(global as any).isNextDev = true
} else if (testMode === 'deploy') {
  ;(global as any).isNextDeploy = true
} else {
  ;(global as any).isNextStart = true
}

if (!testMode) {
  throw new Error(`No 'NEXT_TEST_MODE' set in environment, this is required for e2e-utils`)
}
require('console').warn(`Using test mode: ${testMode} in test folder ${testModeFromFile}`)

/**
 * FileRef is wrapper around a file path that is meant be copied
 * to the location where the next instance is being created
 */
export class FileRef {
  public fsPath: string

  constructor(path: string) {
    this.fsPath = path
  }
}

let nextInstance: NextInstance | undefined = undefined

if (typeof afterAll === 'function') {
  afterAll(async () => {
    if (nextInstance) {
      await nextInstance.destroy()
      throw new Error(
        `next instance not destroyed before exiting, make sure to call .destroy() after the tests after finished`,
      )
    }
  })
}

/**
 * Sets up and manages a Next.js instance in the configured
 * test mode. The next instance will be isolated from the monorepo
 * to prevent relying on modules that shouldn't be
 */
export async function createNext(opts: {
  files:
    | FileRef
    | {
        [filename: string]: string | FileRef
      }
  dependencies?: {
    [name: string]: string
  }
  nextConfig?: NextConfig
  skipStart?: boolean
  installCommand?: InstallCommand
  buildCommand?: string
  packageJson?: PackageJson
  startCommand?: string
  packageLockPath?: string
  env?: Record<string, string>
}): Promise<NextInstance> {
  try {
    if (nextInstance) {
      throw new Error(`createNext called without destroying previous instance`)
    }

    nextInstance = new NextDeployInstance(opts)

    nextInstance.on('destroy', () => {
      nextInstance = undefined
    })

    await nextInstance.setup()

    return nextInstance!
  } catch (err) {
    require('console').error('Failed to create next instance', err)
    try {
      nextInstance.destroy()
    } catch (_) {}
    process.exit(1)
  }
}