next.js/test/e2e/app-dir/app-validation/validation.test.ts

import { nextTestSetup } from 'e2e-utils'
import { computeCacheBustingSearchParam } from 'next/dist/shared/lib/router/utils/cache-busting-search-param'

describe('app dir - validation', () => {
  const { next, skipped } = nextTestSetup({
    files: __dirname,
    skipDeployment: true,
  })

  if (skipped) {
    return
  }

  it('should error when passing invalid router state tree', async () => {
    const stateTree1 = JSON.stringify(['', ''])
    const stateTree2 = JSON.stringify(['', {}])

    const headers1 = {
      RSC: '1',
      'Next-Router-State-Tree': stateTree1,
    }

    const headers2 = {
      RSC: '1',
      'Next-Router-State-Tree': stateTree2,
    }

    const url1 = new URL('/', 'http://localhost')
    const url2 = new URL('/', 'http://localhost')

    // Add cache busting search param for both requests
    const cacheBustingParam1 = computeCacheBustingSearchParam(
      undefined,
      undefined,
      stateTree1,
      undefined
    )
    const cacheBustingParam2 = computeCacheBustingSearchParam(
      undefined,
      undefined,
      stateTree2,
      undefined
    )

    if (cacheBustingParam1) {
      url1.searchParams.set('_rsc', cacheBustingParam1)
    }
    if (cacheBustingParam2) {
      url2.searchParams.set('_rsc', cacheBustingParam2)
    }

    const res = await next.fetch(url1.toString(), { headers: headers1 })
    expect(res.status).toBe(500)

    const res2 = await next.fetch(url2.toString(), { headers: headers2 })
    expect(res2.status).toBe(200)
  })
})