index.test.js

/* eslint-env jest */
import cheerio from 'cheerio'
import 'flat-map-polyfill'
import { pathExists, readdir, readFile, readJSON, remove } from 'fs-extra'
import {
  check,
  File,
  findPort,
  killApp,
  launchApp,
  nextBuild,
  nextStart,
  renderViaHTTP,
  waitFor,
} from 'next-test-utils'
import webdriver from 'next-webdriver'
import { join } from 'path'

jest.setTimeout(1000 * 60 * 2)

const fixturesDir = join(__dirname, '../..', 'css-fixtures')

describe('CSS Support', () => {
  describe('Basic Global Support', () => {
    const appDir = join(fixturesDir, 'single-global')

    beforeAll(async () => {
      await remove(join(appDir, '.next'))
    })

    it('should compile successfully', async () => {
      const { code, stdout } = await nextBuild(appDir, [], {
        stdout: true,
      })
      expect(code).toBe(0)
      expect(stdout).toMatch(/Compiled successfully/)
    })

    it(`should've emitted a single CSS file`, async () => {
      const cssFolder = join(appDir, '.next/static/css')

      const files = await readdir(cssFolder)
      const cssFiles = files.filter((f) => /\.css$/.test(f))

      expect(cssFiles.length).toBe(1)
      expect(await readFile(join(cssFolder, cssFiles[0]), 'utf8')).toContain(
        'color:red'
      )
    })
  })

  describe('Basic Global Support with src/ dir', () => {
    const appDir = join(fixturesDir, 'single-global-src')

    beforeAll(async () => {
      await remove(join(appDir, '.next'))
    })

    it('should compile successfully', async () => {
      const { code, stdout } = await nextBuild(appDir, [], {
        stdout: true,
      })
      expect(code).toBe(0)
      expect(stdout).toMatch(/Compiled successfully/)
    })

    it(`should've emitted a single CSS file`, async () => {
      const cssFolder = join(appDir, '.next/static/css')

      const files = await readdir(cssFolder)
      const cssFiles = files.filter((f) => /\.css$/.test(f))

      expect(cssFiles.length).toBe(1)
      expect(await readFile(join(cssFolder, cssFiles[0]), 'utf8')).toContain(
        'color:red'
      )
    })
  })

  describe('Multi Global Support', () => {
    const appDir = join(fixturesDir, 'multi-global')

    beforeAll(async () => {
      await remove(join(appDir, '.next'))
    })

    it('should compile successfully', async () => {
      const { code, stdout } = await nextBuild(appDir, [], {
        stdout: true,
      })
      expect(code).toBe(0)
      expect(stdout).toMatch(/Compiled successfully/)
    })

    it(`should've emitted a single CSS file`, async () => {
      const cssFolder = join(appDir, '.next/static/css')

      const files = await readdir(cssFolder)
      const cssFiles = files.filter((f) => /\.css$/.test(f))

      expect(cssFiles.length).toBe(1)
      const cssContent = await readFile(join(cssFolder, cssFiles[0]), 'utf8')
      expect(
        cssContent.replace(/\/\*.*?\*\//g, '').trim()
      ).toMatchInlineSnapshot(`".red-text{color:red}.blue-text{color:#00f}"`)
    })
  })

  describe('Nested @import() Global Support', () => {
    const appDir = join(fixturesDir, 'nested-global')

    beforeAll(async () => {
      await remove(join(appDir, '.next'))
    })

    it('should compile successfully', async () => {
      const { code, stdout } = await nextBuild(appDir, [], {
        stdout: true,
      })
      expect(code).toBe(0)
      expect(stdout).toMatch(/Compiled successfully/)
    })

    it(`should've emitted a single CSS file`, async () => {
      const cssFolder = join(appDir, '.next/static/css')

      const files = await readdir(cssFolder)
      const cssFiles = files.filter((f) => /\.css$/.test(f))

      expect(cssFiles.length).toBe(1)
      const cssContent = await readFile(join(cssFolder, cssFiles[0]), 'utf8')
      expect(
        cssContent.replace(/\/\*.*?\*\//g, '').trim()
      ).toMatchInlineSnapshot(
        `".red-text{color:purple;font-weight:bolder;color:red}.blue-text{color:orange;font-weight:bolder;color:#00f}"`
      )
    })
  })

  describe('CSS Compilation and Prefixing', () => {
    const appDir = join(fixturesDir, 'compilation-and-prefixing')

    beforeAll(async () => {
      await remove(join(appDir, '.next'))
    })

    it('should compile successfully', async () => {
      const { code, stdout } = await nextBuild(appDir, [], {
        stdout: true,
      })
      expect(code).toBe(0)
      expect(stdout).toMatch(/Compiled successfully/)
    })

    it(`should've compiled and prefixed`, async () => {
      const cssFolder = join(appDir, '.next/static/css')

      const files = await readdir(cssFolder)
      const cssFiles = files.filter((f) => /\.css$/.test(f))

      expect(cssFiles.length).toBe(1)
      const cssContent = await readFile(join(cssFolder, cssFiles[0]), 'utf8')
      expect(
        cssContent.replace(/\/\*.*?\*\//g, '').trim()
      ).toMatchInlineSnapshot(
        `"@media (min-width:480px) and (max-width:767px){::-moz-placeholder{color:green}:-ms-input-placeholder{color:green}::placeholder{color:green}}.flex-parsing{flex:0 0 calc(50% - var(--vertical-gutter))}.transform-parsing{transform:translate3d(0,0)}.css-grid-shorthand{grid-column:span 2}.g-docs-sidenav .filter::-webkit-input-placeholder{opacity:80%}"`
      )

      // Contains a source map
      expect(cssContent).toMatch(/\/\*#\s*sourceMappingURL=(.+\.map)\s*\*\//)
    })

    it(`should've emitted a source map`, async () => {
      const cssFolder = join(appDir, '.next/static/css')

      const files = await readdir(cssFolder)
      const cssMapFiles = files.filter((f) => /\.css\.map$/.test(f))

      expect(cssMapFiles.length).toBe(1)
      const cssMapContent = (
        await readFile(join(cssFolder, cssMapFiles[0]), 'utf8')
      ).trim()

      const { version, mappings, sourcesContent } = JSON.parse(cssMapContent)
      expect({ version, mappings, sourcesContent }).toMatchInlineSnapshot(`
        Object {
          "mappings": "AAAA,+CACE,mBACE,WACF,CAFA,uBACE,WACF,CAFA,cACE,WACF,CACF,CAEA,cACE,2CACF,CAEA,mBACE,0BACF,CAEA,oBACE,kBACF,CAEA,mDACE,WACF",
          "sourcesContent": Array [
            "@media (480px <= width < 768px) {
          ::placeholder {
            color: green;
          }
        }

        .flex-parsing {
          flex: 0 0 calc(50% - var(--vertical-gutter));
        }

        .transform-parsing {
          transform: translate3d(0px, 0px);
        }

        .css-grid-shorthand {
          grid-column: span 2;
        }

        .g-docs-sidenav .filter::-webkit-input-placeholder {
          opacity: 80%;
        }
        ",
          ],
          "version": 3,
        }
      `)
    })
  })

  // Tests css ordering
  describe('Multi Global Support (reversed)', () => {
    const appDir = join(fixturesDir, 'multi-global-reversed')

    beforeAll(async () => {
      await remove(join(appDir, '.next'))
    })

    it('should compile successfully', async () => {
      const { code, stdout } = await nextBuild(appDir, [], {
        stdout: true,
      })
      expect(code).toBe(0)
      expect(stdout).toMatch(/Compiled successfully/)
    })

    it(`should've emitted a single CSS file`, async () => {
      const cssFolder = join(appDir, '.next/static/css')

      const files = await readdir(cssFolder)
      const cssFiles = files.filter((f) => /\.css$/.test(f))

      expect(cssFiles.length).toBe(1)
      const cssContent = await readFile(join(cssFolder, cssFiles[0]), 'utf8')
      expect(
        cssContent.replace(/\/\*.*?\*\//g, '').trim()
      ).toMatchInlineSnapshot(`".blue-text{color:#00f}.red-text{color:red}"`)
    })
  })

  describe('React Lifecyce Order (dev)', () => {
    const appDir = join(fixturesDir, 'transition-react')
    beforeAll(async () => {
      await remove(join(appDir, '.next'))
    })

    let appPort
    let app
    beforeAll(async () => {
      appPort = await findPort()
      app = await launchApp(appDir, appPort)
    })
    afterAll(async () => {
      await killApp(app)
    })

    it('should have the correct color on mount after navigation', async () => {
      let browser
      try {
        browser = await webdriver(appPort, '/')

        // Navigate to other:
        await browser.waitForElementByCss('#link-other').click()
        const text = await browser.waitForElementByCss('#red-title').text()
        expect(text).toMatchInlineSnapshot(`"rgb(255, 0, 0)"`)
      } finally {
        if (browser) {
          await browser.close()
        }
      }
    })
  })

  describe('React Lifecyce Order (production)', () => {
    const appDir = join(fixturesDir, 'transition-react')
    beforeAll(async () => {
      await remove(join(appDir, '.next'))
    })

    let appPort
    let app
    let code
    let stdout
    beforeAll(async () => {
      ;({ code, stdout } = await nextBuild(appDir, [], {
        stdout: true,
      }))
      appPort = await findPort()
      app = await nextStart(appDir, appPort)
    })
    afterAll(async () => {
      await killApp(app)
    })

    it('should have compiled successfully', () => {
      expect(code).toBe(0)
      expect(stdout).toMatch(/Compiled successfully/)
    })

    it('should have the correct color on mount after navigation', async () => {
      let browser
      try {
        browser = await webdriver(appPort, '/')

        // Navigate to other:
        await browser.waitForElementByCss('#link-other').click()
        const text = await browser.waitForElementByCss('#red-title').text()
        expect(text).toMatchInlineSnapshot(`"rgb(255, 0, 0)"`)
      } finally {
        if (browser) {
          await browser.close()
        }
      }
    })
  })

  describe('Invalid CSS in _document', () => {
    const appDir = join(fixturesDir, 'invalid-module-document')

    beforeAll(async () => {
      await remove(join(appDir, '.next'))
    })

    it('should fail to build', async () => {
      const { code, stderr } = await nextBuild(appDir, [], {
        stderr: true,
      })
      expect(code).not.toBe(0)
      expect(stderr).toContain('Failed to compile')
      expect(stderr).toContain('styles.module.css')
      expect(stderr).toMatch(
        /CSS.*cannot.*be imported within.*pages[\\/]_document\.js/
      )
      expect(stderr).toMatch(/Location:.*pages[\\/]_document\.js/)
    })
  })

  describe('Invalid Global CSS', () => {
    const appDir = join(fixturesDir, 'invalid-global')

    beforeAll(async () => {
      await remove(join(appDir, '.next'))
    })

    it('should fail to build', async () => {
      const { code, stderr } = await nextBuild(appDir, [], {
        stderr: true,
      })
      expect(code).not.toBe(0)
      expect(stderr).toContain('Failed to compile')
      expect(stderr).toContain('styles/global.css')
      expect(stderr).toMatch(
        /Please move all global CSS imports.*?pages(\/|\\)_app/
      )
      expect(stderr).toMatch(/Location:.*pages[\\/]index\.js/)
    })
  })

  describe('Valid Global CSS from npm', () => {
    const appDir = join(fixturesDir, 'import-global-from-module')

    beforeAll(async () => {
      await remove(join(appDir, '.next'))
    })

    it('should compile successfully', async () => {
      const { code, stdout } = await nextBuild(appDir, [], {
        stdout: true,
      })
      expect(code).toBe(0)
      expect(stdout).toMatch(/Compiled successfully/)
    })

    it(`should've emitted a single CSS file`, async () => {
      const cssFolder = join(appDir, '.next/static/css')

      const files = await readdir(cssFolder)
      const cssFiles = files.filter((f) => /\.css$/.test(f))

      expect(cssFiles.length).toBe(1)
      const cssContent = await readFile(join(cssFolder, cssFiles[0]), 'utf8')
      expect(
        cssContent.replace(/\/\*.*?\*\//g, '').trim()
      ).toMatchInlineSnapshot(`".red-text{color:\\"red\\"}"`)
    })
  })

  describe('Invalid Global CSS with Custom App', () => {
    const appDir = join(fixturesDir, 'invalid-global-with-app')

    beforeAll(async () => {
      await remove(join(appDir, '.next'))
    })

    it('should fail to build', async () => {
      const { code, stderr } = await nextBuild(appDir, [], {
        stderr: true,
      })
      expect(code).not.toBe(0)
      expect(stderr).toContain('Failed to compile')
      expect(stderr).toContain('styles/global.css')
      expect(stderr).toMatch(
        /Please move all global CSS imports.*?pages(\/|\\)_app/
      )
      expect(stderr).toMatch(/Location:.*pages[\\/]index\.js/)
    })
  })

  describe('Valid and Invalid Global CSS with Custom App', () => {
    const appDir = join(fixturesDir, 'valid-and-invalid-global')

    beforeAll(async () => {
      await remove(join(appDir, '.next'))
    })

    it('should fail to build', async () => {
      const { code, stderr } = await nextBuild(appDir, [], {
        stderr: true,
      })
      expect(code).not.toBe(0)
      expect(stderr).toContain('Failed to compile')
      expect(stderr).toContain('styles/global.css')
      expect(stderr).toContain('Please move all global CSS imports')
      expect(stderr).toMatch(/Location:.*pages[\\/]index\.js/)
    })
  })

  describe('Can hot reload CSS without losing state', () => {
    const appDir = join(fixturesDir, 'multi-page')

    beforeAll(async () => {
      await remove(join(appDir, '.next'))
    })

    let appPort
    let app
    beforeAll(async () => {
      appPort = await findPort()
      app = await launchApp(appDir, appPort)
    })
    afterAll(async () => {
      await killApp(app)
    })

    it('should update CSS color without remounting <input>', async () => {
      let browser
      try {
        browser = await webdriver(appPort, '/page1')

        const desiredText = 'hello world'
        await browser.elementById('text-input').type(desiredText)
        expect(await browser.elementById('text-input').getValue()).toBe(
          desiredText
        )

        const currentColor = await browser.eval(
          `window.getComputedStyle(document.querySelector('.red-text')).color`
        )
        expect(currentColor).toMatchInlineSnapshot(`"rgb(255, 0, 0)"`)

        const cssFile = new File(join(appDir, 'styles/global1.css'))
        try {
          cssFile.replace('color: red', 'color: purple')

          await check(
            () =>
              browser.eval(
                `window.getComputedStyle(document.querySelector('.red-text')).color`
              ),
            'rgb(128, 0, 128)'
          )

          // ensure text remained
          expect(await browser.elementById('text-input').getValue()).toBe(
            desiredText
          )
        } finally {
          cssFile.restore()
        }
      } finally {
        if (browser) {
          await browser.close()
        }
      }
    })
  })

  describe('Has CSS in computed styles in Development', () => {
    const appDir = join(fixturesDir, 'multi-page')

    beforeAll(async () => {
      await remove(join(appDir, '.next'))
    })

    let appPort
    let app
    beforeAll(async () => {
      appPort = await findPort()
      app = await launchApp(appDir, appPort)
    })
    afterAll(async () => {
      await killApp(app)
    })

    it('should have CSS for page', async () => {
      let browser
      try {
        browser = await webdriver(appPort, '/page2')

        const currentColor = await browser.eval(
          `window.getComputedStyle(document.querySelector('.blue-text')).color`
        )
        expect(currentColor).toMatchInlineSnapshot(`"rgb(0, 0, 255)"`)
      } finally {
        if (browser) {
          await browser.close()
        }
      }
    })
  })

  describe('Body is not hidden when unused in Development', () => {
    const appDir = join(fixturesDir, 'unused')

    beforeAll(async () => {
      await remove(join(appDir, '.next'))
    })

    let appPort
    let app
    beforeAll(async () => {
      appPort = await findPort()
      app = await launchApp(appDir, appPort)
    })
    afterAll(async () => {
      await killApp(app)
    })

    it('should have body visible', async () => {
      let browser
      try {
        browser = await webdriver(appPort, '/')
        const currentDisplay = await browser.eval(
          `window.getComputedStyle(document.querySelector('body')).display`
        )
        expect(currentDisplay).toBe('block')
      } finally {
        if (browser) {
          await browser.close()
        }
      }
    })
  })

  describe('Body is not hidden when broken in Development', () => {
    const appDir = join(fixturesDir, 'unused')

    let appPort
    let app
    beforeAll(async () => {
      await remove(join(appDir, '.next'))
      appPort = await findPort()
      app = await launchApp(appDir, appPort)
    })
    afterAll(async () => {
      await killApp(app)
    })

    it('should have body visible', async () => {
      const pageFile = new File(join(appDir, 'pages/index.js'))
      let browser
      try {
        pageFile.replace('<div />', '<div>')
        await waitFor(2000) // wait for recompile

        browser = await webdriver(appPort, '/')
        const currentDisplay = await browser.eval(
          `window.getComputedStyle(document.querySelector('body')).display`
        )
        expect(currentDisplay).toBe('block')
      } finally {
        pageFile.restore()
        if (browser) {
          await browser.close()
        }
      }
    })
  })

  describe('Has CSS in computed styles in Production', () => {
    const appDir = join(fixturesDir, 'multi-page')

    let appPort
    let app
    let stdout
    let code
    beforeAll(async () => {
      await remove(join(appDir, '.next'))
      ;({ code, stdout } = await nextBuild(appDir, [], {
        stdout: true,
      }))
      appPort = await findPort()
      app = await nextStart(appDir, appPort)
    })
    afterAll(async () => {
      await killApp(app)
    })

    it('should have compiled successfully', () => {
      expect(code).toBe(0)
      expect(stdout).toMatch(/Compiled successfully/)
    })

    it('should have CSS for page', async () => {
      const browser = await webdriver(appPort, '/page2')

      const currentColor = await browser.eval(
        `window.getComputedStyle(document.querySelector('.blue-text')).color`
      )
      expect(currentColor).toMatchInlineSnapshot(`"rgb(0, 0, 255)"`)
    })

    it(`should've preloaded the CSS file and injected it in <head>`, async () => {
      const content = await renderViaHTTP(appPort, '/page2')
      const $ = cheerio.load(content)

      const cssPreload = $('link[rel="preload"][as="style"]')
      expect(cssPreload.length).toBe(1)
      expect(cssPreload.attr('href')).toMatch(/^\/_next\/static\/css\/.*\.css$/)

      const cssSheet = $('link[rel="stylesheet"]')
      expect(cssSheet.length).toBe(1)
      expect(cssSheet.attr('href')).toMatch(/^\/_next\/static\/css\/.*\.css$/)

      /* ensure CSS preloaded first */
      const allPreloads = [].slice.call($('link[rel="preload"]'))
      const styleIndexes = allPreloads.flatMap((p, i) =>
        p.attribs.as === 'style' ? i : []
      )
      expect(styleIndexes).toEqual([0])
    })
  })

  describe('CSS URL via `file-loader`', () => {
    const appDir = join(fixturesDir, 'url-global')

    beforeAll(async () => {
      await remove(join(appDir, '.next'))
    })

    it('should compile successfully', async () => {
      const { code, stdout } = await nextBuild(appDir, [], {
        stdout: true,
      })
      expect(code).toBe(0)
      expect(stdout).toMatch(/Compiled successfully/)
    })

    it(`should've emitted expected files`, async () => {
      const cssFolder = join(appDir, '.next/static/css')
      const mediaFolder = join(appDir, '.next/static/media')

      const files = await readdir(cssFolder)
      const cssFiles = files.filter((f) => /\.css$/.test(f))

      expect(cssFiles.length).toBe(1)
      const cssContent = await readFile(join(cssFolder, cssFiles[0]), 'utf8')
      expect(cssContent.replace(/\/\*.*?\*\//g, '').trim()).toMatch(
        /^\.red-text\{color:red;background-image:url\(\/_next\/static\/media\/dark\.[a-z0-9]{32}\.svg\) url\(\/_next\/static\/media\/dark2\.[a-z0-9]{32}\.svg\)\}\.blue-text\{color:orange;font-weight:bolder;background-image:url\(\/_next\/static\/media\/light\.[a-z0-9]{32}\.svg\);color:#00f\}$/
      )

      const mediaFiles = await readdir(mediaFolder)
      expect(mediaFiles.length).toBe(3)
      expect(
        mediaFiles
          .map((fileName) =>
            /^(.+?)\..{32}\.(.+?)$/.exec(fileName).slice(1).join('.')
          )
          .sort()
      ).toMatchInlineSnapshot(`
        Array [
          "dark.svg",
          "dark2.svg",
          "light.svg",
        ]
      `)
    })
  })

  describe('CSS URL via `file-loader` and asset prefix (1)', () => {
    const appDir = join(fixturesDir, 'url-global-asset-prefix-1')

    beforeAll(async () => {
      await remove(join(appDir, '.next'))
    })

    it('should compile successfully', async () => {
      const { code, stdout } = await nextBuild(appDir, [], {
        stdout: true,
      })
      expect(code).toBe(0)
      expect(stdout).toMatch(/Compiled successfully/)
    })

    it(`should've emitted expected files`, async () => {
      const cssFolder = join(appDir, '.next/static/css')
      const mediaFolder = join(appDir, '.next/static/media')

      const files = await readdir(cssFolder)
      const cssFiles = files.filter((f) => /\.css$/.test(f))

      expect(cssFiles.length).toBe(1)
      const cssContent = await readFile(join(cssFolder, cssFiles[0]), 'utf8')
      expect(cssContent.replace(/\/\*.*?\*\//g, '').trim()).toMatch(
        /^\.red-text\{color:red;background-image:url\(\/foo\/_next\/static\/media\/dark\.[a-z0-9]{32}\.svg\) url\(\/foo\/_next\/static\/media\/dark2\.[a-z0-9]{32}\.svg\)\}\.blue-text\{color:orange;font-weight:bolder;background-image:url\(\/foo\/_next\/static\/media\/light\.[a-z0-9]{32}\.svg\);color:#00f\}$/
      )

      const mediaFiles = await readdir(mediaFolder)
      expect(mediaFiles.length).toBe(3)
      expect(
        mediaFiles
          .map((fileName) =>
            /^(.+?)\..{32}\.(.+?)$/.exec(fileName).slice(1).join('.')
          )
          .sort()
      ).toMatchInlineSnapshot(`
        Array [
          "dark.svg",
          "dark2.svg",
          "light.svg",
        ]
      `)
    })
  })

  describe('CSS URL via `file-loader` and asset prefix (2)', () => {
    const appDir = join(fixturesDir, 'url-global-asset-prefix-2')

    beforeAll(async () => {
      await remove(join(appDir, '.next'))
    })

    it('should compile successfully', async () => {
      const { code, stdout } = await nextBuild(appDir, [], {
        stdout: true,
      })
      expect(code).toBe(0)
      expect(stdout).toMatch(/Compiled successfully/)
    })

    it(`should've emitted expected files`, async () => {
      const cssFolder = join(appDir, '.next/static/css')
      const mediaFolder = join(appDir, '.next/static/media')

      const files = await readdir(cssFolder)
      const cssFiles = files.filter((f) => /\.css$/.test(f))

      expect(cssFiles.length).toBe(1)
      const cssContent = await readFile(join(cssFolder, cssFiles[0]), 'utf8')
      expect(cssContent.replace(/\/\*.*?\*\//g, '').trim()).toMatch(
        /^\.red-text\{color:red;background-image:url\(\/foo\/_next\/static\/media\/dark\.[a-z0-9]{32}\.svg\) url\(\/foo\/_next\/static\/media\/dark2\.[a-z0-9]{32}\.svg\)\}\.blue-text\{color:orange;font-weight:bolder;background-image:url\(\/foo\/_next\/static\/media\/light\.[a-z0-9]{32}\.svg\);color:#00f\}$/
      )

      const mediaFiles = await readdir(mediaFolder)
      expect(mediaFiles.length).toBe(3)
      expect(
        mediaFiles
          .map((fileName) =>
            /^(.+?)\..{32}\.(.+?)$/.exec(fileName).slice(1).join('.')
          )
          .sort()
      ).toMatchInlineSnapshot(`
        Array [
          "dark.svg",
          "dark2.svg",
          "light.svg",
        ]
      `)
    })
  })

  describe('Good CSS Import from node_modules', () => {
    const appDir = join(fixturesDir, 'npm-import')

    beforeAll(async () => {
      await remove(join(appDir, '.next'))
    })

    it('should compile successfully', async () => {
      const { code, stdout } = await nextBuild(appDir, [], {
        stdout: true,
      })
      expect(code).toBe(0)
      expect(stdout).toMatch(/Compiled successfully/)
    })

    it(`should've emitted a single CSS file`, async () => {
      const cssFolder = join(appDir, '.next/static/css')

      const files = await readdir(cssFolder)
      const cssFiles = files.filter((f) => /\.css$/.test(f))

      expect(cssFiles.length).toBe(1)
      const cssContent = await readFile(join(cssFolder, cssFiles[0]), 'utf8')
      expect(cssContent.replace(/\/\*.*?\*\//g, '').trim()).toMatch(/nprogress/)
    })
  })

  describe('Good Nested CSS Import from node_modules', () => {
    const appDir = join(fixturesDir, 'npm-import-nested')

    beforeAll(async () => {
      await remove(join(appDir, '.next'))
    })

    it('should compile successfully', async () => {
      const { code, stdout } = await nextBuild(appDir, [], {
        stdout: true,
      })
      expect(code).toBe(0)
      expect(stdout).toMatch(/Compiled successfully/)
    })

    it(`should've emitted a single CSS file`, async () => {
      const cssFolder = join(appDir, '.next/static/css')

      const files = await readdir(cssFolder)
      const cssFiles = files.filter((f) => /\.css$/.test(f))

      expect(cssFiles.length).toBe(1)
      const cssContent = await readFile(join(cssFolder, cssFiles[0]), 'utf8')
      expect(
        cssContent.replace(/\/\*.*?\*\//g, '').trim()
      ).toMatchInlineSnapshot(`".other{color:#00f}.test{color:red}"`)
    })
  })

  describe('CSS Import from node_modules', () => {
    const appDir = join(fixturesDir, 'npm-import-bad')

    beforeAll(async () => {
      await remove(join(appDir, '.next'))
    })

    it('should fail the build', async () => {
      const { code, stderr } = await nextBuild(appDir, [], { stderr: true })

      expect(code).toBe(0)
      expect(stderr).not.toMatch(/Can't resolve '[^']*?nprogress[^']*?'/)
      expect(stderr).not.toMatch(/Build error occurred/)
    })
  })

  describe('Ordering with styled-jsx (dev)', () => {
    const appDir = join(fixturesDir, 'with-styled-jsx')

    let appPort
    let app
    beforeAll(async () => {
      await remove(join(appDir, '.next'))
      appPort = await findPort()
      app = await launchApp(appDir, appPort)
    })
    afterAll(async () => {
      await killApp(app)
    })

    it('should have the correct color (css ordering)', async () => {
      const browser = await webdriver(appPort, '/')

      const currentColor = await browser.eval(
        `window.getComputedStyle(document.querySelector('.my-text')).color`
      )
      expect(currentColor).toMatchInlineSnapshot(`"rgb(0, 128, 0)"`)
    })
  })

  describe('Ordering with styled-jsx (prod)', () => {
    const appDir = join(fixturesDir, 'with-styled-jsx')

    let appPort
    let app
    let stdout
    let code
    beforeAll(async () => {
      await remove(join(appDir, '.next'))
      ;({ code, stdout } = await nextBuild(appDir, [], {
        stdout: true,
      }))
      appPort = await findPort()
      app = await nextStart(appDir, appPort)
    })
    afterAll(async () => {
      await killApp(app)
    })

    it('should have compiled successfully', () => {
      expect(code).toBe(0)
      expect(stdout).toMatch(/Compiled successfully/)
    })

    it('should have the correct color (css ordering)', async () => {
      const browser = await webdriver(appPort, '/')

      const currentColor = await browser.eval(
        `window.getComputedStyle(document.querySelector('.my-text')).color`
      )
      expect(currentColor).toMatchInlineSnapshot(`"rgb(0, 128, 0)"`)
    })
  })

  describe('Ordering with Global CSS and Modules (dev)', () => {
    const appDir = join(fixturesDir, 'global-and-module-ordering')

    let appPort
    let app
    beforeAll(async () => {
      await remove(join(appDir, '.next'))
      appPort = await findPort()
      app = await launchApp(appDir, appPort)
    })
    afterAll(async () => {
      await killApp(app)
    })

    it('should not execute scripts in any order', async () => {
      const content = await renderViaHTTP(appPort, '/')
      const $ = cheerio.load(content)

      let asyncCount = 0
      let totalCount = 0
      for (const script of $('script').toArray()) {
        ++totalCount
        if ('async' in script.attribs) {
          ++asyncCount
        }
      }

      expect(asyncCount).toBe(0)
      expect(totalCount).not.toBe(0)
    })

    it('should have the correct color (css ordering)', async () => {
      const browser = await webdriver(appPort, '/')

      const currentColor = await browser.eval(
        `window.getComputedStyle(document.querySelector('#blueText')).color`
      )
      expect(currentColor).toMatchInlineSnapshot(`"rgb(0, 0, 255)"`)
    })

    it('should have the correct color (css ordering) during hot reloads', async () => {
      let browser
      try {
        browser = await webdriver(appPort, '/')

        const blueColor = await browser.eval(
          `window.getComputedStyle(document.querySelector('#blueText')).color`
        )
        expect(blueColor).toMatchInlineSnapshot(`"rgb(0, 0, 255)"`)

        const yellowColor = await browser.eval(
          `window.getComputedStyle(document.querySelector('#yellowText')).color`
        )
        expect(yellowColor).toMatchInlineSnapshot(`"rgb(255, 255, 0)"`)

        const cssFile = new File(join(appDir, 'pages/index.module.css'))
        try {
          cssFile.replace('color: yellow;', 'color: rgb(1, 1, 1);')
          await check(
            () =>
              browser.eval(
                `window.getComputedStyle(document.querySelector('#yellowText')).color`
              ),
            'rgb(1, 1, 1)'
          )
          await check(
            () =>
              browser.eval(
                `window.getComputedStyle(document.querySelector('#blueText')).color`
              ),
            'rgb(0, 0, 255)'
          )
        } finally {
          cssFile.restore()
        }
      } finally {
        if (browser) {
          await browser.close()
        }
      }
    })
  })

  describe('Ordering with Global CSS and Modules (prod)', () => {
    const appDir = join(fixturesDir, 'global-and-module-ordering')

    let appPort
    let app
    let stdout
    let code
    beforeAll(async () => {
      await remove(join(appDir, '.next'))
      ;({ code, stdout } = await nextBuild(appDir, [], {
        stdout: true,
      }))
      appPort = await findPort()
      app = await nextStart(appDir, appPort)
    })
    afterAll(async () => {
      await killApp(app)
    })

    it('should have compiled successfully', () => {
      expect(code).toBe(0)
      expect(stdout).toMatch(/Compiled successfully/)
    })

    it('should have the correct color (css ordering)', async () => {
      const browser = await webdriver(appPort, '/')

      const currentColor = await browser.eval(
        `window.getComputedStyle(document.querySelector('#blueText')).color`
      )
      expect(currentColor).toMatchInlineSnapshot(`"rgb(0, 0, 255)"`)
    })
  })

  // https://github.com/vercel/next.js/issues/15468
  describe('CSS Property Ordering', () => {
    const appDir = join(fixturesDir, 'next-issue-15468')

    let appPort
    let app
    let stdout
    let code
    beforeAll(async () => {
      await remove(join(appDir, '.next'))
      ;({ code, stdout } = await nextBuild(appDir, [], {
        stdout: true,
      }))
      appPort = await findPort()
      app = await nextStart(appDir, appPort)
    })
    afterAll(async () => {
      await killApp(app)
    })

    it('should have compiled successfully', () => {
      expect(code).toBe(0)
      expect(stdout).toMatch(/Compiled successfully/)
    })

    it('should have the border width (property ordering)', async () => {
      const browser = await webdriver(appPort, '/')

      const width1 = await browser.eval(
        `window.getComputedStyle(document.querySelector('.test1')).borderWidth`
      )
      expect(width1).toMatchInlineSnapshot(`"0px"`)

      const width2 = await browser.eval(
        `window.getComputedStyle(document.querySelector('.test2')).borderWidth`
      )
      expect(width2).toMatchInlineSnapshot(`"5px"`)
    })
  })

  describe('Basic Tailwind CSS', () => {
    const appDir = join(fixturesDir, 'with-tailwindcss')

    beforeAll(async () => {
      await remove(join(appDir, '.next'))
    })

    it('should compile successfully', async () => {
      const { code, stdout } = await nextBuild(appDir, [], {
        stdout: true,
      })
      expect(code).toBe(0)
      expect(stdout).toMatch(/Compiled successfully/)
      expect(stdout).toContain('.css')
    })

    it(`should've compiled and prefixed`, async () => {
      const cssFolder = join(appDir, '.next/static/css')

      const files = await readdir(cssFolder)
      const cssFiles = files.filter((f) => /\.css$/.test(f))

      expect(cssFiles.length).toBe(1)
      const cssContent = await readFile(join(cssFolder, cssFiles[0]), 'utf8')

      expect(cssContent).toMatch(/object-right-bottom/) // look for tailwind's CSS
      expect(cssContent).not.toMatch(/tailwind/) // ensure @tailwind was removed

      // Contains a source map
      expect(cssContent).toMatch(/\/\*#\s*sourceMappingURL=(.+\.map)\s*\*\//)
    })

    it(`should've emitted a source map`, async () => {
      const cssFolder = join(appDir, '.next/static/css')

      const files = await readdir(cssFolder)
      const cssMapFiles = files.filter((f) => /\.css\.map$/.test(f))

      expect(cssMapFiles.length).toBe(1)
    })
  })

  describe('Tailwind and Purge CSS', () => {
    const appDir = join(fixturesDir, 'with-tailwindcss-and-purgecss')

    beforeAll(async () => {
      await remove(join(appDir, '.next'))
    })

    it('should compile successfully', async () => {
      const { code, stdout } = await nextBuild(appDir, [], {
        stdout: true,
      })
      expect(code).toBe(0)
      expect(stdout).toMatch(/Compiled successfully/)
    })

    it(`should've compiled and prefixed`, async () => {
      const cssFolder = join(appDir, '.next/static/css')

      const files = await readdir(cssFolder)
      const cssFiles = files.filter((f) => /\.css$/.test(f))

      expect(cssFiles.length).toBe(1)
      const cssContent = await readFile(join(cssFolder, cssFiles[0]), 'utf8')

      expect(cssContent).not.toMatch(/object-right-bottom/) // this was unused and should be gone
      expect(cssContent).toMatch(/text-blue-500/) // this was used
      expect(cssContent).not.toMatch(/tailwind/) // ensure @tailwind was removed

      // Contains a source map
      expect(cssContent).toMatch(/\/\*#\s*sourceMappingURL=(.+\.map)\s*\*\//)
    })

    it(`should've emitted a source map`, async () => {
      const cssFolder = join(appDir, '.next/static/css')

      const files = await readdir(cssFolder)
      const cssMapFiles = files.filter((f) => /\.css\.map$/.test(f))

      expect(cssMapFiles.length).toBe(1)
    })
  })

  // https://github.com/vercel/next.js/issues/18557
  describe('CSS page transition inject <style> with nonce so it works with CSP header', () => {
    const appDir = join(fixturesDir, 'csp-style-src-nonce')
    let app, appPort

    function tests() {
      async function checkGreenTitle(browser) {
        await browser.waitForElementByCss('#green-title')
        const titleColor = await browser.eval(
          `window.getComputedStyle(document.querySelector('#green-title')).color`
        )
        expect(titleColor).toBe('rgb(0, 128, 0)')
      }
      async function checkBlueTitle(browser) {
        await browser.waitForElementByCss('#blue-title')
        const titleColor = await browser.eval(
          `window.getComputedStyle(document.querySelector('#blue-title')).color`
        )
        expect(titleColor).toBe('rgb(0, 0, 255)')
      }

      it('should have correct color on index page (on load)', async () => {
        const browser = await webdriver(appPort, '/')
        try {
          await checkGreenTitle(browser)
        } finally {
          await browser.close()
        }
      })

      it('should have correct color on index page (on hover)', async () => {
        const browser = await webdriver(appPort, '/')
        try {
          await checkGreenTitle(browser)
          await browser.waitForElementByCss('#link-other').moveTo()
          await waitFor(2000)
          await checkGreenTitle(browser)
        } finally {
          await browser.close()
        }
      })

      it('should not change color on hover', async () => {
        const browser = await webdriver(appPort, '/')
        try {
          await checkGreenTitle(browser)
          await browser.waitForElementByCss('#link-other').moveTo()
          await waitFor(2000)
          await checkGreenTitle(browser)
        } finally {
          await browser.close()
        }
      })

      it('should have correct CSS injection order', async () => {
        const browser = await webdriver(appPort, '/')
        try {
          await checkGreenTitle(browser)

          const prevSiblingHref = await browser.eval(
            `document.querySelector('link[rel=stylesheet][data-n-p]').previousSibling.getAttribute('href')`
          )
          const currentPageHref = await browser.eval(
            `document.querySelector('link[rel=stylesheet][data-n-p]').getAttribute('href')`
          )
          expect(prevSiblingHref).toBeDefined()
          expect(prevSiblingHref).toBe(currentPageHref)

          // Navigate to other:
          await browser.waitForElementByCss('#link-other').click()
          await checkBlueTitle(browser)

          const newPrevSibling = await browser.eval(
            `document.querySelector('style[data-n-href]').previousSibling.getAttribute('data-n-css')`
          )
          const newPageHref = await browser.eval(
            `document.querySelector('style[data-n-href]').getAttribute('data-n-href')`
          )
          expect(newPrevSibling).toBe('VmVyY2Vs')
          expect(newPageHref).toBeDefined()
          expect(newPageHref).not.toBe(currentPageHref)

          // Navigate to home:
          await browser.waitForElementByCss('#link-index').click()
          await checkGreenTitle(browser)

          const newPrevSibling2 = await browser.eval(
            `document.querySelector('style[data-n-href]').previousSibling.getAttribute('data-n-css')`
          )
          const newPageHref2 = await browser.eval(
            `document.querySelector('style[data-n-href]').getAttribute('data-n-href')`
          )
          expect(newPrevSibling2).toBeTruthy()
          expect(newPageHref2).toBeDefined()
          expect(newPageHref2).toBe(currentPageHref)
        } finally {
          await browser.close()
        }
      })

      it('should have correct color on index page (on nav from index)', async () => {
        const browser = await webdriver(appPort, '/')
        try {
          await checkGreenTitle(browser)
          await browser.waitForElementByCss('#link-other').click()

          // Wait for navigation:
          await browser.waitForElementByCss('#link-index')
          await checkBlueTitle(browser)

          // Navigate back to index:
          await browser.waitForElementByCss('#link-index').click()
          await checkGreenTitle(browser)
        } finally {
          await browser.close()
        }
      })

      it('should have correct color on index page (on nav from other)', async () => {
        const browser = await webdriver(appPort, '/other')
        try {
          await checkBlueTitle(browser)
          await browser.waitForElementByCss('#link-index').click()

          // Wait for navigation:
          await browser.waitForElementByCss('#link-other')
          await checkGreenTitle(browser)

          // Navigate back to other:
          await browser.waitForElementByCss('#link-other').click()
          await checkBlueTitle(browser)
        } finally {
          await browser.close()
        }
      })
    }

    describe('Production Mode', () => {
      beforeAll(async () => {
        await remove(join(appDir, '.next'))
      })
      beforeAll(async () => {
        await nextBuild(appDir, [], {})
        appPort = await findPort()
        app = await nextStart(appDir, appPort)
      })
      afterAll(async () => {
        await killApp(app)
      })

      tests()
    })
  })

  // https://github.com/vercel/next.js/issues/12445
  describe('CSS Modules Composes Ordering', () => {
    const appDir = join(fixturesDir, 'composes-ordering')
    let app, appPort

    function tests(isDev = false) {
      async function checkBlackTitle(browser) {
        await browser.waitForElementByCss('#black-title')
        const titleColor = await browser.eval(
          `window.getComputedStyle(document.querySelector('#black-title')).color`
        )
        expect(titleColor).toBe('rgb(17, 17, 17)')
      }
      async function checkRedTitle(browser) {
        await browser.waitForElementByCss('#red-title')
        const titleColor = await browser.eval(
          `window.getComputedStyle(document.querySelector('#red-title')).color`
        )
        expect(titleColor).toBe('rgb(255, 0, 0)')
      }

      it('should have correct color on index page (on load)', async () => {
        const browser = await webdriver(appPort, '/')
        try {
          await checkBlackTitle(browser)
        } finally {
          await browser.close()
        }
      })

      it('should have correct color on index page (on hover)', async () => {
        const browser = await webdriver(appPort, '/')
        try {
          await checkBlackTitle(browser)
          await browser.waitForElementByCss('#link-other').moveTo()
          await waitFor(2000)
          await checkBlackTitle(browser)
        } finally {
          await browser.close()
        }
      })

      if (!isDev) {
        it('should not change color on hover', async () => {
          const browser = await webdriver(appPort, '/')
          try {
            await checkBlackTitle(browser)
            await browser.waitForElementByCss('#link-other').moveTo()
            await waitFor(2000)
            await checkBlackTitle(browser)
          } finally {
            await browser.close()
          }
        })

        it('should have correct CSS injection order', async () => {
          const browser = await webdriver(appPort, '/')
          try {
            await checkBlackTitle(browser)

            const prevSiblingHref = await browser.eval(
              `document.querySelector('link[rel=stylesheet][data-n-p]').previousSibling.getAttribute('href')`
            )
            const currentPageHref = await browser.eval(
              `document.querySelector('link[rel=stylesheet][data-n-p]').getAttribute('href')`
            )
            expect(prevSiblingHref).toBeDefined()
            expect(prevSiblingHref).toBe(currentPageHref)

            // Navigate to other:
            await browser.waitForElementByCss('#link-other').click()
            await checkRedTitle(browser)

            const newPrevSibling = await browser.eval(
              `document.querySelector('style[data-n-href]').previousSibling.getAttribute('data-n-css')`
            )
            const newPageHref = await browser.eval(
              `document.querySelector('style[data-n-href]').getAttribute('data-n-href')`
            )
            expect(newPrevSibling).toBe('')
            expect(newPageHref).toBeDefined()
            expect(newPageHref).not.toBe(currentPageHref)

            // Navigate to home:
            await browser.waitForElementByCss('#link-index').click()
            await checkBlackTitle(browser)

            const newPrevSibling2 = await browser.eval(
              `document.querySelector('style[data-n-href]').previousSibling.getAttribute('data-n-css')`
            )
            const newPageHref2 = await browser.eval(
              `document.querySelector('style[data-n-href]').getAttribute('data-n-href')`
            )
            expect(newPrevSibling2).toBe('')
            expect(newPageHref2).toBeDefined()
            expect(newPageHref2).toBe(currentPageHref)
          } finally {
            await browser.close()
          }
        })
      }

      it('should have correct color on index page (on nav from index)', async () => {
        const browser = await webdriver(appPort, '/')
        try {
          await checkBlackTitle(browser)
          await browser.waitForElementByCss('#link-other').click()

          // Wait for navigation:
          await browser.waitForElementByCss('#link-index')
          await checkRedTitle(browser)

          // Navigate back to index:
          await browser.waitForElementByCss('#link-index').click()
          await checkBlackTitle(browser)
        } finally {
          await browser.close()
        }
      })

      it('should have correct color on index page (on nav from other)', async () => {
        const browser = await webdriver(appPort, '/other')
        try {
          await checkRedTitle(browser)
          await browser.waitForElementByCss('#link-index').click()

          // Wait for navigation:
          await browser.waitForElementByCss('#link-other')
          await checkBlackTitle(browser)

          // Navigate back to other:
          await browser.waitForElementByCss('#link-other').click()
          await checkRedTitle(browser)
        } finally {
          await browser.close()
        }
      })
    }

    describe('Development Mode', () => {
      beforeAll(async () => {
        await remove(join(appDir, '.next'))
      })
      beforeAll(async () => {
        appPort = await findPort()
        app = await launchApp(appDir, appPort)
      })
      afterAll(async () => {
        await killApp(app)
      })

      tests(true)
    })

    describe('Production Mode', () => {
      beforeAll(async () => {
        await remove(join(appDir, '.next'))
      })
      beforeAll(async () => {
        await nextBuild(appDir, [], {})
        appPort = await findPort()
        app = await nextStart(appDir, appPort)
      })
      afterAll(async () => {
        await killApp(app)
      })

      tests()
    })
  })

  describe('CSS Cleanup on Render Failure', () => {
    const appDir = join(fixturesDir, 'transition-cleanup')
    let app, appPort

    function tests() {
      async function checkBlackTitle(browser) {
        await browser.waitForElementByCss('#black-title')
        const titleColor = await browser.eval(
          `window.getComputedStyle(document.querySelector('#black-title')).color`
        )
        expect(titleColor).toBe('rgb(17, 17, 17)')
      }

      it('not have intermediary page styles on error rendering', async () => {
        const browser = await webdriver(appPort, '/')
        try {
          await checkBlackTitle(browser)

          const currentPageStyles = await browser.eval(
            `document.querySelector('link[rel=stylesheet][data-n-p]')`
          )
          expect(currentPageStyles).toBeDefined()

          // Navigate to other:
          await browser.waitForElementByCss('#link-other').click()
          await check(
            () => browser.eval(`document.body.innerText`),
            'An unexpected error has occurred.',
            true
          )

          const newPageStyles = await browser.eval(
            `document.querySelector('link[rel=stylesheet][data-n-p]')`
          )
          expect(newPageStyles).toBeFalsy()

          const allPageStyles = await browser.eval(
            `document.querySelector('link[rel=stylesheet]')`
          )
          expect(allPageStyles).toBeFalsy()
        } finally {
          await browser.close()
        }
      })
    }

    describe('Production Mode', () => {
      beforeAll(async () => {
        await remove(join(appDir, '.next'))
      })
      beforeAll(async () => {
        await nextBuild(appDir, [], {})
        appPort = await findPort()
        app = await nextStart(appDir, appPort)
      })
      afterAll(async () => {
        await killApp(app)
      })

      tests()
    })
  })

  describe('Page reload on CSS missing', () => {
    const appDir = join(fixturesDir, 'transition-reload')
    let app, appPort

    function tests() {
      async function checkBlackTitle(browser) {
        await browser.waitForElementByCss('#black-title')
        const titleColor = await browser.eval(
          `window.getComputedStyle(document.querySelector('#black-title')).color`
        )
        expect(titleColor).toBe('rgb(17, 17, 17)')
      }

      it('should fall back to server-side transition on missing CSS', async () => {
        const browser = await webdriver(appPort, '/')
        try {
          await checkBlackTitle(browser)
          await browser.eval(`window.__priorNavigatePageState = 'OOF';`)

          // Navigate to other:
          await browser.waitForElementByCss('#link-other').click()
          // Wait for navigation:
          await browser.waitForElementByCss('#link-index')

          const state = await browser.eval(`window.__priorNavigatePageState`)
          expect(state).toBeFalsy()
        } finally {
          await browser.close()
        }
      })
    }

    describe('Production Mode', () => {
      beforeAll(async () => {
        await remove(join(appDir, '.next'))
      })
      beforeAll(async () => {
        await nextBuild(appDir, [], {})
        appPort = await findPort()
        app = await nextStart(appDir, appPort)

        // Remove other page CSS files:
        const manifest = await readJSON(
          join(appDir, '.next', 'build-manifest.json')
        )
        const files = manifest['pages']['/other'].filter((e) =>
          e.endsWith('.css')
        )
        if (files.length < 1) throw new Error()
        await Promise.all(files.map((f) => remove(join(appDir, '.next', f))))
      })
      afterAll(async () => {
        await killApp(app)
      })

      tests()
    })
  })

  describe('Page hydrates with CSS and not waiting on dependencies', () => {
    const appDir = join(fixturesDir, 'hydrate-without-deps')
    let app, appPort

    function tests() {
      async function checkBlackTitle(browser) {
        await browser.waitForElementByCss('#black-title')
        const titleColor = await browser.eval(
          `window.getComputedStyle(document.querySelector('#black-title')).color`
        )
        expect(titleColor).toBe('rgb(17, 17, 17)')
      }
      async function checkRedTitle(browser) {
        await browser.waitForElementByCss('#red-title')
        const titleColor = await browser.eval(
          `window.getComputedStyle(document.querySelector('#red-title')).color`
        )
        expect(titleColor).toBe('rgb(255, 0, 0)')
      }

      it('should hydrate black without dependencies manifest', async () => {
        const browser = await webdriver(appPort, '/')
        try {
          await checkBlackTitle(browser)
          await check(
            () => browser.eval(`document.querySelector('p').innerText`),
            'mounted'
          )
        } finally {
          await browser.close()
        }
      })

      it('should hydrate red without dependencies manifest', async () => {
        const browser = await webdriver(appPort, '/client')
        try {
          await checkRedTitle(browser)
          await check(
            () => browser.eval(`document.querySelector('p').innerText`),
            'mounted'
          )
        } finally {
          await browser.close()
        }
      })

      it('should route from black to red without dependencies', async () => {
        const browser = await webdriver(appPort, '/')
        try {
          await checkBlackTitle(browser)
          await check(
            () => browser.eval(`document.querySelector('p').innerText`),
            'mounted'
          )
          await browser.eval(`document.querySelector('#link-client').click()`)
          await checkRedTitle(browser)
          await check(
            () => browser.eval(`document.querySelector('p').innerText`),
            'mounted'
          )
        } finally {
          await browser.close()
        }
      })
    }

    describe('Production Mode', () => {
      beforeAll(async () => {
        await remove(join(appDir, '.next'))
      })
      beforeAll(async () => {
        await nextBuild(appDir, [], {})
        appPort = await findPort()
        app = await nextStart(appDir, appPort)

        const buildId = (
          await readFile(join(appDir, '.next', 'BUILD_ID'), 'utf8')
        ).trim()
        const fileName = join(
          appDir,
          '.next/static/',
          buildId,
          '_buildManifest.js'
        )
        if (!(await pathExists(fileName))) {
          throw new Error('Missing build manifest')
        }
        await remove(fileName)
      })
      afterAll(async () => {
        await killApp(app)
      })

      tests()
    })
  })

  // https://github.com/vercel/next.js/issues/12343
  describe('Basic CSS Modules Ordering', () => {
    const appDir = join(fixturesDir, 'next-issue-12343')
    let app, appPort

    function tests() {
      async function checkGreenButton(browser) {
        await browser.waitForElementByCss('#link-other')
        const titleColor = await browser.eval(
          `window.getComputedStyle(document.querySelector('#link-other')).backgroundColor`
        )
        expect(titleColor).toBe('rgb(0, 255, 0)')
      }
      async function checkPinkButton(browser) {
        await browser.waitForElementByCss('#link-index')
        const titleColor = await browser.eval(
          `window.getComputedStyle(document.querySelector('#link-index')).backgroundColor`
        )
        expect(titleColor).toBe('rgb(255, 105, 180)')
      }

      it('should have correct color on index page (on load)', async () => {
        const browser = await webdriver(appPort, '/')
        try {
          await checkGreenButton(browser)
        } finally {
          await browser.close()
        }
      })

      it('should have correct color on index page (on hover)', async () => {
        const browser = await webdriver(appPort, '/')
        try {
          await checkGreenButton(browser)
          await browser.waitForElementByCss('#link-other').moveTo()
          await waitFor(2000)
          await checkGreenButton(browser)
        } finally {
          await browser.close()
        }
      })

      it('should have correct color on index page (on nav)', async () => {
        const browser = await webdriver(appPort, '/')
        try {
          await checkGreenButton(browser)
          await browser.waitForElementByCss('#link-other').click()

          // Wait for navigation:
          await browser.waitForElementByCss('#link-index')
          await checkPinkButton(browser)

          // Navigate back to index:
          await browser.waitForElementByCss('#link-index').click()
          await checkGreenButton(browser)
        } finally {
          await browser.close()
        }
      })
    }

    describe('Development Mode', () => {
      beforeAll(async () => {
        await remove(join(appDir, '.next'))
      })
      beforeAll(async () => {
        appPort = await findPort()
        app = await launchApp(appDir, appPort)
      })
      afterAll(async () => {
        await killApp(app)
      })

      tests()
    })

    describe('Production Mode', () => {
      beforeAll(async () => {
        await remove(join(appDir, '.next'))
      })
      beforeAll(async () => {
        await nextBuild(appDir, [], {})
        appPort = await findPort()
        app = await nextStart(appDir, appPort)
      })
      afterAll(async () => {
        await killApp(app)
      })

      tests()
    })
  })

  describe('should handle unresolved files gracefully', () => {
    const workDir = join(fixturesDir, 'unresolved-css-url')

    it('should build correctly', async () => {
      await remove(join(workDir, '.next'))
      const { code } = await nextBuild(workDir)
      expect(code).toBe(0)
    })

    it('should have correct file references in CSS output', async () => {
      const cssFiles = await readdir(join(workDir, '.next/static/css'))

      for (const file of cssFiles) {
        if (file.endsWith('.css.map')) continue

        const content = await readFile(
          join(workDir, '.next/static/css', file),
          'utf8'
        )
        console.log(file, content)

        // if it is the combined global CSS file there are double the expected
        // results
        const howMany = content.includes('p{') || content.includes('p,') ? 2 : 1

        expect(content.match(/\(\/vercel\.svg/g).length).toBe(howMany)
        // expect(content.match(/\(vercel\.svg/g).length).toBe(howMany)
        expect(content.match(/\(\/_next\/static\/media/g).length).toBe(1)
        expect(content.match(/\(https:\/\//g).length).toBe(howMany)
      }
    })
  })
})