Abstract out stream related utils from render and web/utils

[shuding]

The readableStreamTee util is only used by server/render.tsx, but ended up in the middleware runtime bundle. So it's better to add all the utils in one place, and we can remove them once upstream implementation of ReadableStream is ready.

Bug

• Related issues linked using fixes #number
• Integration tests added
• Errors have helpful link attached, see contributing.md

Feature

• Implements an existing feature request or RFC. Make sure the feature request has been accepted for implementation before opening a PR.
• Related issues linked using fixes #number
• Integration tests added
• Documentation added
• Telemetry added. In case of a feature if it's used or not.
• Errors have helpful link attached, see contributing.md

Documentation / Examples

• Make sure the linting passes by running yarn lint

[ijjk]

Failing test suites

Commit: e970d58

yarn testheadless test/e2e/prerender.test.ts

• Prerender > should handle manual revalidate for fallback: blocking

Expand output

● Prerender › should handle manual revalidate for fallback: blocking

expect(received).toMatch(expected)

Expected pattern: /(HIT|STALE)/
Received string:  "MISS"

  1973 |         const html2 = await res2.text()
  1974 |         const $2 = cheerio.load(html2)
> 1975 |         expect(res2.headers.get('x-nextjs-cache')).toMatch(/(HIT|STALE)/)
       |                                                    ^
  1976 |
  1977 |         expect(initialTime).toBe($2('#time').text())
  1978 |

  at Object.<anonymous> (e2e/prerender.test.ts:1975:52)

Read more about building and testing Next.js in contributing.md.

[ijjk]

Stats from current PR

Default Build (Decrease detected ✓)

General Overall increase ⚠️

	vercel/next.js canary	shuding/next.js shu/45a2	Change
buildDuration	15.1s	15.2s	⚠️ +63ms
buildDurationCached	6s	6.1s	⚠️ +34ms
nodeModulesSize	456 MB	456 MB	⚠️ +4.14 kB

Page Load Tests Overall decrease ⚠️

	vercel/next.js canary	shuding/next.js shu/45a2	Change
/ failed reqs	0	0	✓
/ total time (seconds)	2.941	2.94	0
/ avg req/sec	849.99	850.25	+0.26
/error-in-render failed reqs	0	0	✓
/error-in-render total time (seconds)	1.171	1.176	0
/error-in-render avg req/sec	2135.36	2125.92	⚠️ -9.44

Client Bundles (main, webpack)

	vercel/next.js canary	shuding/next.js shu/45a2	Change
925.HASH.js gzip	179 B	179 B	✓
framework-HASH.js gzip	42 kB	42 kB	✓
main-HASH.js gzip	28 kB	28 kB	✓
webpack-HASH.js gzip	1.44 kB	1.44 kB	✓
Overall change	71.6 kB	71.6 kB	✓

Legacy Client Bundles (polyfills)

	vercel/next.js canary	shuding/next.js shu/45a2	Change
polyfills-HASH.js gzip	31 kB	31 kB	✓
Overall change	31 kB	31 kB	✓

Client Pages

	vercel/next.js canary	shuding/next.js shu/45a2	Change
_app-HASH.js gzip	1.36 kB	1.36 kB	✓
_error-HASH.js gzip	192 B	192 B	✓
amp-HASH.js gzip	309 B	309 B	✓
css-HASH.js gzip	327 B	327 B	✓
dynamic-HASH.js gzip	2.57 kB	2.57 kB	✓
head-HASH.js gzip	351 B	351 B	✓
hooks-HASH.js gzip	920 B	920 B	✓
image-HASH.js gzip	5.48 kB	5.48 kB	✓
index-HASH.js gzip	263 B	263 B	✓
link-HASH.js gzip	2.26 kB	2.26 kB	✓
routerDirect..HASH.js gzip	320 B	320 B	✓
script-HASH.js gzip	387 B	387 B	✓
withRouter-HASH.js gzip	319 B	319 B	✓
85e02e95b279..7e3.css gzip	107 B	107 B	✓
Overall change	15.2 kB	15.2 kB	✓

Client Build Manifests

	vercel/next.js canary	shuding/next.js shu/45a2	Change
_buildManifest.js gzip	460 B	460 B	✓
Overall change	460 B	460 B	✓

Rendered Page Sizes

	vercel/next.js canary	shuding/next.js shu/45a2	Change
index.html gzip	531 B	531 B	✓
link.html gzip	545 B	545 B	✓
withRouter.html gzip	525 B	525 B	✓
Overall change	1.6 kB	1.6 kB	✓

---

Default Build with SWC (Decrease detected ✓)

General Overall increase ⚠️

	vercel/next.js canary	shuding/next.js shu/45a2	Change
buildDuration	18.6s	18.7s	⚠️ +144ms
buildDurationCached	6s	6.1s	⚠️ +73ms
nodeModulesSize	456 MB	456 MB	⚠️ +4.14 kB

Page Load Tests Overall decrease ⚠️

	vercel/next.js canary	shuding/next.js shu/45a2	Change
/ failed reqs	0	0	✓
/ total time (seconds)	2.94	2.953	⚠️ +0.01
/ avg req/sec	850.22	846.65	⚠️ -3.57
/error-in-render failed reqs	0	0	✓
/error-in-render total time (seconds)	1.176	1.183	⚠️ +0.01
/error-in-render avg req/sec	2126.03	2112.94	⚠️ -13.09

Client Bundles (main, webpack)

	vercel/next.js canary	shuding/next.js shu/45a2	Change
925.HASH.js gzip	178 B	178 B	✓
framework-HASH.js gzip	42.3 kB	42.3 kB	✓
main-HASH.js gzip	28.2 kB	28.2 kB	✓
webpack-HASH.js gzip	1.45 kB	1.45 kB	✓
Overall change	72.1 kB	72.1 kB	✓

Legacy Client Bundles (polyfills)

	vercel/next.js canary	shuding/next.js shu/45a2	Change
polyfills-HASH.js gzip	31 kB	31 kB	✓
Overall change	31 kB	31 kB	✓

Client Pages

	vercel/next.js canary	shuding/next.js shu/45a2	Change
_app-HASH.js gzip	1.35 kB	1.35 kB	✓
_error-HASH.js gzip	179 B	179 B	✓
amp-HASH.js gzip	313 B	313 B	✓
css-HASH.js gzip	324 B	324 B	✓
dynamic-HASH.js gzip	2.56 kB	2.56 kB	✓
head-HASH.js gzip	351 B	351 B	✓
hooks-HASH.js gzip	921 B	921 B	✓
image-HASH.js gzip	5.59 kB	5.59 kB	✓
index-HASH.js gzip	261 B	261 B	✓
link-HASH.js gzip	2.33 kB	2.33 kB	✓
routerDirect..HASH.js gzip	322 B	322 B	✓
script-HASH.js gzip	388 B	388 B	✓
withRouter-HASH.js gzip	317 B	317 B	✓
85e02e95b279..7e3.css gzip	107 B	107 B	✓
Overall change	15.3 kB	15.3 kB	✓

Client Build Manifests

	vercel/next.js canary	shuding/next.js shu/45a2	Change
_buildManifest.js gzip	458 B	458 B	✓
Overall change	458 B	458 B	✓

Rendered Page Sizes

	vercel/next.js canary	shuding/next.js shu/45a2	Change
index.html gzip	531 B	531 B	✓
link.html gzip	546 B	546 B	✓
withRouter.html gzip	527 B	527 B	✓
Overall change	1.6 kB	1.6 kB	✓

Commit: cb11205