fix memory leak in require.cache

[sokra]

Previously only the top-level page would be cleared from the require cache, with this change it also clears module.parent and modules.children.

[ijjk]

Stats from current PR

Default Server Mode (Increase detected ⚠️)

General Overall increase ⚠️

	vercel/next.js canary	vercel/next.js memory/leak-require-cache	Change
buildDuration	13.5s	13.5s	⚠️ +87ms
buildDurationCached	4.5s	4.3s	-224ms
nodeModulesSize	46.6 MB	46.6 MB	⚠️ +1.81 kB

Page Load Tests Overall increase ✓

	vercel/next.js canary	vercel/next.js memory/leak-require-cache	Change
/ failed reqs	0	0	✓
/ total time (seconds)	2.277	2.285	⚠️ +0.01
/ avg req/sec	1097.77	1094.2	⚠️ -3.57
/error-in-render failed reqs	0	0	✓
/error-in-render total time (seconds)	1.188	1.173	-0.01
/error-in-render avg req/sec	2104.18	2130.64	+26.46

Client Bundles (main, webpack, commons)

	vercel/next.js canary	vercel/next.js memory/leak-require-cache	Change
framework-HASH.js gzip	39.3 kB	39.3 kB	✓
main-HASH.js gzip	19.3 kB	19.3 kB	✓
webpack-HASH.js gzip	996 B	996 B	✓
Overall change	59.6 kB	59.6 kB	✓

Legacy Client Bundles (polyfills)

	vercel/next.js canary	vercel/next.js memory/leak-require-cache	Change
polyfills-HASH.js gzip	31.1 kB	31.1 kB	✓
Overall change	31.1 kB	31.1 kB	✓

Client Pages

	vercel/next.js canary	vercel/next.js memory/leak-require-cache	Change
_app-HASH.js gzip	1.02 kB	1.02 kB	✓
_error-HASH.js gzip	3.04 kB	3.04 kB	✓
amp-HASH.js gzip	526 B	526 B	✓
css-HASH.js gzip	334 B	334 B	✓
hooks-HASH.js gzip	890 B	890 B	✓
index-HASH.js gzip	262 B	262 B	✓
link-HASH.js gzip	1.65 kB	1.65 kB	✓
routerDirect..HASH.js gzip	331 B	331 B	✓
withRouter-HASH.js gzip	329 B	329 B	✓
99a142a5cfae..804.css gzip	125 B	125 B	✓
Overall change	8.51 kB	8.51 kB	✓

Client Build Manifests

	vercel/next.js canary	vercel/next.js memory/leak-require-cache	Change
_buildManifest.js gzip	393 B	393 B	✓
Overall change	393 B	393 B	✓

Rendered Page Sizes

	vercel/next.js canary	vercel/next.js memory/leak-require-cache	Change
index.html gzip	561 B	561 B	✓
link.html gzip	570 B	570 B	✓
withRouter.html gzip	557 B	557 B	✓
Overall change	1.69 kB	1.69 kB	✓

---

Serverless Mode (Decrease detected ✓)

General Overall increase ⚠️

	vercel/next.js canary	vercel/next.js memory/leak-require-cache	Change
buildDuration	16.9s	16.8s	-77ms
buildDurationCached	6.3s	6.3s	⚠️ +12ms
nodeModulesSize	46.6 MB	46.6 MB	⚠️ +1.81 kB

Client Bundles (main, webpack, commons)

	vercel/next.js canary	vercel/next.js memory/leak-require-cache	Change
framework-HASH.js gzip	39.3 kB	39.3 kB	✓
main-HASH.js gzip	19.3 kB	19.3 kB	✓
webpack-HASH.js gzip	996 B	996 B	✓
Overall change	59.6 kB	59.6 kB	✓

Legacy Client Bundles (polyfills)

	vercel/next.js canary	vercel/next.js memory/leak-require-cache	Change
polyfills-HASH.js gzip	31.1 kB	31.1 kB	✓
Overall change	31.1 kB	31.1 kB	✓

Client Pages

	vercel/next.js canary	vercel/next.js memory/leak-require-cache	Change
_app-HASH.js gzip	1.02 kB	1.02 kB	✓
_error-HASH.js gzip	3.04 kB	3.04 kB	✓
amp-HASH.js gzip	526 B	526 B	✓
css-HASH.js gzip	334 B	334 B	✓
hooks-HASH.js gzip	890 B	890 B	✓
index-HASH.js gzip	262 B	262 B	✓
link-HASH.js gzip	1.65 kB	1.65 kB	✓
routerDirect..HASH.js gzip	331 B	331 B	✓
withRouter-HASH.js gzip	329 B	329 B	✓
99a142a5cfae..804.css gzip	125 B	125 B	✓
Overall change	8.51 kB	8.51 kB	✓

Client Build Manifests

	vercel/next.js canary	vercel/next.js memory/leak-require-cache	Change
_buildManifest.js gzip	393 B	393 B	✓
Overall change	393 B	393 B	✓

Serverless bundles Overall decrease ✓

	vercel/next.js canary	vercel/next.js memory/leak-require-cache	Change
_error.js	1.34 MB	1.34 MB	✓
404.html	2.42 kB	2.42 kB	✓
500.html	2.41 kB	2.41 kB	✓
amp.amp.html	10.8 kB	10.8 kB	✓
amp.html	1.61 kB	1.61 kB	✓
css.html	1.79 kB	1.79 kB	✓
hooks.html	1.67 kB	1.67 kB	✓
index.js	1.34 MB	1.34 MB	-2 B
link.js	1.4 MB	1.4 MB	⚠️ +2 B
routerDirect.js	1.39 MB	1.39 MB	-2 B
withRouter.js	1.39 MB	1.39 MB	-2 B
Overall change	6.9 MB	6.9 MB	-4 B

---

Webpack 4 Mode (Increase detected ⚠️)

General Overall increase ⚠️

	vercel/next.js canary	vercel/next.js memory/leak-require-cache	Change
buildDuration	11.6s	11.8s	⚠️ +237ms
buildDurationCached	4.9s	4.7s	-198ms
nodeModulesSize	46.6 MB	46.6 MB	⚠️ +1.81 kB

Page Load Tests Overall increase ✓

	vercel/next.js canary	vercel/next.js memory/leak-require-cache	Change
/ failed reqs	0	0	✓
/ total time (seconds)	2.323	2.308	-0.02
/ avg req/sec	1076.05	1083.36	+7.31
/error-in-render failed reqs	0	0	✓
/error-in-render total time (seconds)	1.226	1.224	0
/error-in-render avg req/sec	2039.41	2043.24	+3.83

Client Bundles (main, webpack, commons)

	vercel/next.js canary	vercel/next.js memory/leak-require-cache	Change
677f882d2ed8..HASH.js gzip	13.3 kB	13.3 kB	✓
framework.HASH.js gzip	39 kB	39 kB	✓
main-HASH.js gzip	7.19 kB	7.19 kB	✓
webpack-HASH.js gzip	751 B	751 B	✓
Overall change	60.2 kB	60.2 kB	✓

Legacy Client Bundles (polyfills)

	vercel/next.js canary	vercel/next.js memory/leak-require-cache	Change
polyfills-HASH.js gzip	31.3 kB	31.3 kB	✓
Overall change	31.3 kB	31.3 kB	✓

Client Pages

	vercel/next.js canary	vercel/next.js memory/leak-require-cache	Change
_app-HASH.js gzip	1.28 kB	1.28 kB	✓
_error-HASH.js gzip	3.71 kB	3.71 kB	✓
amp-HASH.js gzip	536 B	536 B	✓
css-HASH.js gzip	339 B	339 B	✓
hooks-HASH.js gzip	887 B	887 B	✓
index-HASH.js gzip	227 B	227 B	✓
link-HASH.js gzip	1.64 kB	1.64 kB	✓
routerDirect..HASH.js gzip	303 B	303 B	✓
withRouter-HASH.js gzip	302 B	302 B	✓
21c68fa65a48..217.css gzip	125 B	125 B	✓
Overall change	9.36 kB	9.36 kB	✓

Client Build Manifests

	vercel/next.js canary	vercel/next.js memory/leak-require-cache	Change
_buildManifest.js gzip	420 B	420 B	✓
Overall change	420 B	420 B	✓

Rendered Page Sizes

	vercel/next.js canary	vercel/next.js memory/leak-require-cache	Change
index.html gzip	613 B	613 B	✓
link.html gzip	620 B	620 B	✓
withRouter.html gzip	606 B	606 B	✓
Overall change	1.84 kB	1.84 kB	✓

Commit: 4dec3dd