[code-infra] Replace `fs-extra` with `node:fs` where possible #19127

bernardobelchior · 2025-08-11T10:12:50Z

Noticed that we depend on fs-extra, so tried to replace it with node:fs where possible. Most of the calls to fs-extra were node:fs calls anyway.

After these changes, there are only 4 imports of fs-extra, which we might be able to remove eventually.

bernardobelchior · 2025-08-11T10:12:59Z

docs/scripts/api/utils.ts

 import { Symbol, isPropertySignature, isExportSpecifier, TypeFormatFlags } from 'typescript';
+import fs from 'node:fs';


I imported from node:fs, but we seem to import from fs directly. I can change that if needed.

I'm adding mui/mui-public#476

mui-bot · 2025-08-11T10:14:17Z

Deploy preview: https://deploy-preview-19127--material-ui-x.netlify.app/

Bundle size report

Bundle	Parsed Size	Gzip Size
@mui/x-data-grid	0B^(0.00%)	0B^(0.00%)
@mui/x-data-grid-pro	0B^(0.00%)	🔺+2B^(0.00%)
@mui/x-data-grid-premium	0B^(0.00%)	🔺+2B^(0.00%)
@mui/x-charts	0B^(0.00%)	0B^(0.00%)
@mui/x-charts-pro	0B^(0.00%)	🔺+2B^(0.00%)
@mui/x-date-pickers	0B^(0.00%)	0B^(0.00%)
@mui/x-date-pickers-pro	0B^(0.00%)	🔺+5B^(+0.01%)
@mui/x-tree-view	0B^(0.00%)	0B^(0.00%)
@mui/x-tree-view-pro	0B^(0.00%)	🔺+1B^(0.00%)

Details of bundle changes

Generated by 🚫 dangerJS against bfb2539

bernardobelchior · 2025-08-11T10:27:39Z

scripts/releaseTag.mjs

@@ -50,7 +50,8 @@ async function main(argv) {
  const exec = dryRun ? execDry : execActual;

  const rootWorkspace = getWorkspaceRoot();
-  const rootWorkspaceManifest = await fse.readJSON(path.join(rootWorkspace, 'package.json'));


readJSON imports ./jsonfile, which imports the jsonfile package.

jsonfile's readFile is implemented here. Since we don't provide any options, it boils down to fs.readFile + JSON.parse(data, null).

stripBom just converts the buffer into an utf8 string, so this code is equivalent.

Janpot · 2025-08-11T10:34:37Z

docs/scripts/api/utils.ts

@@ -97,7 +97,7 @@ export async function writePrettifiedFile(filename: string, data: string) {
    );
  }

-  fse.writeFileSync(
+  fs.writeFileSync(


Why not

Suggested change

fs.writeFileSync(

await fs.writeFile(

Wanted to keep the changes to a minimum, but I guess this is fine.

Janpot · 2025-08-11T10:35:11Z

docs/scripts/api/utils.ts

 import { Symbol, isPropertySignature, isExportSpecifier, TypeFormatFlags } from 'typescript';
+import fs from 'node:fs';


Perhaps we can standardize on

Suggested change

import fs from 'node:fs';

import fs from 'node:fs/promises';

Yeah, I'm ok with that.

brijeshb42 · 2025-08-11T10:38:43Z

docs/scripts/formattedTSDemos.js

@@ -12,7 +12,6 @@
 const ignoreList = ['/pages.ts', 'styling.ts', 'styling.tsx', 'types.ts'];

 const fs = require('fs');


Might as well just import fs/promises instead of doing fs.promises

We have a mixed usage of fs and fs/promises in this file, so that's why I opted for this approach.

We can also do const fsPromises = require('fs/promises'); and migrate the relevant code snippets. What would you prefer?

Janpot · 2025-08-11T10:39:48Z

scripts/releaseTag.mjs

@@ -50,7 +50,8 @@ async function main(argv) {
  const exec = dryRun ? execDry : execActual;

  const rootWorkspace = getWorkspaceRoot();
-  const rootWorkspaceManifest = await fse.readJSON(path.join(rootWorkspace, 'package.json'));
+  const rootWorkspacePackageJson = await fs.readFile(path.join(rootWorkspace, 'package.json'));


I believe with a proper encoding it will always return a string

Suggested change

const rootWorkspacePackageJson = await fs.readFile(path.join(rootWorkspace, 'package.json'));

const rootWorkspacePackageJson = await fs.readFile(path.join(rootWorkspace, 'package.json'), 'utf-8');

You're right. If we do that, to maintain a 100% compatible change, we'd need to handle byte order mark as jsonfile does.

I'm not very familiar with this, so I'm not sure how big of a problem it might be.

From my tests, our root package.json does not use BOM, but it might be dependent on the last person who made changes to that specific file.

From the UTF-8 spec:

A protocol SHOULD forbid use of U+FEFF as a signature for those
textual protocol elements that the protocol mandates to be always
UTF-8, the signature function being totally useless in those
cases.

So I think we can ignore it and assume we're always using UTF-8

We've been consuming json files all over the place with this method since forever, so I'm not really concerned. I'm adding the unicode-bom rule in the ticket

bernardobelchior · 2025-08-11T12:48:22Z

docs/scripts/formattedTSDemos.js

@@ -90,15 +89,18 @@ const previewOverride = {
 async function transpileFile(tsxPath, program, ignoreCache = false) {
  const jsPath = tsxPath.replace(/\.tsx?$/, '.js');
  try {
-    if (!ignoreCache && (await fse.exists(jsPath))) {
-      const [jsStat, tsxStat] = await Promise.all([fse.stat(jsPath), fse.stat(tsxPath)]);
+    if (!ignoreCache && (await fs.promises.exists(jsPath))) {


This line introduced an issue. Fix here

[infra] Replace fs-extra with node:fs where possible

6e18dcd

bernardobelchior commented Aug 11, 2025

View reviewed changes

Replace readJSON

442b373

bernardobelchior commented Aug 11, 2025

View reviewed changes

bernardobelchior requested a review from a team August 11, 2025 10:29

bernardobelchior marked this pull request as ready for review August 11, 2025 10:29

Janpot reviewed Aug 11, 2025

View reviewed changes

Accept Jan's suggestion

a93786b

bernardobelchior requested a review from Janpot August 11, 2025 10:38

brijeshb42 reviewed Aug 11, 2025

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Janpot reviewed Aug 11, 2025

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Provide encoding

bfb2539

Janpot approved these changes Aug 11, 2025

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bernardobelchior requested a review from brijeshb42 August 11, 2025 12:07

brijeshb42 approved these changes Aug 11, 2025

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bernardobelchior merged commit 1947126 into mui:master Aug 11, 2025
20 checks passed

bernardobelchior deleted the replace-fs-extra-where-possible branch August 11, 2025 12:31

bernardobelchior mentioned this pull request Aug 11, 2025

[code-infra] Fix fs-extra removal from formattedTSDemos script #19132

Merged

bernardobelchior commented Aug 11, 2025

View reviewed changes

zannager added the scope: docs-infra Changes related to the docs-infra product. label Aug 11, 2025

Janpot added scope: code-infra Changes related to the core-infra product. and removed scope: docs-infra Changes related to the docs-infra product. labels Aug 11, 2025

This was referenced Aug 11, 2025

[code-infra] Replace fs-extra with node:fs mui/mui-public#481

Open

[code-infra] Fix fs.promises.watchFile #19151

Closed

oliviertassinari added the type: enhancement It’s an improvement, but we can’t make up our mind whether it's a bug fix or a new feature. label Aug 17, 2025

zannager changed the title ~~[infra] Replace fs-extra with node:fs where possible~~ [code-infra] Replace fs-extra with node:fs where possible Aug 18, 2025

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[code-infra] Replace `fs-extra` with `node:fs` where possible #19127

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		import { Symbol, isPropertySignature, isExportSpecifier, TypeFormatFlags } from 'typescript';
		import fs from 'node:fs';

		@@ -12,7 +12,6 @@
		const ignoreList = ['/pages.ts', 'styling.ts', 'styling.tsx', 'types.ts'];

		const fs = require('fs');

	const rootWorkspacePackageJson = await fs.readFile(path.join(rootWorkspace, 'package.json'));
	const rootWorkspacePackageJson = await fs.readFile(path.join(rootWorkspace, 'package.json'), 'utf-8');

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[code-infra] Replace `fs-extra` with `node:fs` where possible #19127

[code-infra] Replace `fs-extra` with `node:fs` where possible #19127

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