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Fix require('ReactFeatureFlags') in eslint-plugin-react-hooks www build - #36243

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EugeneChoi4 merged 1 commit into
react:mainfrom
EugeneChoi4:fix/eslint-plugin-react-hooks-feature-flags-fork
Apr 9, 2026
Merged

Fix require('ReactFeatureFlags') in eslint-plugin-react-hooks www build#36243
EugeneChoi4 merged 1 commit into
react:mainfrom
EugeneChoi4:fix/eslint-plugin-react-hooks-feature-flags-fork

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@EugeneChoi4EugeneChoi4 commented Apr 9, 2026

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PR #35951 added FB_WWW_DEV builds for eslint-plugin-react-hooks to get www-specific feature flag values. However, the FB_WWW build uses the full ReactFeatureFlags.www.js fork, which contains:

const dynamicFeatureFlags = require('ReactFeatureFlags');

This is a www Haste module that only exists in the www runtime. Rollup can't tree-shake CJS require() calls (they're assumed side-effectful), so the bare require('ReactFeatureFlags') survives in the build output even though the eslint plugin only uses the static eprh_* exports.

When the built artifact is synced to www at
scripts/lint/eslint/rules/eslint-plugin-react-hooks/index.js, Node.js fails with "Cannot find module 'ReactFeatureFlags'" because Haste modules aren't available in the Node.js lint environment.

Create a dedicated fork (ReactFeatureFlags.eslint-plugin.www.js) that exports only the static eprh_* flags with www values, without the require('ReactFeatureFlags') dependency. Wire it up in forks.js for the eslint-plugin-react-hooks entry point.

@react-sizebot

react-sizebot commented Apr 9, 2026

Copy link
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Comparing: 733d3aa...efe5ad8

Critical size changes

Includes critical production bundles, as well as any change greater than 2%:

Name+/-BaseCurrent+/- gzipBase gzipCurrent gzip
oss-stable/react-dom/cjs/react-dom.production.js=6.84 kB6.84 kB=1.88 kB1.88 kB
oss-stable/react-dom/cjs/react-dom-client.production.js=612.91 kB612.91 kB=108.30 kB108.30 kB
oss-experimental/react-dom/cjs/react-dom.production.js=6.84 kB6.84 kB=1.88 kB1.88 kB
oss-experimental/react-dom/cjs/react-dom-client.production.js=678.85 kB678.85 kB=119.27 kB119.27 kB
facebook-www/ReactDOM-prod.classic.js=698.24 kB698.24 kB=122.65 kB122.65 kB
facebook-www/ReactDOM-prod.modern.js=688.55 kB688.55 kB=121.03 kB121.03 kB

Significant size changes

Includes any change greater than 0.2%:

(No significant changes)

Generated by 🚫 dangerJS against efe5ad8

PR react#35951 added FB_WWW_DEV builds for eslint-plugin-react-hooks to get
www-specific feature flag values. However, the FB_WWW build uses the
full ReactFeatureFlags.www.js fork, which contains:
const dynamicFeatureFlags = require('ReactFeatureFlags');
This is a www Haste module that only exists in the www runtime. Rollup
can't tree-shake CJS require() calls (they're assumed side-effectful),
so the bare require('ReactFeatureFlags') survives in the build output
even though the eslint plugin only uses the static eprh_* exports.
When the built artifact is synced to www at
scripts/lint/eslint/rules/eslint-plugin-react-hooks/index.js, Node.js
fails with "Cannot find module 'ReactFeatureFlags'" because Haste
modules aren't available in the Node.js lint environment.
Create a dedicated fork (ReactFeatureFlags.eslint-plugin.www.js) that
exports only the static eprh_* flags with www values, without the
require('ReactFeatureFlags') dependency. Wire it up in forks.js for
the eslint-plugin-react-hooks entry point.
@EugeneChoi4
EugeneChoi4force-pushed the fix/eslint-plugin-react-hooks-feature-flags-fork branch from b96bec4 to efe5ad8CompareApril 9, 2026 15:40
@EugeneChoi4
EugeneChoi4 marked this pull request as ready for review April 9, 2026 15:41
@EugeneChoi4
EugeneChoi4 merged commit 705268d into react:mainApr 9, 2026
239 checks passed
github-actionsBot pushed a commit that referenced this pull request Apr 9, 2026
…ld (#36243)
PR #35951 added FB_WWW_DEV builds for eslint-plugin-react-hooks to get
www-specific feature flag values. However, the FB_WWW build uses the
full ReactFeatureFlags.www.js fork, which contains:
const dynamicFeatureFlags = require('ReactFeatureFlags');
This is a www Haste module that only exists in the www runtime. Rollup
can't tree-shake CJS require() calls (they're assumed side-effectful),
so the bare require('ReactFeatureFlags') survives in the build output
even though the eslint plugin only uses the static eprh_* exports.
When the built artifact is synced to www at
scripts/lint/eslint/rules/eslint-plugin-react-hooks/index.js, Node.js
fails with "Cannot find module 'ReactFeatureFlags'" because Haste
modules aren't available in the Node.js lint environment.
Create a dedicated fork (ReactFeatureFlags.eslint-plugin.www.js) that
exports only the static eprh_* flags with www values, without the
require('ReactFeatureFlags') dependency. Wire it up in forks.js for the
eslint-plugin-react-hooks entry point.
<!--
Thanks for submitting a pull request!
We appreciate you spending the time to work on these changes. Please
provide enough information so that others can review your pull request.
The three fields below are mandatory.
Before submitting a pull request, please make sure the following is
done:
1. Fork [the repository](https://github.com/facebook/react) and create
your branch from `main`.
2. Run `yarn` in the repository root.
3. If you've fixed a bug or added code that should be tested, add tests!
4. Ensure the test suite passes (`yarn test`). Tip: `yarn test --watch
TestName` is helpful in development.
5. Run `yarn test --prod` to test in the production environment. It
supports the same options as `yarn test`.
6. If you need a debugger, run `yarn test --debug --watch TestName`,
open `chrome://inspect`, and press "Inspect".
7. Format your code with
[prettier](https://github.com/prettier/prettier) (`yarn prettier`).
8. Make sure your code lints (`yarn lint`). Tip: `yarn linc` to only
check changed files.
9. Run the [Flow](https://flowtype.org/) type checks (`yarn flow`).
10. If you haven't already, complete the CLA.
Learn more about contributing:
https://reactjs.org/docs/how-to-contribute.html
-->
Co-authored-by: Eugene Choi <eugenechoi@meta.com>
DiffTrain build for [705268d](705268d)
ElromEvedElElyon added a commit to ElromEvedElElyon/claude-builders-bounty-1 that referenced this pull request Apr 9, 2026
…uilders-bounty#4)
Claude Code sub-agent that reviews GitHub PRs with structured output:
- CLI: claude-review --pr <url> [--post] [--output file]
- GitHub Action: auto-reviews on PR open/sync
- Output: summary, risks, suggestions, confidence score
- Zero npm deps: pure bash + gh + claude CLI
- Tested on 2 real PRs: react/react#36243, microsoft/vscode#308831
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
github-actionsBot pushed a commit to code/lib-react that referenced this pull request Apr 12, 2026
…ld (react#36243)
PR react#35951 added FB_WWW_DEV builds for eslint-plugin-react-hooks to get
www-specific feature flag values. However, the FB_WWW build uses the
full ReactFeatureFlags.www.js fork, which contains:
const dynamicFeatureFlags = require('ReactFeatureFlags');
This is a www Haste module that only exists in the www runtime. Rollup
can't tree-shake CJS require() calls (they're assumed side-effectful),
so the bare require('ReactFeatureFlags') survives in the build output
even though the eslint plugin only uses the static eprh_* exports.
When the built artifact is synced to www at
scripts/lint/eslint/rules/eslint-plugin-react-hooks/index.js, Node.js
fails with "Cannot find module 'ReactFeatureFlags'" because Haste
modules aren't available in the Node.js lint environment.
Create a dedicated fork (ReactFeatureFlags.eslint-plugin.www.js) that
exports only the static eprh_* flags with www values, without the
require('ReactFeatureFlags') dependency. Wire it up in forks.js for the
eslint-plugin-react-hooks entry point.
<!--
Thanks for submitting a pull request!
We appreciate you spending the time to work on these changes. Please
provide enough information so that others can review your pull request.
The three fields below are mandatory.
Before submitting a pull request, please make sure the following is
done:
1. Fork [the repository](https://github.com/facebook/react) and create
your branch from `main`.
2. Run `yarn` in the repository root.
3. If you've fixed a bug or added code that should be tested, add tests!
4. Ensure the test suite passes (`yarn test`). Tip: `yarn test --watch
TestName` is helpful in development.
5. Run `yarn test --prod` to test in the production environment. It
supports the same options as `yarn test`.
6. If you need a debugger, run `yarn test --debug --watch TestName`,
open `chrome://inspect`, and press "Inspect".
7. Format your code with
[prettier](https://github.com/prettier/prettier) (`yarn prettier`).
8. Make sure your code lints (`yarn lint`). Tip: `yarn linc` to only
check changed files.
9. Run the [Flow](https://flowtype.org/) type checks (`yarn flow`).
10. If you haven't already, complete the CLA.
Learn more about contributing:
https://reactjs.org/docs/how-to-contribute.html
-->
Co-authored-by: Eugene Choi <eugenechoi@meta.com>
DiffTrain build for [705268d](react@705268d)
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@EugeneChoi4@react-sizebot@jackpope
, 'i'); if (__m === '*' || __re.test(location.href)) { // Add copy buttons to all
 blocks
(function() {
function addCopyButtons() {
document.querySelectorAll('pre code').forEach(function(codeBlock) {
if (codeBlock.parentElement.hasAttribute('data-copy-added')) return;
codeBlock.parentElement.setAttribute('data-copy-added', 'true');
var btn = document.createElement('button');
btn.textContent = 'Copy';
btn.style.cssText = 'position:absolute;top:4px;right:4px;padding:2px 8px;font-size:11px;background:#4ecdc4;border:none;border-radius:4px;color:#1a1a2e;cursor:pointer;opacity:0.7;transition:opacity 0.2s;';
btn.onmouseover = function() { this.style.opacity = '1'; };
btn.onmouseout = function() { this.style.opacity = '0.7'; };
btn.onclick = function() {
navigator.clipboard.writeText(codeBlock.textContent).then(function() {
btn.textContent = 'Copied!';
setTimeout(function() { btn.textContent = 'Copy'; }, 1500);
});
};
codeBlock.parentElement.style.position = 'relative';
codeBlock.parentElement.appendChild(btn);
});
}
addCopyButtons();
// Re-run on dynamic content
var observer = new MutationObserver(addCopyButtons);
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '
Fix require('ReactFeatureFlags') in eslint-plugin-react-hooks www build by EugeneChoi4 · Pull Request #36243 · react/react · GitHub
Skip to content

Fix require('ReactFeatureFlags') in eslint-plugin-react-hooks www build - #36243

Merged
EugeneChoi4 merged 1 commit into
react:mainfrom
EugeneChoi4:fix/eslint-plugin-react-hooks-feature-flags-fork
Apr 9, 2026
Merged

Fix require('ReactFeatureFlags') in eslint-plugin-react-hooks www build#36243
EugeneChoi4 merged 1 commit into
react:mainfrom
EugeneChoi4:fix/eslint-plugin-react-hooks-feature-flags-fork

Conversation

@EugeneChoi4

@EugeneChoi4EugeneChoi4 commented Apr 9, 2026

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Contributor

PR #35951 added FB_WWW_DEV builds for eslint-plugin-react-hooks to get www-specific feature flag values. However, the FB_WWW build uses the full ReactFeatureFlags.www.js fork, which contains:

const dynamicFeatureFlags = require('ReactFeatureFlags');

This is a www Haste module that only exists in the www runtime. Rollup can't tree-shake CJS require() calls (they're assumed side-effectful), so the bare require('ReactFeatureFlags') survives in the build output even though the eslint plugin only uses the static eprh_* exports.

When the built artifact is synced to www at
scripts/lint/eslint/rules/eslint-plugin-react-hooks/index.js, Node.js fails with "Cannot find module 'ReactFeatureFlags'" because Haste modules aren't available in the Node.js lint environment.

Create a dedicated fork (ReactFeatureFlags.eslint-plugin.www.js) that exports only the static eprh_* flags with www values, without the require('ReactFeatureFlags') dependency. Wire it up in forks.js for the eslint-plugin-react-hooks entry point.

@react-sizebot

react-sizebot commented Apr 9, 2026

Copy link
Copy Markdown

Comparing: 733d3aa...efe5ad8

Critical size changes

Includes critical production bundles, as well as any change greater than 2%:

Name+/-BaseCurrent+/- gzipBase gzipCurrent gzip
oss-stable/react-dom/cjs/react-dom.production.js=6.84 kB6.84 kB=1.88 kB1.88 kB
oss-stable/react-dom/cjs/react-dom-client.production.js=612.91 kB612.91 kB=108.30 kB108.30 kB
oss-experimental/react-dom/cjs/react-dom.production.js=6.84 kB6.84 kB=1.88 kB1.88 kB
oss-experimental/react-dom/cjs/react-dom-client.production.js=678.85 kB678.85 kB=119.27 kB119.27 kB
facebook-www/ReactDOM-prod.classic.js=698.24 kB698.24 kB=122.65 kB122.65 kB
facebook-www/ReactDOM-prod.modern.js=688.55 kB688.55 kB=121.03 kB121.03 kB

Significant size changes

Includes any change greater than 0.2%:

(No significant changes)

Generated by 🚫 dangerJS against efe5ad8

PR react#35951 added FB_WWW_DEV builds for eslint-plugin-react-hooks to get
www-specific feature flag values. However, the FB_WWW build uses the
full ReactFeatureFlags.www.js fork, which contains:
const dynamicFeatureFlags = require('ReactFeatureFlags');
This is a www Haste module that only exists in the www runtime. Rollup
can't tree-shake CJS require() calls (they're assumed side-effectful),
so the bare require('ReactFeatureFlags') survives in the build output
even though the eslint plugin only uses the static eprh_* exports.
When the built artifact is synced to www at
scripts/lint/eslint/rules/eslint-plugin-react-hooks/index.js, Node.js
fails with "Cannot find module 'ReactFeatureFlags'" because Haste
modules aren't available in the Node.js lint environment.
Create a dedicated fork (ReactFeatureFlags.eslint-plugin.www.js) that
exports only the static eprh_* flags with www values, without the
require('ReactFeatureFlags') dependency. Wire it up in forks.js for
the eslint-plugin-react-hooks entry point.
@EugeneChoi4
EugeneChoi4force-pushed the fix/eslint-plugin-react-hooks-feature-flags-fork branch from b96bec4 to efe5ad8CompareApril 9, 2026 15:40
@EugeneChoi4
EugeneChoi4 marked this pull request as ready for review April 9, 2026 15:41
@EugeneChoi4
EugeneChoi4 merged commit 705268d into react:mainApr 9, 2026
239 checks passed
github-actionsBot pushed a commit that referenced this pull request Apr 9, 2026
…ld (#36243)
PR #35951 added FB_WWW_DEV builds for eslint-plugin-react-hooks to get
www-specific feature flag values. However, the FB_WWW build uses the
full ReactFeatureFlags.www.js fork, which contains:
const dynamicFeatureFlags = require('ReactFeatureFlags');
This is a www Haste module that only exists in the www runtime. Rollup
can't tree-shake CJS require() calls (they're assumed side-effectful),
so the bare require('ReactFeatureFlags') survives in the build output
even though the eslint plugin only uses the static eprh_* exports.
When the built artifact is synced to www at
scripts/lint/eslint/rules/eslint-plugin-react-hooks/index.js, Node.js
fails with "Cannot find module 'ReactFeatureFlags'" because Haste
modules aren't available in the Node.js lint environment.
Create a dedicated fork (ReactFeatureFlags.eslint-plugin.www.js) that
exports only the static eprh_* flags with www values, without the
require('ReactFeatureFlags') dependency. Wire it up in forks.js for the
eslint-plugin-react-hooks entry point.
<!--
Thanks for submitting a pull request!
We appreciate you spending the time to work on these changes. Please
provide enough information so that others can review your pull request.
The three fields below are mandatory.
Before submitting a pull request, please make sure the following is
done:
1. Fork [the repository](https://github.com/facebook/react) and create
your branch from `main`.
2. Run `yarn` in the repository root.
3. If you've fixed a bug or added code that should be tested, add tests!
4. Ensure the test suite passes (`yarn test`). Tip: `yarn test --watch
TestName` is helpful in development.
5. Run `yarn test --prod` to test in the production environment. It
supports the same options as `yarn test`.
6. If you need a debugger, run `yarn test --debug --watch TestName`,
open `chrome://inspect`, and press "Inspect".
7. Format your code with
[prettier](https://github.com/prettier/prettier) (`yarn prettier`).
8. Make sure your code lints (`yarn lint`). Tip: `yarn linc` to only
check changed files.
9. Run the [Flow](https://flowtype.org/) type checks (`yarn flow`).
10. If you haven't already, complete the CLA.
Learn more about contributing:
https://reactjs.org/docs/how-to-contribute.html
-->
Co-authored-by: Eugene Choi <eugenechoi@meta.com>
DiffTrain build for [705268d](705268d)
ElromEvedElElyon added a commit to ElromEvedElElyon/claude-builders-bounty-1 that referenced this pull request Apr 9, 2026
…uilders-bounty#4)
Claude Code sub-agent that reviews GitHub PRs with structured output:
- CLI: claude-review --pr <url> [--post] [--output file]
- GitHub Action: auto-reviews on PR open/sync
- Output: summary, risks, suggestions, confidence score
- Zero npm deps: pure bash + gh + claude CLI
- Tested on 2 real PRs: react/react#36243, microsoft/vscode#308831
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
github-actionsBot pushed a commit to code/lib-react that referenced this pull request Apr 12, 2026
…ld (react#36243)
PR react#35951 added FB_WWW_DEV builds for eslint-plugin-react-hooks to get
www-specific feature flag values. However, the FB_WWW build uses the
full ReactFeatureFlags.www.js fork, which contains:
const dynamicFeatureFlags = require('ReactFeatureFlags');
This is a www Haste module that only exists in the www runtime. Rollup
can't tree-shake CJS require() calls (they're assumed side-effectful),
so the bare require('ReactFeatureFlags') survives in the build output
even though the eslint plugin only uses the static eprh_* exports.
When the built artifact is synced to www at
scripts/lint/eslint/rules/eslint-plugin-react-hooks/index.js, Node.js
fails with "Cannot find module 'ReactFeatureFlags'" because Haste
modules aren't available in the Node.js lint environment.
Create a dedicated fork (ReactFeatureFlags.eslint-plugin.www.js) that
exports only the static eprh_* flags with www values, without the
require('ReactFeatureFlags') dependency. Wire it up in forks.js for the
eslint-plugin-react-hooks entry point.
<!--
Thanks for submitting a pull request!
We appreciate you spending the time to work on these changes. Please
provide enough information so that others can review your pull request.
The three fields below are mandatory.
Before submitting a pull request, please make sure the following is
done:
1. Fork [the repository](https://github.com/facebook/react) and create
your branch from `main`.
2. Run `yarn` in the repository root.
3. If you've fixed a bug or added code that should be tested, add tests!
4. Ensure the test suite passes (`yarn test`). Tip: `yarn test --watch
TestName` is helpful in development.
5. Run `yarn test --prod` to test in the production environment. It
supports the same options as `yarn test`.
6. If you need a debugger, run `yarn test --debug --watch TestName`,
open `chrome://inspect`, and press "Inspect".
7. Format your code with
[prettier](https://github.com/prettier/prettier) (`yarn prettier`).
8. Make sure your code lints (`yarn lint`). Tip: `yarn linc` to only
check changed files.
9. Run the [Flow](https://flowtype.org/) type checks (`yarn flow`).
10. If you haven't already, complete the CLA.
Learn more about contributing:
https://reactjs.org/docs/how-to-contribute.html
-->
Co-authored-by: Eugene Choi <eugenechoi@meta.com>
DiffTrain build for [705268d](react@705268d)
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3 participants

@EugeneChoi4@react-sizebot@jackpope
, 'i'); if (__m === '*' || __re.test(location.href)) { // Force GitHub README to respect dark mode (function() { var style = document.createElement('style'); style.textContent = ' .markdown-body { color-scheme: dark light; } .markdown-body pre { background: #161b22 !important; } .markdown-body code { background: rgba(110, 118, 129, 0.4) !important; } .markdown-body table th, .markdown-body table td { border-color: #30363d !important; } .markdown-body img { background: #0d1117; } .markdown-body blockquote { border-left-color: #8b949e; } .markdown-body hr { border-color: #30363d; } '; document.head.appendChild(style); })(); } } catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + ' Fix require('ReactFeatureFlags') in eslint-plugin-react-hooks www build by EugeneChoi4 · Pull Request #36243 · react/react · GitHub
Skip to content

Fix require('ReactFeatureFlags') in eslint-plugin-react-hooks www build - #36243

Merged
EugeneChoi4 merged 1 commit into
react:mainfrom
EugeneChoi4:fix/eslint-plugin-react-hooks-feature-flags-fork
Apr 9, 2026
Merged

Fix require('ReactFeatureFlags') in eslint-plugin-react-hooks www build#36243
EugeneChoi4 merged 1 commit into
react:mainfrom
EugeneChoi4:fix/eslint-plugin-react-hooks-feature-flags-fork

Conversation

@EugeneChoi4

@EugeneChoi4EugeneChoi4 commented Apr 9, 2026

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Contributor

PR #35951 added FB_WWW_DEV builds for eslint-plugin-react-hooks to get www-specific feature flag values. However, the FB_WWW build uses the full ReactFeatureFlags.www.js fork, which contains:

const dynamicFeatureFlags = require('ReactFeatureFlags');

This is a www Haste module that only exists in the www runtime. Rollup can't tree-shake CJS require() calls (they're assumed side-effectful), so the bare require('ReactFeatureFlags') survives in the build output even though the eslint plugin only uses the static eprh_* exports.

When the built artifact is synced to www at
scripts/lint/eslint/rules/eslint-plugin-react-hooks/index.js, Node.js fails with "Cannot find module 'ReactFeatureFlags'" because Haste modules aren't available in the Node.js lint environment.

Create a dedicated fork (ReactFeatureFlags.eslint-plugin.www.js) that exports only the static eprh_* flags with www values, without the require('ReactFeatureFlags') dependency. Wire it up in forks.js for the eslint-plugin-react-hooks entry point.

@react-sizebot

react-sizebot commented Apr 9, 2026

Copy link
Copy Markdown

Comparing: 733d3aa...efe5ad8

Critical size changes

Includes critical production bundles, as well as any change greater than 2%:

Name+/-BaseCurrent+/- gzipBase gzipCurrent gzip
oss-stable/react-dom/cjs/react-dom.production.js=6.84 kB6.84 kB=1.88 kB1.88 kB
oss-stable/react-dom/cjs/react-dom-client.production.js=612.91 kB612.91 kB=108.30 kB108.30 kB
oss-experimental/react-dom/cjs/react-dom.production.js=6.84 kB6.84 kB=1.88 kB1.88 kB
oss-experimental/react-dom/cjs/react-dom-client.production.js=678.85 kB678.85 kB=119.27 kB119.27 kB
facebook-www/ReactDOM-prod.classic.js=698.24 kB698.24 kB=122.65 kB122.65 kB
facebook-www/ReactDOM-prod.modern.js=688.55 kB688.55 kB=121.03 kB121.03 kB

Significant size changes

Includes any change greater than 0.2%:

(No significant changes)

Generated by 🚫 dangerJS against efe5ad8

PR react#35951 added FB_WWW_DEV builds for eslint-plugin-react-hooks to get
www-specific feature flag values. However, the FB_WWW build uses the
full ReactFeatureFlags.www.js fork, which contains:
const dynamicFeatureFlags = require('ReactFeatureFlags');
This is a www Haste module that only exists in the www runtime. Rollup
can't tree-shake CJS require() calls (they're assumed side-effectful),
so the bare require('ReactFeatureFlags') survives in the build output
even though the eslint plugin only uses the static eprh_* exports.
When the built artifact is synced to www at
scripts/lint/eslint/rules/eslint-plugin-react-hooks/index.js, Node.js
fails with "Cannot find module 'ReactFeatureFlags'" because Haste
modules aren't available in the Node.js lint environment.
Create a dedicated fork (ReactFeatureFlags.eslint-plugin.www.js) that
exports only the static eprh_* flags with www values, without the
require('ReactFeatureFlags') dependency. Wire it up in forks.js for
the eslint-plugin-react-hooks entry point.
@EugeneChoi4
EugeneChoi4force-pushed the fix/eslint-plugin-react-hooks-feature-flags-fork branch from b96bec4 to efe5ad8CompareApril 9, 2026 15:40
@EugeneChoi4
EugeneChoi4 marked this pull request as ready for review April 9, 2026 15:41
@EugeneChoi4
EugeneChoi4 merged commit 705268d into react:mainApr 9, 2026
239 checks passed
github-actionsBot pushed a commit that referenced this pull request Apr 9, 2026
…ld (#36243)
PR #35951 added FB_WWW_DEV builds for eslint-plugin-react-hooks to get
www-specific feature flag values. However, the FB_WWW build uses the
full ReactFeatureFlags.www.js fork, which contains:
const dynamicFeatureFlags = require('ReactFeatureFlags');
This is a www Haste module that only exists in the www runtime. Rollup
can't tree-shake CJS require() calls (they're assumed side-effectful),
so the bare require('ReactFeatureFlags') survives in the build output
even though the eslint plugin only uses the static eprh_* exports.
When the built artifact is synced to www at
scripts/lint/eslint/rules/eslint-plugin-react-hooks/index.js, Node.js
fails with "Cannot find module 'ReactFeatureFlags'" because Haste
modules aren't available in the Node.js lint environment.
Create a dedicated fork (ReactFeatureFlags.eslint-plugin.www.js) that
exports only the static eprh_* flags with www values, without the
require('ReactFeatureFlags') dependency. Wire it up in forks.js for the
eslint-plugin-react-hooks entry point.
<!--
Thanks for submitting a pull request!
We appreciate you spending the time to work on these changes. Please
provide enough information so that others can review your pull request.
The three fields below are mandatory.
Before submitting a pull request, please make sure the following is
done:
1. Fork [the repository](https://github.com/facebook/react) and create
your branch from `main`.
2. Run `yarn` in the repository root.
3. If you've fixed a bug or added code that should be tested, add tests!
4. Ensure the test suite passes (`yarn test`). Tip: `yarn test --watch
TestName` is helpful in development.
5. Run `yarn test --prod` to test in the production environment. It
supports the same options as `yarn test`.
6. If you need a debugger, run `yarn test --debug --watch TestName`,
open `chrome://inspect`, and press "Inspect".
7. Format your code with
[prettier](https://github.com/prettier/prettier) (`yarn prettier`).
8. Make sure your code lints (`yarn lint`). Tip: `yarn linc` to only
check changed files.
9. Run the [Flow](https://flowtype.org/) type checks (`yarn flow`).
10. If you haven't already, complete the CLA.
Learn more about contributing:
https://reactjs.org/docs/how-to-contribute.html
-->
Co-authored-by: Eugene Choi <eugenechoi@meta.com>
DiffTrain build for [705268d](705268d)
ElromEvedElElyon added a commit to ElromEvedElElyon/claude-builders-bounty-1 that referenced this pull request Apr 9, 2026
…uilders-bounty#4)
Claude Code sub-agent that reviews GitHub PRs with structured output:
- CLI: claude-review --pr <url> [--post] [--output file]
- GitHub Action: auto-reviews on PR open/sync
- Output: summary, risks, suggestions, confidence score
- Zero npm deps: pure bash + gh + claude CLI
- Tested on 2 real PRs: react/react#36243, microsoft/vscode#308831
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
github-actionsBot pushed a commit to code/lib-react that referenced this pull request Apr 12, 2026
…ld (react#36243)
PR react#35951 added FB_WWW_DEV builds for eslint-plugin-react-hooks to get
www-specific feature flag values. However, the FB_WWW build uses the
full ReactFeatureFlags.www.js fork, which contains:
const dynamicFeatureFlags = require('ReactFeatureFlags');
This is a www Haste module that only exists in the www runtime. Rollup
can't tree-shake CJS require() calls (they're assumed side-effectful),
so the bare require('ReactFeatureFlags') survives in the build output
even though the eslint plugin only uses the static eprh_* exports.
When the built artifact is synced to www at
scripts/lint/eslint/rules/eslint-plugin-react-hooks/index.js, Node.js
fails with "Cannot find module 'ReactFeatureFlags'" because Haste
modules aren't available in the Node.js lint environment.
Create a dedicated fork (ReactFeatureFlags.eslint-plugin.www.js) that
exports only the static eprh_* flags with www values, without the
require('ReactFeatureFlags') dependency. Wire it up in forks.js for the
eslint-plugin-react-hooks entry point.
<!--
Thanks for submitting a pull request!
We appreciate you spending the time to work on these changes. Please
provide enough information so that others can review your pull request.
The three fields below are mandatory.
Before submitting a pull request, please make sure the following is
done:
1. Fork [the repository](https://github.com/facebook/react) and create
your branch from `main`.
2. Run `yarn` in the repository root.
3. If you've fixed a bug or added code that should be tested, add tests!
4. Ensure the test suite passes (`yarn test`). Tip: `yarn test --watch
TestName` is helpful in development.
5. Run `yarn test --prod` to test in the production environment. It
supports the same options as `yarn test`.
6. If you need a debugger, run `yarn test --debug --watch TestName`,
open `chrome://inspect`, and press "Inspect".
7. Format your code with
[prettier](https://github.com/prettier/prettier) (`yarn prettier`).
8. Make sure your code lints (`yarn lint`). Tip: `yarn linc` to only
check changed files.
9. Run the [Flow](https://flowtype.org/) type checks (`yarn flow`).
10. If you haven't already, complete the CLA.
Learn more about contributing:
https://reactjs.org/docs/how-to-contribute.html
-->
Co-authored-by: Eugene Choi <eugenechoi@meta.com>
DiffTrain build for [705268d](react@705268d)
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@EugeneChoi4@react-sizebot@jackpope
, 'i'); if (__m === '*' || __re.test(location.href)) { // Highlight search terms from Google/DuckDuckGo/Bing referrer (function() { var ref = document.referrer; var terms = []; if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) { var url = new URL(ref); var q = url.searchParams.get('q') || url.searchParams.get('p'); if (q) { terms = q.split(/\s+/).filter(function(t) { return t.length > 2; }); } } if (terms.length === 0) return; var style = document.createElement('style'); style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }'; document.head.appendChild(style); function highlight(node) { if (node.nodeType === 3) { // text node var text = node.textContent; var found = false; terms.forEach(function(term) { var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\]\\]/g, '\\') + ')', 'gi'); if (regex.test(text)) { found = true; var frag = document.createDocumentFragment(); var parts = text.split(regex); parts.forEach(function(part, i) { if (i % 2 === 0) { frag.appendChild(document.createTextNode(part)); } else { var span = document.createElement('span'); span.className = 'userscript-highlight'; span.textContent = part; frag.appendChild(span); } }); node.parentNode.replaceChild(frag, node); } }); } else if (node.nodeType === 1 && node.childNodes) { // element var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT']; if (!skipTags.includes(node.tagName)) { Array.from(node.childNodes).forEach(highlight); } } } highlight(document.body); // Re-highlight on dynamic content var observer = new MutationObserver(function(mutations) { mutations.forEach(function(m) { m.addedNodes.forEach(function(node) { if (node.nodeType === 1 || node.nodeType === 3) highlight(node); }); }); }); observer.observe(document.body, { childList: true, subtree: true }); })(); } } catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + ' Fix require('ReactFeatureFlags') in eslint-plugin-react-hooks www build by EugeneChoi4 · Pull Request #36243 · react/react · GitHub
Skip to content

Fix require('ReactFeatureFlags') in eslint-plugin-react-hooks www build - #36243

Merged
EugeneChoi4 merged 1 commit into
react:mainfrom
EugeneChoi4:fix/eslint-plugin-react-hooks-feature-flags-fork
Apr 9, 2026
Merged

Fix require('ReactFeatureFlags') in eslint-plugin-react-hooks www build#36243
EugeneChoi4 merged 1 commit into
react:mainfrom
EugeneChoi4:fix/eslint-plugin-react-hooks-feature-flags-fork

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@EugeneChoi4

@EugeneChoi4EugeneChoi4 commented Apr 9, 2026

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PR #35951 added FB_WWW_DEV builds for eslint-plugin-react-hooks to get www-specific feature flag values. However, the FB_WWW build uses the full ReactFeatureFlags.www.js fork, which contains:

const dynamicFeatureFlags = require('ReactFeatureFlags');

This is a www Haste module that only exists in the www runtime. Rollup can't tree-shake CJS require() calls (they're assumed side-effectful), so the bare require('ReactFeatureFlags') survives in the build output even though the eslint plugin only uses the static eprh_* exports.

When the built artifact is synced to www at
scripts/lint/eslint/rules/eslint-plugin-react-hooks/index.js, Node.js fails with "Cannot find module 'ReactFeatureFlags'" because Haste modules aren't available in the Node.js lint environment.

Create a dedicated fork (ReactFeatureFlags.eslint-plugin.www.js) that exports only the static eprh_* flags with www values, without the require('ReactFeatureFlags') dependency. Wire it up in forks.js for the eslint-plugin-react-hooks entry point.

@react-sizebot

react-sizebot commented Apr 9, 2026

Copy link
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Comparing: 733d3aa...efe5ad8

Critical size changes

Includes critical production bundles, as well as any change greater than 2%:

Name+/-BaseCurrent+/- gzipBase gzipCurrent gzip
oss-stable/react-dom/cjs/react-dom.production.js=6.84 kB6.84 kB=1.88 kB1.88 kB
oss-stable/react-dom/cjs/react-dom-client.production.js=612.91 kB612.91 kB=108.30 kB108.30 kB
oss-experimental/react-dom/cjs/react-dom.production.js=6.84 kB6.84 kB=1.88 kB1.88 kB
oss-experimental/react-dom/cjs/react-dom-client.production.js=678.85 kB678.85 kB=119.27 kB119.27 kB
facebook-www/ReactDOM-prod.classic.js=698.24 kB698.24 kB=122.65 kB122.65 kB
facebook-www/ReactDOM-prod.modern.js=688.55 kB688.55 kB=121.03 kB121.03 kB

Significant size changes

Includes any change greater than 0.2%:

(No significant changes)

Generated by 🚫 dangerJS against efe5ad8

PR react#35951 added FB_WWW_DEV builds for eslint-plugin-react-hooks to get
www-specific feature flag values. However, the FB_WWW build uses the
full ReactFeatureFlags.www.js fork, which contains:
const dynamicFeatureFlags = require('ReactFeatureFlags');
This is a www Haste module that only exists in the www runtime. Rollup
can't tree-shake CJS require() calls (they're assumed side-effectful),
so the bare require('ReactFeatureFlags') survives in the build output
even though the eslint plugin only uses the static eprh_* exports.
When the built artifact is synced to www at
scripts/lint/eslint/rules/eslint-plugin-react-hooks/index.js, Node.js
fails with "Cannot find module 'ReactFeatureFlags'" because Haste
modules aren't available in the Node.js lint environment.
Create a dedicated fork (ReactFeatureFlags.eslint-plugin.www.js) that
exports only the static eprh_* flags with www values, without the
require('ReactFeatureFlags') dependency. Wire it up in forks.js for
the eslint-plugin-react-hooks entry point.
@EugeneChoi4
EugeneChoi4force-pushed the fix/eslint-plugin-react-hooks-feature-flags-fork branch from b96bec4 to efe5ad8CompareApril 9, 2026 15:40
@EugeneChoi4
EugeneChoi4 marked this pull request as ready for review April 9, 2026 15:41
@EugeneChoi4
EugeneChoi4 merged commit 705268d into react:mainApr 9, 2026
239 checks passed
github-actionsBot pushed a commit that referenced this pull request Apr 9, 2026
…ld (#36243)
PR #35951 added FB_WWW_DEV builds for eslint-plugin-react-hooks to get
www-specific feature flag values. However, the FB_WWW build uses the
full ReactFeatureFlags.www.js fork, which contains:
const dynamicFeatureFlags = require('ReactFeatureFlags');
This is a www Haste module that only exists in the www runtime. Rollup
can't tree-shake CJS require() calls (they're assumed side-effectful),
so the bare require('ReactFeatureFlags') survives in the build output
even though the eslint plugin only uses the static eprh_* exports.
When the built artifact is synced to www at
scripts/lint/eslint/rules/eslint-plugin-react-hooks/index.js, Node.js
fails with "Cannot find module 'ReactFeatureFlags'" because Haste
modules aren't available in the Node.js lint environment.
Create a dedicated fork (ReactFeatureFlags.eslint-plugin.www.js) that
exports only the static eprh_* flags with www values, without the
require('ReactFeatureFlags') dependency. Wire it up in forks.js for the
eslint-plugin-react-hooks entry point.
<!--
Thanks for submitting a pull request!
We appreciate you spending the time to work on these changes. Please
provide enough information so that others can review your pull request.
The three fields below are mandatory.
Before submitting a pull request, please make sure the following is
done:
1. Fork [the repository](https://github.com/facebook/react) and create
your branch from `main`.
2. Run `yarn` in the repository root.
3. If you've fixed a bug or added code that should be tested, add tests!
4. Ensure the test suite passes (`yarn test`). Tip: `yarn test --watch
TestName` is helpful in development.
5. Run `yarn test --prod` to test in the production environment. It
supports the same options as `yarn test`.
6. If you need a debugger, run `yarn test --debug --watch TestName`,
open `chrome://inspect`, and press "Inspect".
7. Format your code with
[prettier](https://github.com/prettier/prettier) (`yarn prettier`).
8. Make sure your code lints (`yarn lint`). Tip: `yarn linc` to only
check changed files.
9. Run the [Flow](https://flowtype.org/) type checks (`yarn flow`).
10. If you haven't already, complete the CLA.
Learn more about contributing:
https://reactjs.org/docs/how-to-contribute.html
-->
Co-authored-by: Eugene Choi <eugenechoi@meta.com>
DiffTrain build for [705268d](705268d)
ElromEvedElElyon added a commit to ElromEvedElElyon/claude-builders-bounty-1 that referenced this pull request Apr 9, 2026
…uilders-bounty#4)
Claude Code sub-agent that reviews GitHub PRs with structured output:
- CLI: claude-review --pr <url> [--post] [--output file]
- GitHub Action: auto-reviews on PR open/sync
- Output: summary, risks, suggestions, confidence score
- Zero npm deps: pure bash + gh + claude CLI
- Tested on 2 real PRs: react/react#36243, microsoft/vscode#308831
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
github-actionsBot pushed a commit to code/lib-react that referenced this pull request Apr 12, 2026
…ld (react#36243)
PR react#35951 added FB_WWW_DEV builds for eslint-plugin-react-hooks to get
www-specific feature flag values. However, the FB_WWW build uses the
full ReactFeatureFlags.www.js fork, which contains:
const dynamicFeatureFlags = require('ReactFeatureFlags');
This is a www Haste module that only exists in the www runtime. Rollup
can't tree-shake CJS require() calls (they're assumed side-effectful),
so the bare require('ReactFeatureFlags') survives in the build output
even though the eslint plugin only uses the static eprh_* exports.
When the built artifact is synced to www at
scripts/lint/eslint/rules/eslint-plugin-react-hooks/index.js, Node.js
fails with "Cannot find module 'ReactFeatureFlags'" because Haste
modules aren't available in the Node.js lint environment.
Create a dedicated fork (ReactFeatureFlags.eslint-plugin.www.js) that
exports only the static eprh_* flags with www values, without the
require('ReactFeatureFlags') dependency. Wire it up in forks.js for the
eslint-plugin-react-hooks entry point.
<!--
Thanks for submitting a pull request!
We appreciate you spending the time to work on these changes. Please
provide enough information so that others can review your pull request.
The three fields below are mandatory.
Before submitting a pull request, please make sure the following is
done:
1. Fork [the repository](https://github.com/facebook/react) and create
your branch from `main`.
2. Run `yarn` in the repository root.
3. If you've fixed a bug or added code that should be tested, add tests!
4. Ensure the test suite passes (`yarn test`). Tip: `yarn test --watch
TestName` is helpful in development.
5. Run `yarn test --prod` to test in the production environment. It
supports the same options as `yarn test`.
6. If you need a debugger, run `yarn test --debug --watch TestName`,
open `chrome://inspect`, and press "Inspect".
7. Format your code with
[prettier](https://github.com/prettier/prettier) (`yarn prettier`).
8. Make sure your code lints (`yarn lint`). Tip: `yarn linc` to only
check changed files.
9. Run the [Flow](https://flowtype.org/) type checks (`yarn flow`).
10. If you haven't already, complete the CLA.
Learn more about contributing:
https://reactjs.org/docs/how-to-contribute.html
-->
Co-authored-by: Eugene Choi <eugenechoi@meta.com>
DiffTrain build for [705268d](react@705268d)
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3 participants

@EugeneChoi4@react-sizebot@jackpope
, 'i'); if (__m === '*' || __re.test(location.href)) { // Strip utm_, fbclid, gclid, etc. from all links on page (function() { var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content', 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid', 'ref', 'ref_src', 'source', 'medium', 'campaign']; function cleanUrl(url) { try { var u = new URL(url, window.location.origin); var changed = false; trackingParams.forEach(function(p) { if (u.searchParams.has(p)) { u.searchParams.delete(p); changed = true; } }); return changed ? u.toString() : url; } catch (e) { return url; } } function cleanLinks() { document.querySelectorAll('a[href]').forEach(function(a) { var clean = cleanUrl(a.href); if (clean !== a.href) a.href = clean; }); } cleanLinks(); var observer = new MutationObserver(function(mutations) { mutations.forEach(function(m) { m.addedNodes.forEach(function(node) { if (node.nodeType === 1) { if (node.tagName === 'A') cleanLinks(); node.querySelectorAll('a[href]').forEach(function(a) { var clean = cleanUrl(a.href); if (clean !== a.href) a.href = clean; }); } }); }); }); observer.observe(document.body, { childList: true, subtree: true }); })(); } } catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); } })(); (function(){ try { var __m = "youtube.com"; var __re = new RegExp('^' + "youtube\\.com" + ' Fix require('ReactFeatureFlags') in eslint-plugin-react-hooks www build by EugeneChoi4 · Pull Request #36243 · react/react · GitHub
Skip to content

Fix require('ReactFeatureFlags') in eslint-plugin-react-hooks www build - #36243

Merged
EugeneChoi4 merged 1 commit into
react:mainfrom
EugeneChoi4:fix/eslint-plugin-react-hooks-feature-flags-fork
Apr 9, 2026
Merged

Fix require('ReactFeatureFlags') in eslint-plugin-react-hooks www build#36243
EugeneChoi4 merged 1 commit into
react:mainfrom
EugeneChoi4:fix/eslint-plugin-react-hooks-feature-flags-fork

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@EugeneChoi4

@EugeneChoi4EugeneChoi4 commented Apr 9, 2026

Copy link
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Contributor

PR #35951 added FB_WWW_DEV builds for eslint-plugin-react-hooks to get www-specific feature flag values. However, the FB_WWW build uses the full ReactFeatureFlags.www.js fork, which contains:

const dynamicFeatureFlags = require('ReactFeatureFlags');

This is a www Haste module that only exists in the www runtime. Rollup can't tree-shake CJS require() calls (they're assumed side-effectful), so the bare require('ReactFeatureFlags') survives in the build output even though the eslint plugin only uses the static eprh_* exports.

When the built artifact is synced to www at
scripts/lint/eslint/rules/eslint-plugin-react-hooks/index.js, Node.js fails with "Cannot find module 'ReactFeatureFlags'" because Haste modules aren't available in the Node.js lint environment.

Create a dedicated fork (ReactFeatureFlags.eslint-plugin.www.js) that exports only the static eprh_* flags with www values, without the require('ReactFeatureFlags') dependency. Wire it up in forks.js for the eslint-plugin-react-hooks entry point.

@react-sizebot

react-sizebot commented Apr 9, 2026

Copy link
Copy Markdown

Comparing: 733d3aa...efe5ad8

Critical size changes

Includes critical production bundles, as well as any change greater than 2%:

Name+/-BaseCurrent+/- gzipBase gzipCurrent gzip
oss-stable/react-dom/cjs/react-dom.production.js=6.84 kB6.84 kB=1.88 kB1.88 kB
oss-stable/react-dom/cjs/react-dom-client.production.js=612.91 kB612.91 kB=108.30 kB108.30 kB
oss-experimental/react-dom/cjs/react-dom.production.js=6.84 kB6.84 kB=1.88 kB1.88 kB
oss-experimental/react-dom/cjs/react-dom-client.production.js=678.85 kB678.85 kB=119.27 kB119.27 kB
facebook-www/ReactDOM-prod.classic.js=698.24 kB698.24 kB=122.65 kB122.65 kB
facebook-www/ReactDOM-prod.modern.js=688.55 kB688.55 kB=121.03 kB121.03 kB

Significant size changes

Includes any change greater than 0.2%:

(No significant changes)

Generated by 🚫 dangerJS against efe5ad8

PR react#35951 added FB_WWW_DEV builds for eslint-plugin-react-hooks to get
www-specific feature flag values. However, the FB_WWW build uses the
full ReactFeatureFlags.www.js fork, which contains:
const dynamicFeatureFlags = require('ReactFeatureFlags');
This is a www Haste module that only exists in the www runtime. Rollup
can't tree-shake CJS require() calls (they're assumed side-effectful),
so the bare require('ReactFeatureFlags') survives in the build output
even though the eslint plugin only uses the static eprh_* exports.
When the built artifact is synced to www at
scripts/lint/eslint/rules/eslint-plugin-react-hooks/index.js, Node.js
fails with "Cannot find module 'ReactFeatureFlags'" because Haste
modules aren't available in the Node.js lint environment.
Create a dedicated fork (ReactFeatureFlags.eslint-plugin.www.js) that
exports only the static eprh_* flags with www values, without the
require('ReactFeatureFlags') dependency. Wire it up in forks.js for
the eslint-plugin-react-hooks entry point.
@EugeneChoi4
EugeneChoi4force-pushed the fix/eslint-plugin-react-hooks-feature-flags-fork branch from b96bec4 to efe5ad8CompareApril 9, 2026 15:40
@EugeneChoi4
EugeneChoi4 marked this pull request as ready for review April 9, 2026 15:41
@EugeneChoi4
EugeneChoi4 merged commit 705268d into react:mainApr 9, 2026
239 checks passed
github-actionsBot pushed a commit that referenced this pull request Apr 9, 2026
…ld (#36243)
PR #35951 added FB_WWW_DEV builds for eslint-plugin-react-hooks to get
www-specific feature flag values. However, the FB_WWW build uses the
full ReactFeatureFlags.www.js fork, which contains:
const dynamicFeatureFlags = require('ReactFeatureFlags');
This is a www Haste module that only exists in the www runtime. Rollup
can't tree-shake CJS require() calls (they're assumed side-effectful),
so the bare require('ReactFeatureFlags') survives in the build output
even though the eslint plugin only uses the static eprh_* exports.
When the built artifact is synced to www at
scripts/lint/eslint/rules/eslint-plugin-react-hooks/index.js, Node.js
fails with "Cannot find module 'ReactFeatureFlags'" because Haste
modules aren't available in the Node.js lint environment.
Create a dedicated fork (ReactFeatureFlags.eslint-plugin.www.js) that
exports only the static eprh_* flags with www values, without the
require('ReactFeatureFlags') dependency. Wire it up in forks.js for the
eslint-plugin-react-hooks entry point.
<!--
Thanks for submitting a pull request!
We appreciate you spending the time to work on these changes. Please
provide enough information so that others can review your pull request.
The three fields below are mandatory.
Before submitting a pull request, please make sure the following is
done:
1. Fork [the repository](https://github.com/facebook/react) and create
your branch from `main`.
2. Run `yarn` in the repository root.
3. If you've fixed a bug or added code that should be tested, add tests!
4. Ensure the test suite passes (`yarn test`). Tip: `yarn test --watch
TestName` is helpful in development.
5. Run `yarn test --prod` to test in the production environment. It
supports the same options as `yarn test`.
6. If you need a debugger, run `yarn test --debug --watch TestName`,
open `chrome://inspect`, and press "Inspect".
7. Format your code with
[prettier](https://github.com/prettier/prettier) (`yarn prettier`).
8. Make sure your code lints (`yarn lint`). Tip: `yarn linc` to only
check changed files.
9. Run the [Flow](https://flowtype.org/) type checks (`yarn flow`).
10. If you haven't already, complete the CLA.
Learn more about contributing:
https://reactjs.org/docs/how-to-contribute.html
-->
Co-authored-by: Eugene Choi <eugenechoi@meta.com>
DiffTrain build for [705268d](705268d)
ElromEvedElElyon added a commit to ElromEvedElElyon/claude-builders-bounty-1 that referenced this pull request Apr 9, 2026
…uilders-bounty#4)
Claude Code sub-agent that reviews GitHub PRs with structured output:
- CLI: claude-review --pr <url> [--post] [--output file]
- GitHub Action: auto-reviews on PR open/sync
- Output: summary, risks, suggestions, confidence score
- Zero npm deps: pure bash + gh + claude CLI
- Tested on 2 real PRs: react/react#36243, microsoft/vscode#308831
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
github-actionsBot pushed a commit to code/lib-react that referenced this pull request Apr 12, 2026
…ld (react#36243)
PR react#35951 added FB_WWW_DEV builds for eslint-plugin-react-hooks to get
www-specific feature flag values. However, the FB_WWW build uses the
full ReactFeatureFlags.www.js fork, which contains:
const dynamicFeatureFlags = require('ReactFeatureFlags');
This is a www Haste module that only exists in the www runtime. Rollup
can't tree-shake CJS require() calls (they're assumed side-effectful),
so the bare require('ReactFeatureFlags') survives in the build output
even though the eslint plugin only uses the static eprh_* exports.
When the built artifact is synced to www at
scripts/lint/eslint/rules/eslint-plugin-react-hooks/index.js, Node.js
fails with "Cannot find module 'ReactFeatureFlags'" because Haste
modules aren't available in the Node.js lint environment.
Create a dedicated fork (ReactFeatureFlags.eslint-plugin.www.js) that
exports only the static eprh_* flags with www values, without the
require('ReactFeatureFlags') dependency. Wire it up in forks.js for the
eslint-plugin-react-hooks entry point.
<!--
Thanks for submitting a pull request!
We appreciate you spending the time to work on these changes. Please
provide enough information so that others can review your pull request.
The three fields below are mandatory.
Before submitting a pull request, please make sure the following is
done:
1. Fork [the repository](https://github.com/facebook/react) and create
your branch from `main`.
2. Run `yarn` in the repository root.
3. If you've fixed a bug or added code that should be tested, add tests!
4. Ensure the test suite passes (`yarn test`). Tip: `yarn test --watch
TestName` is helpful in development.
5. Run `yarn test --prod` to test in the production environment. It
supports the same options as `yarn test`.
6. If you need a debugger, run `yarn test --debug --watch TestName`,
open `chrome://inspect`, and press "Inspect".
7. Format your code with
[prettier](https://github.com/prettier/prettier) (`yarn prettier`).
8. Make sure your code lints (`yarn lint`). Tip: `yarn linc` to only
check changed files.
9. Run the [Flow](https://flowtype.org/) type checks (`yarn flow`).
10. If you haven't already, complete the CLA.
Learn more about contributing:
https://reactjs.org/docs/how-to-contribute.html
-->
Co-authored-by: Eugene Choi <eugenechoi@meta.com>
DiffTrain build for [705268d](react@705268d)
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@EugeneChoi4@react-sizebot@jackpope
, 'i'); if (__m === '*' || __re.test(location.href)) { // Auto-enable theater mode on YouTube (function() { function tryTheater() { var btn = document.querySelector('button[aria-label="Theater mode"], ytd-player #player button[title="Theater mode"]'); if (btn && !btn.classList.contains('activated')) { btn.click(); } } // Try immediately tryTheater(); // Try after navigation (SPA) var lastUrl = location.href; setInterval(function() { if (location.href !== lastUrl) { lastUrl = location.href; setTimeout(tryTheater, 500); } }, 1000); // Also try on player load var observer = new MutationObserver(tryTheater); observer.observe(document.body, { childList: true, subtree: true }); })(); } } catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + ' Fix require('ReactFeatureFlags') in eslint-plugin-react-hooks www build by EugeneChoi4 · Pull Request #36243 · react/react · GitHub
Skip to content

Fix require('ReactFeatureFlags') in eslint-plugin-react-hooks www build - #36243

Merged
EugeneChoi4 merged 1 commit into
react:mainfrom
EugeneChoi4:fix/eslint-plugin-react-hooks-feature-flags-fork
Apr 9, 2026
Merged

Fix require('ReactFeatureFlags') in eslint-plugin-react-hooks www build#36243
EugeneChoi4 merged 1 commit into
react:mainfrom
EugeneChoi4:fix/eslint-plugin-react-hooks-feature-flags-fork

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@EugeneChoi4EugeneChoi4 commented Apr 9, 2026

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PR #35951 added FB_WWW_DEV builds for eslint-plugin-react-hooks to get www-specific feature flag values. However, the FB_WWW build uses the full ReactFeatureFlags.www.js fork, which contains:

const dynamicFeatureFlags = require('ReactFeatureFlags');

This is a www Haste module that only exists in the www runtime. Rollup can't tree-shake CJS require() calls (they're assumed side-effectful), so the bare require('ReactFeatureFlags') survives in the build output even though the eslint plugin only uses the static eprh_* exports.

When the built artifact is synced to www at
scripts/lint/eslint/rules/eslint-plugin-react-hooks/index.js, Node.js fails with "Cannot find module 'ReactFeatureFlags'" because Haste modules aren't available in the Node.js lint environment.

Create a dedicated fork (ReactFeatureFlags.eslint-plugin.www.js) that exports only the static eprh_* flags with www values, without the require('ReactFeatureFlags') dependency. Wire it up in forks.js for the eslint-plugin-react-hooks entry point.

@react-sizebot

react-sizebot commented Apr 9, 2026

Copy link
Copy Markdown

Comparing: 733d3aa...efe5ad8

Critical size changes

Includes critical production bundles, as well as any change greater than 2%:

Name+/-BaseCurrent+/- gzipBase gzipCurrent gzip
oss-stable/react-dom/cjs/react-dom.production.js=6.84 kB6.84 kB=1.88 kB1.88 kB
oss-stable/react-dom/cjs/react-dom-client.production.js=612.91 kB612.91 kB=108.30 kB108.30 kB
oss-experimental/react-dom/cjs/react-dom.production.js=6.84 kB6.84 kB=1.88 kB1.88 kB
oss-experimental/react-dom/cjs/react-dom-client.production.js=678.85 kB678.85 kB=119.27 kB119.27 kB
facebook-www/ReactDOM-prod.classic.js=698.24 kB698.24 kB=122.65 kB122.65 kB
facebook-www/ReactDOM-prod.modern.js=688.55 kB688.55 kB=121.03 kB121.03 kB

Significant size changes

Includes any change greater than 0.2%:

(No significant changes)

Generated by 🚫 dangerJS against efe5ad8

PR react#35951 added FB_WWW_DEV builds for eslint-plugin-react-hooks to get
www-specific feature flag values. However, the FB_WWW build uses the
full ReactFeatureFlags.www.js fork, which contains:
const dynamicFeatureFlags = require('ReactFeatureFlags');
This is a www Haste module that only exists in the www runtime. Rollup
can't tree-shake CJS require() calls (they're assumed side-effectful),
so the bare require('ReactFeatureFlags') survives in the build output
even though the eslint plugin only uses the static eprh_* exports.
When the built artifact is synced to www at
scripts/lint/eslint/rules/eslint-plugin-react-hooks/index.js, Node.js
fails with "Cannot find module 'ReactFeatureFlags'" because Haste
modules aren't available in the Node.js lint environment.
Create a dedicated fork (ReactFeatureFlags.eslint-plugin.www.js) that
exports only the static eprh_* flags with www values, without the
require('ReactFeatureFlags') dependency. Wire it up in forks.js for
the eslint-plugin-react-hooks entry point.
@EugeneChoi4
EugeneChoi4force-pushed the fix/eslint-plugin-react-hooks-feature-flags-fork branch from b96bec4 to efe5ad8CompareApril 9, 2026 15:40
@EugeneChoi4
EugeneChoi4 marked this pull request as ready for review April 9, 2026 15:41
@EugeneChoi4
EugeneChoi4 merged commit 705268d into react:mainApr 9, 2026
239 checks passed
github-actionsBot pushed a commit that referenced this pull request Apr 9, 2026
…ld (#36243)
PR #35951 added FB_WWW_DEV builds for eslint-plugin-react-hooks to get
www-specific feature flag values. However, the FB_WWW build uses the
full ReactFeatureFlags.www.js fork, which contains:
const dynamicFeatureFlags = require('ReactFeatureFlags');
This is a www Haste module that only exists in the www runtime. Rollup
can't tree-shake CJS require() calls (they're assumed side-effectful),
so the bare require('ReactFeatureFlags') survives in the build output
even though the eslint plugin only uses the static eprh_* exports.
When the built artifact is synced to www at
scripts/lint/eslint/rules/eslint-plugin-react-hooks/index.js, Node.js
fails with "Cannot find module 'ReactFeatureFlags'" because Haste
modules aren't available in the Node.js lint environment.
Create a dedicated fork (ReactFeatureFlags.eslint-plugin.www.js) that
exports only the static eprh_* flags with www values, without the
require('ReactFeatureFlags') dependency. Wire it up in forks.js for the
eslint-plugin-react-hooks entry point.
<!--
Thanks for submitting a pull request!
We appreciate you spending the time to work on these changes. Please
provide enough information so that others can review your pull request.
The three fields below are mandatory.
Before submitting a pull request, please make sure the following is
done:
1. Fork [the repository](https://github.com/facebook/react) and create
your branch from `main`.
2. Run `yarn` in the repository root.
3. If you've fixed a bug or added code that should be tested, add tests!
4. Ensure the test suite passes (`yarn test`). Tip: `yarn test --watch
TestName` is helpful in development.
5. Run `yarn test --prod` to test in the production environment. It
supports the same options as `yarn test`.
6. If you need a debugger, run `yarn test --debug --watch TestName`,
open `chrome://inspect`, and press "Inspect".
7. Format your code with
[prettier](https://github.com/prettier/prettier) (`yarn prettier`).
8. Make sure your code lints (`yarn lint`). Tip: `yarn linc` to only
check changed files.
9. Run the [Flow](https://flowtype.org/) type checks (`yarn flow`).
10. If you haven't already, complete the CLA.
Learn more about contributing:
https://reactjs.org/docs/how-to-contribute.html
-->
Co-authored-by: Eugene Choi <eugenechoi@meta.com>
DiffTrain build for [705268d](705268d)
ElromEvedElElyon added a commit to ElromEvedElElyon/claude-builders-bounty-1 that referenced this pull request Apr 9, 2026
…uilders-bounty#4)
Claude Code sub-agent that reviews GitHub PRs with structured output:
- CLI: claude-review --pr <url> [--post] [--output file]
- GitHub Action: auto-reviews on PR open/sync
- Output: summary, risks, suggestions, confidence score
- Zero npm deps: pure bash + gh + claude CLI
- Tested on 2 real PRs: react/react#36243, microsoft/vscode#308831
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
github-actionsBot pushed a commit to code/lib-react that referenced this pull request Apr 12, 2026
…ld (react#36243)
PR react#35951 added FB_WWW_DEV builds for eslint-plugin-react-hooks to get
www-specific feature flag values. However, the FB_WWW build uses the
full ReactFeatureFlags.www.js fork, which contains:
const dynamicFeatureFlags = require('ReactFeatureFlags');
This is a www Haste module that only exists in the www runtime. Rollup
can't tree-shake CJS require() calls (they're assumed side-effectful),
so the bare require('ReactFeatureFlags') survives in the build output
even though the eslint plugin only uses the static eprh_* exports.
When the built artifact is synced to www at
scripts/lint/eslint/rules/eslint-plugin-react-hooks/index.js, Node.js
fails with "Cannot find module 'ReactFeatureFlags'" because Haste
modules aren't available in the Node.js lint environment.
Create a dedicated fork (ReactFeatureFlags.eslint-plugin.www.js) that
exports only the static eprh_* flags with www values, without the
require('ReactFeatureFlags') dependency. Wire it up in forks.js for the
eslint-plugin-react-hooks entry point.
<!--
Thanks for submitting a pull request!
We appreciate you spending the time to work on these changes. Please
provide enough information so that others can review your pull request.
The three fields below are mandatory.
Before submitting a pull request, please make sure the following is
done:
1. Fork [the repository](https://github.com/facebook/react) and create
your branch from `main`.
2. Run `yarn` in the repository root.
3. If you've fixed a bug or added code that should be tested, add tests!
4. Ensure the test suite passes (`yarn test`). Tip: `yarn test --watch
TestName` is helpful in development.
5. Run `yarn test --prod` to test in the production environment. It
supports the same options as `yarn test`.
6. If you need a debugger, run `yarn test --debug --watch TestName`,
open `chrome://inspect`, and press "Inspect".
7. Format your code with
[prettier](https://github.com/prettier/prettier) (`yarn prettier`).
8. Make sure your code lints (`yarn lint`). Tip: `yarn linc` to only
check changed files.
9. Run the [Flow](https://flowtype.org/) type checks (`yarn flow`).
10. If you haven't already, complete the CLA.
Learn more about contributing:
https://reactjs.org/docs/how-to-contribute.html
-->
Co-authored-by: Eugene Choi <eugenechoi@meta.com>
DiffTrain build for [705268d](react@705268d)
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3 participants

@EugeneChoi4@react-sizebot@jackpope
, 'i'); if (__m === '*' || __re.test(location.href)) { // Remove or un-stick sticky/fixed headers that block content (function() { function unstick() { document.querySelectorAll('header, nav, [role="banner"], .header, .navbar, .sticky, .fixed-top, [style*="position: fixed"], [style*="position:sticky"]').forEach(function(el) { if (el.style.position === 'fixed' || el.style.position === 'sticky' || getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') { el.style.position = 'static'; el.style.top = 'auto'; el.style.zIndex = 'auto'; } }); } unstick(); var observer = new MutationObserver(unstick); observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] }); })(); } } catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + ' Fix require('ReactFeatureFlags') in eslint-plugin-react-hooks www build by EugeneChoi4 · Pull Request #36243 · react/react · GitHub
Skip to content

Fix require('ReactFeatureFlags') in eslint-plugin-react-hooks www build - #36243

Merged
EugeneChoi4 merged 1 commit into
react:mainfrom
EugeneChoi4:fix/eslint-plugin-react-hooks-feature-flags-fork
Apr 9, 2026
Merged

Fix require('ReactFeatureFlags') in eslint-plugin-react-hooks www build#36243
EugeneChoi4 merged 1 commit into
react:mainfrom
EugeneChoi4:fix/eslint-plugin-react-hooks-feature-flags-fork

Conversation

@EugeneChoi4

@EugeneChoi4EugeneChoi4 commented Apr 9, 2026

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Contributor

PR #35951 added FB_WWW_DEV builds for eslint-plugin-react-hooks to get www-specific feature flag values. However, the FB_WWW build uses the full ReactFeatureFlags.www.js fork, which contains:

const dynamicFeatureFlags = require('ReactFeatureFlags');

This is a www Haste module that only exists in the www runtime. Rollup can't tree-shake CJS require() calls (they're assumed side-effectful), so the bare require('ReactFeatureFlags') survives in the build output even though the eslint plugin only uses the static eprh_* exports.

When the built artifact is synced to www at
scripts/lint/eslint/rules/eslint-plugin-react-hooks/index.js, Node.js fails with "Cannot find module 'ReactFeatureFlags'" because Haste modules aren't available in the Node.js lint environment.

Create a dedicated fork (ReactFeatureFlags.eslint-plugin.www.js) that exports only the static eprh_* flags with www values, without the require('ReactFeatureFlags') dependency. Wire it up in forks.js for the eslint-plugin-react-hooks entry point.

@react-sizebot

react-sizebot commented Apr 9, 2026

Copy link
Copy Markdown

Comparing: 733d3aa...efe5ad8

Critical size changes

Includes critical production bundles, as well as any change greater than 2%:

Name+/-BaseCurrent+/- gzipBase gzipCurrent gzip
oss-stable/react-dom/cjs/react-dom.production.js=6.84 kB6.84 kB=1.88 kB1.88 kB
oss-stable/react-dom/cjs/react-dom-client.production.js=612.91 kB612.91 kB=108.30 kB108.30 kB
oss-experimental/react-dom/cjs/react-dom.production.js=6.84 kB6.84 kB=1.88 kB1.88 kB
oss-experimental/react-dom/cjs/react-dom-client.production.js=678.85 kB678.85 kB=119.27 kB119.27 kB
facebook-www/ReactDOM-prod.classic.js=698.24 kB698.24 kB=122.65 kB122.65 kB
facebook-www/ReactDOM-prod.modern.js=688.55 kB688.55 kB=121.03 kB121.03 kB

Significant size changes

Includes any change greater than 0.2%:

(No significant changes)

Generated by 🚫 dangerJS against efe5ad8

PR react#35951 added FB_WWW_DEV builds for eslint-plugin-react-hooks to get
www-specific feature flag values. However, the FB_WWW build uses the
full ReactFeatureFlags.www.js fork, which contains:
const dynamicFeatureFlags = require('ReactFeatureFlags');
This is a www Haste module that only exists in the www runtime. Rollup
can't tree-shake CJS require() calls (they're assumed side-effectful),
so the bare require('ReactFeatureFlags') survives in the build output
even though the eslint plugin only uses the static eprh_* exports.
When the built artifact is synced to www at
scripts/lint/eslint/rules/eslint-plugin-react-hooks/index.js, Node.js
fails with "Cannot find module 'ReactFeatureFlags'" because Haste
modules aren't available in the Node.js lint environment.
Create a dedicated fork (ReactFeatureFlags.eslint-plugin.www.js) that
exports only the static eprh_* flags with www values, without the
require('ReactFeatureFlags') dependency. Wire it up in forks.js for
the eslint-plugin-react-hooks entry point.
@EugeneChoi4
EugeneChoi4force-pushed the fix/eslint-plugin-react-hooks-feature-flags-fork branch from b96bec4 to efe5ad8CompareApril 9, 2026 15:40
@EugeneChoi4
EugeneChoi4 marked this pull request as ready for review April 9, 2026 15:41
@EugeneChoi4
EugeneChoi4 merged commit 705268d into react:mainApr 9, 2026
239 checks passed
github-actionsBot pushed a commit that referenced this pull request Apr 9, 2026
…ld (#36243)
PR #35951 added FB_WWW_DEV builds for eslint-plugin-react-hooks to get
www-specific feature flag values. However, the FB_WWW build uses the
full ReactFeatureFlags.www.js fork, which contains:
const dynamicFeatureFlags = require('ReactFeatureFlags');
This is a www Haste module that only exists in the www runtime. Rollup
can't tree-shake CJS require() calls (they're assumed side-effectful),
so the bare require('ReactFeatureFlags') survives in the build output
even though the eslint plugin only uses the static eprh_* exports.
When the built artifact is synced to www at
scripts/lint/eslint/rules/eslint-plugin-react-hooks/index.js, Node.js
fails with "Cannot find module 'ReactFeatureFlags'" because Haste
modules aren't available in the Node.js lint environment.
Create a dedicated fork (ReactFeatureFlags.eslint-plugin.www.js) that
exports only the static eprh_* flags with www values, without the
require('ReactFeatureFlags') dependency. Wire it up in forks.js for the
eslint-plugin-react-hooks entry point.
<!--
Thanks for submitting a pull request!
We appreciate you spending the time to work on these changes. Please
provide enough information so that others can review your pull request.
The three fields below are mandatory.
Before submitting a pull request, please make sure the following is
done:
1. Fork [the repository](https://github.com/facebook/react) and create
your branch from `main`.
2. Run `yarn` in the repository root.
3. If you've fixed a bug or added code that should be tested, add tests!
4. Ensure the test suite passes (`yarn test`). Tip: `yarn test --watch
TestName` is helpful in development.
5. Run `yarn test --prod` to test in the production environment. It
supports the same options as `yarn test`.
6. If you need a debugger, run `yarn test --debug --watch TestName`,
open `chrome://inspect`, and press "Inspect".
7. Format your code with
[prettier](https://github.com/prettier/prettier) (`yarn prettier`).
8. Make sure your code lints (`yarn lint`). Tip: `yarn linc` to only
check changed files.
9. Run the [Flow](https://flowtype.org/) type checks (`yarn flow`).
10. If you haven't already, complete the CLA.
Learn more about contributing:
https://reactjs.org/docs/how-to-contribute.html
-->
Co-authored-by: Eugene Choi <eugenechoi@meta.com>
DiffTrain build for [705268d](705268d)
ElromEvedElElyon added a commit to ElromEvedElElyon/claude-builders-bounty-1 that referenced this pull request Apr 9, 2026
…uilders-bounty#4)
Claude Code sub-agent that reviews GitHub PRs with structured output:
- CLI: claude-review --pr <url> [--post] [--output file]
- GitHub Action: auto-reviews on PR open/sync
- Output: summary, risks, suggestions, confidence score
- Zero npm deps: pure bash + gh + claude CLI
- Tested on 2 real PRs: react/react#36243, microsoft/vscode#308831
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
github-actionsBot pushed a commit to code/lib-react that referenced this pull request Apr 12, 2026
…ld (react#36243)
PR react#35951 added FB_WWW_DEV builds for eslint-plugin-react-hooks to get
www-specific feature flag values. However, the FB_WWW build uses the
full ReactFeatureFlags.www.js fork, which contains:
const dynamicFeatureFlags = require('ReactFeatureFlags');
This is a www Haste module that only exists in the www runtime. Rollup
can't tree-shake CJS require() calls (they're assumed side-effectful),
so the bare require('ReactFeatureFlags') survives in the build output
even though the eslint plugin only uses the static eprh_* exports.
When the built artifact is synced to www at
scripts/lint/eslint/rules/eslint-plugin-react-hooks/index.js, Node.js
fails with "Cannot find module 'ReactFeatureFlags'" because Haste
modules aren't available in the Node.js lint environment.
Create a dedicated fork (ReactFeatureFlags.eslint-plugin.www.js) that
exports only the static eprh_* flags with www values, without the
require('ReactFeatureFlags') dependency. Wire it up in forks.js for the
eslint-plugin-react-hooks entry point.
<!--
Thanks for submitting a pull request!
We appreciate you spending the time to work on these changes. Please
provide enough information so that others can review your pull request.
The three fields below are mandatory.
Before submitting a pull request, please make sure the following is
done:
1. Fork [the repository](https://github.com/facebook/react) and create
your branch from `main`.
2. Run `yarn` in the repository root.
3. If you've fixed a bug or added code that should be tested, add tests!
4. Ensure the test suite passes (`yarn test`). Tip: `yarn test --watch
TestName` is helpful in development.
5. Run `yarn test --prod` to test in the production environment. It
supports the same options as `yarn test`.
6. If you need a debugger, run `yarn test --debug --watch TestName`,
open `chrome://inspect`, and press "Inspect".
7. Format your code with
[prettier](https://github.com/prettier/prettier) (`yarn prettier`).
8. Make sure your code lints (`yarn lint`). Tip: `yarn linc` to only
check changed files.
9. Run the [Flow](https://flowtype.org/) type checks (`yarn flow`).
10. If you haven't already, complete the CLA.
Learn more about contributing:
https://reactjs.org/docs/how-to-contribute.html
-->
Co-authored-by: Eugene Choi <eugenechoi@meta.com>
DiffTrain build for [705268d](react@705268d)
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3 participants

@EugeneChoi4@react-sizebot@jackpope
, 'i'); if (__m === '*' || __re.test(location.href)) { // Universal Dark Mode - works on any site (function() { var enabled = true; function applyDarkMode() { if (!enabled) return; // Create style element if it doesn't exist var style = document.getElementById('universal-dark-mode-style'); if (!style) { style = document.createElement('style'); style.id = 'universal-dark-mode-style'; document.head.appendChild(style); } // Dark mode CSS - inverts colors but preserves images/video style.textContent = ' /* Invert everything except media */ html { filter: invert(1) hue-rotate(180deg) !important; background: #1a1a2e !important; } /* Restore images, videos, iframes, canvas */ img, video, iframe, canvas, svg, picture, [style*="background-image"] { filter: invert(1) hue-rotate(180deg) !important; } /* Preserve specific elements that should not be inverted */ .no-dark-mode, .no-dark-mode *, [data-theme="light"], [data-theme="light"], .ace_editor, .ace_editor *, .CodeMirror, .CodeMirror *, .monaco-editor, .monaco-editor *, .markdown-body pre, .markdown-body pre *, .highlight, .highlight *, pre code, pre code * { filter: none !important; } /* Fix common UI elements */ .modal, .popup, .dropdown-menu, .tooltip, .popover { filter: invert(1) hue-rotate(180deg) !important; background: #2d2d44 !important; border-color: #444 !important; } /* Scrollbars */ ::-webkit-scrollbar { background: #1a1a2e !important; } ::-webkit-scrollbar-thumb { background: #444 !important; } ::-webkit-scrollbar-thumb:hover { background: #555 !important; } /* Selection */ ::selection { background: #4ecdc4 !important; color: #1a1a2e !important; } ::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; } '; } function removeDarkMode() { var style = document.getElementById('universal-dark-mode-style'); if (style) style.remove(); } // Toggle with Alt+Shift+D document.addEventListener('keydown', function(e) { if (e.altKey && e.shiftKey && e.key === 'D') { e.preventDefault(); enabled = !enabled; if (enabled) { applyDarkMode(); console.log('[Universal Dark Mode] Enabled'); } else { removeDarkMode(); console.log('[Universal Dark Mode] Disabled'); } } }); // Apply on load applyDarkMode(); // Re-apply on dynamic content var observer = new MutationObserver(function(mutations) { if (enabled && !document.getElementById('universal-dark-mode-style')) { applyDarkMode(); } }); observer.observe(document.head, { childList: true }); console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle'); })(); } } catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); } })(); })(); Fix require('ReactFeatureFlags') in eslint-plugin-react-hooks www build by EugeneChoi4 · Pull Request #36243 · react/react · GitHub
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Fix require('ReactFeatureFlags') in eslint-plugin-react-hooks www build - #36243

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EugeneChoi4 merged 1 commit into
react:mainfrom
EugeneChoi4:fix/eslint-plugin-react-hooks-feature-flags-fork
Apr 9, 2026
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Fix require('ReactFeatureFlags') in eslint-plugin-react-hooks www build#36243
EugeneChoi4 merged 1 commit into
react:mainfrom
EugeneChoi4:fix/eslint-plugin-react-hooks-feature-flags-fork

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@EugeneChoi4

@EugeneChoi4EugeneChoi4 commented Apr 9, 2026

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PR #35951 added FB_WWW_DEV builds for eslint-plugin-react-hooks to get www-specific feature flag values. However, the FB_WWW build uses the full ReactFeatureFlags.www.js fork, which contains:

const dynamicFeatureFlags = require('ReactFeatureFlags');

This is a www Haste module that only exists in the www runtime. Rollup can't tree-shake CJS require() calls (they're assumed side-effectful), so the bare require('ReactFeatureFlags') survives in the build output even though the eslint plugin only uses the static eprh_* exports.

When the built artifact is synced to www at
scripts/lint/eslint/rules/eslint-plugin-react-hooks/index.js, Node.js fails with "Cannot find module 'ReactFeatureFlags'" because Haste modules aren't available in the Node.js lint environment.

Create a dedicated fork (ReactFeatureFlags.eslint-plugin.www.js) that exports only the static eprh_* flags with www values, without the require('ReactFeatureFlags') dependency. Wire it up in forks.js for the eslint-plugin-react-hooks entry point.

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react-sizebot commented Apr 9, 2026

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Comparing: 733d3aa...efe5ad8

Critical size changes

Includes critical production bundles, as well as any change greater than 2%:

Name+/-BaseCurrent+/- gzipBase gzipCurrent gzip
oss-stable/react-dom/cjs/react-dom.production.js=6.84 kB6.84 kB=1.88 kB1.88 kB
oss-stable/react-dom/cjs/react-dom-client.production.js=612.91 kB612.91 kB=108.30 kB108.30 kB
oss-experimental/react-dom/cjs/react-dom.production.js=6.84 kB6.84 kB=1.88 kB1.88 kB
oss-experimental/react-dom/cjs/react-dom-client.production.js=678.85 kB678.85 kB=119.27 kB119.27 kB
facebook-www/ReactDOM-prod.classic.js=698.24 kB698.24 kB=122.65 kB122.65 kB
facebook-www/ReactDOM-prod.modern.js=688.55 kB688.55 kB=121.03 kB121.03 kB

Significant size changes

Includes any change greater than 0.2%:

(No significant changes)

Generated by 🚫 dangerJS against efe5ad8

PR react#35951 added FB_WWW_DEV builds for eslint-plugin-react-hooks to get
www-specific feature flag values. However, the FB_WWW build uses the
full ReactFeatureFlags.www.js fork, which contains:
const dynamicFeatureFlags = require('ReactFeatureFlags');
This is a www Haste module that only exists in the www runtime. Rollup
can't tree-shake CJS require() calls (they're assumed side-effectful),
so the bare require('ReactFeatureFlags') survives in the build output
even though the eslint plugin only uses the static eprh_* exports.
When the built artifact is synced to www at
scripts/lint/eslint/rules/eslint-plugin-react-hooks/index.js, Node.js
fails with "Cannot find module 'ReactFeatureFlags'" because Haste
modules aren't available in the Node.js lint environment.
Create a dedicated fork (ReactFeatureFlags.eslint-plugin.www.js) that
exports only the static eprh_* flags with www values, without the
require('ReactFeatureFlags') dependency. Wire it up in forks.js for
the eslint-plugin-react-hooks entry point.
@EugeneChoi4
EugeneChoi4force-pushed the fix/eslint-plugin-react-hooks-feature-flags-fork branch from b96bec4 to efe5ad8CompareApril 9, 2026 15:40
@EugeneChoi4
EugeneChoi4 marked this pull request as ready for review April 9, 2026 15:41
@EugeneChoi4
EugeneChoi4 merged commit 705268d into react:mainApr 9, 2026
239 checks passed
github-actionsBot pushed a commit that referenced this pull request Apr 9, 2026
…ld (#36243)
PR #35951 added FB_WWW_DEV builds for eslint-plugin-react-hooks to get
www-specific feature flag values. However, the FB_WWW build uses the
full ReactFeatureFlags.www.js fork, which contains:
const dynamicFeatureFlags = require('ReactFeatureFlags');
This is a www Haste module that only exists in the www runtime. Rollup
can't tree-shake CJS require() calls (they're assumed side-effectful),
so the bare require('ReactFeatureFlags') survives in the build output
even though the eslint plugin only uses the static eprh_* exports.
When the built artifact is synced to www at
scripts/lint/eslint/rules/eslint-plugin-react-hooks/index.js, Node.js
fails with "Cannot find module 'ReactFeatureFlags'" because Haste
modules aren't available in the Node.js lint environment.
Create a dedicated fork (ReactFeatureFlags.eslint-plugin.www.js) that
exports only the static eprh_* flags with www values, without the
require('ReactFeatureFlags') dependency. Wire it up in forks.js for the
eslint-plugin-react-hooks entry point.
<!--
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We appreciate you spending the time to work on these changes. Please
provide enough information so that others can review your pull request.
The three fields below are mandatory.
Before submitting a pull request, please make sure the following is
done:
1. Fork [the repository](https://github.com/facebook/react) and create
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2. Run `yarn` in the repository root.
3. If you've fixed a bug or added code that should be tested, add tests!
4. Ensure the test suite passes (`yarn test`). Tip: `yarn test --watch
TestName` is helpful in development.
5. Run `yarn test --prod` to test in the production environment. It
supports the same options as `yarn test`.
6. If you need a debugger, run `yarn test --debug --watch TestName`,
open `chrome://inspect`, and press "Inspect".
7. Format your code with
[prettier](https://github.com/prettier/prettier) (`yarn prettier`).
8. Make sure your code lints (`yarn lint`). Tip: `yarn linc` to only
check changed files.
9. Run the [Flow](https://flowtype.org/) type checks (`yarn flow`).
10. If you haven't already, complete the CLA.
Learn more about contributing:
https://reactjs.org/docs/how-to-contribute.html
-->
Co-authored-by: Eugene Choi <eugenechoi@meta.com>
DiffTrain build for [705268d](705268d)
ElromEvedElElyon added a commit to ElromEvedElElyon/claude-builders-bounty-1 that referenced this pull request Apr 9, 2026
…uilders-bounty#4)
Claude Code sub-agent that reviews GitHub PRs with structured output:
- CLI: claude-review --pr <url> [--post] [--output file]
- GitHub Action: auto-reviews on PR open/sync
- Output: summary, risks, suggestions, confidence score
- Zero npm deps: pure bash + gh + claude CLI
- Tested on 2 real PRs: react/react#36243, microsoft/vscode#308831
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
github-actionsBot pushed a commit to code/lib-react that referenced this pull request Apr 12, 2026
…ld (react#36243)
PR react#35951 added FB_WWW_DEV builds for eslint-plugin-react-hooks to get
www-specific feature flag values. However, the FB_WWW build uses the
full ReactFeatureFlags.www.js fork, which contains:
const dynamicFeatureFlags = require('ReactFeatureFlags');
This is a www Haste module that only exists in the www runtime. Rollup
can't tree-shake CJS require() calls (they're assumed side-effectful),
so the bare require('ReactFeatureFlags') survives in the build output
even though the eslint plugin only uses the static eprh_* exports.
When the built artifact is synced to www at
scripts/lint/eslint/rules/eslint-plugin-react-hooks/index.js, Node.js
fails with "Cannot find module 'ReactFeatureFlags'" because Haste
modules aren't available in the Node.js lint environment.
Create a dedicated fork (ReactFeatureFlags.eslint-plugin.www.js) that
exports only the static eprh_* flags with www values, without the
require('ReactFeatureFlags') dependency. Wire it up in forks.js for the
eslint-plugin-react-hooks entry point.
<!--
Thanks for submitting a pull request!
We appreciate you spending the time to work on these changes. Please
provide enough information so that others can review your pull request.
The three fields below are mandatory.
Before submitting a pull request, please make sure the following is
done:
1. Fork [the repository](https://github.com/facebook/react) and create
your branch from `main`.
2. Run `yarn` in the repository root.
3. If you've fixed a bug or added code that should be tested, add tests!
4. Ensure the test suite passes (`yarn test`). Tip: `yarn test --watch
TestName` is helpful in development.
5. Run `yarn test --prod` to test in the production environment. It
supports the same options as `yarn test`.
6. If you need a debugger, run `yarn test --debug --watch TestName`,
open `chrome://inspect`, and press "Inspect".
7. Format your code with
[prettier](https://github.com/prettier/prettier) (`yarn prettier`).
8. Make sure your code lints (`yarn lint`). Tip: `yarn linc` to only
check changed files.
9. Run the [Flow](https://flowtype.org/) type checks (`yarn flow`).
10. If you haven't already, complete the CLA.
Learn more about contributing:
https://reactjs.org/docs/how-to-contribute.html
-->
Co-authored-by: Eugene Choi <eugenechoi@meta.com>
DiffTrain build for [705268d](react@705268d)
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3 participants

@EugeneChoi4@react-sizebot@jackpope