Modernize: Replace fs-extra with native APIs

[y-hsgw]

Closes #20228

What I did

This PR replaces fs-extra with the native APIs.

Checklist for Contributors

Testing

The changes in this PR are covered in the following automated tests:

• stories
• unit tests
• integration tests
• end-to-end tests

Manual testing

Run yarn test and yarn build-package under the scripts/ directory.

Documentation

• Add or update documentation reflecting your changes
• If you are deprecating/removing a feature, make sure to update
  MIGRATION.MD

Checklist for Maintainers

• When this PR is ready for testing, make sure to add ci:normal, ci:merged or ci:daily GH label to it to run a specific set of sandboxes. The particular set of sandboxes can be found in code/lib/cli-storybook/src/sandbox-templates.ts

• Make sure this PR contains one of the labels below:

  Available labels

  • bug: Internal changes that fixes incorrect behavior.
  • maintenance: User-facing maintenance tasks.
  • dependencies: Upgrading (sometimes downgrading) dependencies.
  • build: Internal-facing build tooling & test updates. Will not show up in release changelog.
  • cleanup: Minor cleanup style change. Will not show up in release changelog.
  • documentation: Documentation only changes. Will not show up in release changelog.
  • feature request: Introducing a new feature.
  • BREAKING CHANGE: Changes that break compatibility in some way with current major version.
  • other: Changes that don't fit in the above categories.

🦋 Canary release

This PR does not have a canary release associated. You can request a canary release of this pull request by mentioning the @storybookjs/core team here.

core team members can create a canary release here or locally with gh workflow run --repo storybookjs/storybook canary-release-pr.yml --field pr=<PR_NUMBER>

Greptile Summary

This PR systematically replaces the fs-extra dependency with native Node.js filesystem APIs across the entire scripts directory. The migration touches 35+ files and removes fs-extra from the package.json dependencies. Key changes include:

• Import replacements: All fs-extra imports are replaced with node:fs/promises imports (readFile, writeFile, rm, cp, access, etc.)
• Custom utility functions: Several files implement custom helper functions to replicate fs-extra functionality:
  • pathExists() using access() with try-catch error handling
  • readJson() using readFile() + JSON.parse()
  • emptyDir() using mkdir() + readdir() + rm()
  • outputFile() using mkdir(dirname()) + writeFile()
• JSON operations: Replaces readJson/writeJson with manual readFile/writeFile + JSON.parse/JSON.stringify
• File operations: Replaces copy with cp, remove with rm, move with rename, ensureDir with mkdir
• Test updates: Updates test mocks and expectations to work with native APIs instead of fs-extra
• ESLint config: Removes fs-extra from the banned dependencies list

This change aligns with modern Node.js best practices of leveraging native APIs when equivalent functionality exists, reducing the dependency footprint from 1 external package to 0. The migration affects build scripts, release automation, sandbox generation, and various utility functions throughout the development toolchain. All changes maintain functional equivalence while using only built-in Node.js capabilities available since Node.js 14+.

Confidence score: 2/5

• This PR has a critical runtime bug that will cause immediate failures in production
• Score reflects a missing function reference in scripts/reset.js that will throw a ReferenceError
• Pay close attention to scripts/reset.js which calls remove(uri) on line 45 but only imports rm() from native APIs

[greptile-apps]

_{36 files reviewed, 10 comments}

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[nx-cloud]

View your CI Pipeline Execution ↗ for commit 9bb3db0

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☁️ Nx Cloud last updated this comment at 2025-09-04 10:03:01 UTC

[Copilot]

Pull Request Overview

This PR modernizes the scripts directory by replacing the fs-extra dependency with native Node.js filesystem APIs. This reduces the dependency footprint and aligns with modern Node.js best practices by leveraging built-in functionality available since Node.js 14+.

Key changes include:

• Replacing all fs-extra imports with node:fs/promises imports across 35+ files
• Implementing custom utility functions to replicate specific fs-extra functionality where needed
• Removing fs-extra from package.json dependencies and ESLint banned dependencies

Reviewed Changes

Copilot reviewed 35 out of 36 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
scripts/utils/yarn.ts	Replace readJSON/writeJSON with manual JSON parsing/stringifying
scripts/utils/tools.ts	Replace pathExists and readJson with native access and readFile
scripts/utils/paths.ts	Replace pathExists with custom implementation using access
scripts/utils/package-json.ts	Replace readJSON/writeJSON with native file operations
scripts/utils/filterExistsInCodeDir.ts	Replace pathExists with custom implementation
scripts/tasks/sandbox.ts	Replace pathExists and remove with access and rm
scripts/tasks/sandbox-parts.ts	Replace multiple fs-extra functions with native equivalents and custom utilities
scripts/tasks/publish.ts	Replace pathExists with custom implementation
scripts/tasks/install.ts	Replace pathExists and remove with access and rm
scripts/tasks/generate.ts	Replace pathExists and remove with access and rm
scripts/tasks/compile.ts	Replace readFile import with native equivalent
scripts/tasks/build.ts	Replace pathExists with custom implementation
scripts/task.ts	Replace outputFile and pathExists with custom implementations
scripts/sandbox/utils/yarn.ts	Replace move, remove with rename, rm
scripts/sandbox/utils/template.ts	Replace readFile import with native equivalent
scripts/sandbox/publish.ts	Replace copy, emptyDir, remove with native equivalents and custom utilities
scripts/sandbox/generate.ts	Replace multiple fs-extra functions with native equivalents and custom utilities
scripts/run-registry.ts	Replace pathExists, readJSON, remove with native equivalents
scripts/reset.js	Replace remove with rm
scripts/release/ files	Replace readFile, readJson, writeJson with native equivalents across multiple release scripts
scripts/package.json	Remove fs-extra and @types/fs-extra dependencies
scripts/get-template.ts	Replace pathExists and readFile with native equivalents
scripts/get-report-message.ts	Replace readJson with native file operations
scripts/combine-compodoc.ts	Replace fs-extra imports with native equivalents
scripts/check-package.ts	Replace readJSON with native file operations
scripts/build-package.ts	Replace readJSON with native file operations
scripts/bench/utils.ts	Replace multiple fs-extra functions with native equivalents

Comments suppressed due to low confidence (1)

scripts/reset.js:1

• The function remove is not defined. The import statement imports rm from node:fs/promises, but the code still calls remove(uri). This should be changed to rm(uri, { force: true, recursive: true }).

import { spawn } from 'node:child_process';

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