Addon-Vitest: Fix postinstall a11y installation

[valentinpalkovic]

Closes #33844

What I did

Fixed an issue where packages were executed via yarn exec, although the package contained a version. for this case, either npx (yarn 1) or yarn dlx (yarn berry) should be used.

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

Caution

This section is mandatory for all contributions. If you believe no manual test is necessary, please state so explicitly. Thanks!

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.

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Summary by CodeRabbit

• New Features
  • Added optional parameter to support alternative remote package execution methods in Yarn package managers, enabling users to choose between standard and direct execution modes.

[github-actions]

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☁️ Nx Cloud last updated this comment at 2026-02-23 14:16:36 UTC

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☁️ Nx Cloud last updated this comment at 2026-02-20 13:07:14 UTC

[coderabbitai]

📝 Walkthrough

Walkthrough

Both Yarn proxy implementations now support an optional useRemotePkg flag in their runPackageCommand method. When enabled, commands execute via npx (Yarn1) or dlx (Yarn2) directly instead of through yarn's exec subcommand, bypassing the package manager wrapper.

Changes

Cohort / File(s)	Summary
Package Manager Proxy Updates code/core/src/common/js-package-manager/Yarn1Proxy.ts, code/core/src/common/js-package-manager/Yarn2Proxy.ts	Added optional useRemotePkg?: boolean parameter to runPackageCommand method. When true, executes command via npx/dlx directly; defaults to false preserving existing yarn exec behavior.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~10 minutes

Possibly related PRs

• storybookjs/storybook#33718: Directly related PR that modifies the js-package-manager API to add the same useRemotePkg flag for selecting dlx/npx execution behavior.

✨ Finishing Touches

• 📝 Generate docstrings (stacked PR)
• 📝 Generate docstrings (commit on current branch)

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[coderabbitai]

Caution

Some comments are outside the diff and can’t be posted inline due to platform limitations.

⚠️ Outside diff range comments (1)

code/core/src/common/js-package-manager/Yarn1Proxy.ts (1)

58-77: ⚠️ Potential issue | 🟠 Major

Forward ExecuteCommandOptions in the npx path.

Line 67-71 drops cwd, env, stdio, signal, and ignoreError when useRemotePkg is true. That changes runtime behavior vs. the yarn exec path and can break callers that rely on those options.

🛠️ Proposed fix

     if (useRemotePkg) {
       return executeCommand({
         command: 'npx',
         args,
+        ...options,
       });
     }

🤖 Prompt for AI Agents

Verify each finding against the current code and only fix it if needed.

In `@code/core/src/common/js-package-manager/Yarn1Proxy.ts` around lines 58 - 77,
The npx branch in Yarn1Proxy.runPackageCommand is not forwarding
ExecuteCommandOptions (cwd, env, stdio, signal, ignoreError) causing different
runtime behavior; modify the useRemotePkg path so it calls executeCommand with
command: 'npx', args: args, and spreads the remaining options (i.e., include
...options) so the same ExecuteCommandOptions passed into runPackageCommand
reach executeCommand; keep destructuring of args/useRemotePkg as-is and ensure
no duplicate/conflicting fields are created when merging options.

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Outside diff comments:
In `@code/core/src/common/js-package-manager/Yarn1Proxy.ts`:
- Around line 58-77: The npx branch in Yarn1Proxy.runPackageCommand is not
forwarding ExecuteCommandOptions (cwd, env, stdio, signal, ignoreError) causing
different runtime behavior; modify the useRemotePkg path so it calls
executeCommand with command: 'npx', args: args, and spreads the remaining
options (i.e., include ...options) so the same ExecuteCommandOptions passed into
runPackageCommand reach executeCommand; keep destructuring of args/useRemotePkg
as-is and ensure no duplicate/conflicting fields are created when merging
options.

[storybook-app-bot]

Package Benchmarks

^{Commit: 086dbce, ran on 23 February 2026 at 14:16:52 UTC}

The following packages have significant changes to their size or dependencies:

@storybook/nextjs

	Before	After	Difference
Dependency count	535	535	0
Self size	648 KB	648 KB	🎉 -240 B 🎉
Dependency size	59.87 MB	59.91 MB	🚨 +37 KB 🚨
Bundle Size Analyzer	Link	Link

@storybook/nextjs-vite

	Before	After	Difference
Dependency count	92	92	0
Self size	1.12 MB	1.12 MB	0 B
Dependency size	22.39 MB	22.43 MB	🚨 +37 KB 🚨
Bundle Size Analyzer	Link	Link

@storybook/react-native-web-vite

	Before	After	Difference
Dependency count	124	124	0
Self size	30 KB	30 KB	0 B
Dependency size	23.68 MB	23.72 MB	🚨 +37 KB 🚨
Bundle Size Analyzer	Link	Link

@storybook/react-vite

	Before	After	Difference
Dependency count	82	82	0
Self size	35 KB	35 KB	0 B
Dependency size	20.18 MB	20.21 MB	🚨 +37 KB 🚨
Bundle Size Analyzer	Link	Link

@storybook/react-webpack5

	Before	After	Difference
Dependency count	274	274	0
Self size	24 KB	24 KB	🚨 +12 B 🚨
Dependency size	44.54 MB	44.57 MB	🚨 +37 KB 🚨
Bundle Size Analyzer	Link	Link

@storybook/react

	Before	After	Difference
Dependency count	58	57	🎉 -1 🎉
Self size	1.19 MB	1.23 MB	🚨 +37 KB 🚨
Dependency size	13.20 MB	12.94 MB	🎉 -264 KB 🎉
Bundle Size Analyzer	Link	Link