Core: Add support for wrapped components in component transformer

[yannbf]

Closes #

What I did

The component transformer was not account for components like memo(() => </>) so this PR fixes that.
See tests for example cases.

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

See tests

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 publish.yml --field pr=<PR_NUMBER>

Summary by CodeRabbit

Release Notes

• New Features

  • Added support for wrapped component default exports (e.g., components exported via wrapper functions).
  • Improved test generation for wrapped exports with proper metadata handling.

• Tests

  • Added comprehensive test coverage for wrapped export scenarios.

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☁️ Nx Cloud last updated this comment at 2026-01-19 09:56:13 UTC

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☁️ Nx Cloud last updated this comment at 2026-01-19 09:38:52 UTC

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☁️ Nx Cloud last updated this comment at 2026-01-19 09:45:42 UTC

[coderabbitai]

📝 Walkthrough

Walkthrough

The changes add support for handling wrapped default exports (e.g., export default someWrapper(Component)) in the CSF vitest plugin's component transformer. The transformer now detects CallExpression default exports, hoists them to const declarations, and generates appropriate test scaffolding. A corresponding test case validates this behavior.

Changes

Cohort / File(s)	Summary
Component Transformer Implementation code/core/src/csf-tools/vitest-plugin/component-transformer.ts	Adds logic to detect and handle default exports that are CallExpressions. Generates a unique identifier from the file name, creates a const wrapper variable, replaces the export default with the identifier, and registers the component. Notes that JSX detection is not performed for wrapped exports.
Component Transformer Tests code/core/src/csf-tools/vitest-plugin/component-transformer.test.ts	Introduces new test case "generates tests for wrapped exports" that verifies the transformer correctly hoists wrapped default exports (e.g., someWrapper(Component)) to const declarations, preserves the export, and generates vitest/storybook test blocks with inline snapshots for wrapped named exports.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~20 minutes

Possibly related PRs

• storybookjs/storybook#33479: Directly extends the same component-transformer implementation with handling and tests for wrapped default exports.

✨ Finishing touches

• 📝 Generate docstrings

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[storybook-app-bot]

Package Benchmarks

^{Commit: a614c73, ran on 19 January 2026 at 09:56:47 UTC}

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

@storybook/react-native-web-vite

	Before	After	Difference
Dependency count	159	159	0
Self size	30 KB	30 KB	🎉 -10 B 🎉
Dependency size	23.00 MB	23.12 MB	🚨 +115 KB 🚨
Bundle Size Analyzer	Link	Link

@storybook/cli

	Before	After	Difference
Dependency count	183	183	0
Self size	775 KB	775 KB	🚨 +139 B 🚨
Dependency size	67.38 MB	67.46 MB	🚨 +74 KB 🚨
Bundle Size Analyzer	Link	Link

@storybook/codemod

	Before	After	Difference
Dependency count	176	176	0
Self size	30 KB	30 KB	🎉 -40 B 🎉
Dependency size	65.95 MB	66.03 MB	🚨 +74 KB 🚨
Bundle Size Analyzer	Link	Link