Core: Correctly fallback to first detected vitest config file

[yannbf]

Closes #

What I did

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Testing

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  • bug: Internal changes that fixes incorrect behavior.
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Summary by CodeRabbit

• Bug Fixes
  • Improved Vitest configuration discovery to correctly determine the workspace root directory when configuration files are present.

[nx-cloud]

View your CI Pipeline Execution ↗ for commit 394c8a8

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☁️ Nx Cloud last updated this comment at 2026-02-18 10:48:37 UTC

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

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📝 Walkthrough

Walkthrough

In the Vitest config discovery process within vitest-manager.ts, the assignment of firstVitestConfig has been modified to store the directory path of the located config file instead of the file path itself, thereby adjusting the directory used for the fallback root determination.

Changes

Cohort / File(s)	Summary
Vitest Config Discovery code/addons/vitest/src/node/vitest-manager.ts	Modified config discovery logic to store the config file's directory instead of the file path in firstVitestConfig, affecting the fallback root location determination.

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~3 minutes

Possibly related PRs

• storybookjs/storybook#33814 — Also modifies vitest-manager.ts to change directory-based root selection for Vitest config discovery.

✨ Finishing Touches

• 📝 Generate docstrings

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[storybook-app-bot]

Package Benchmarks

^{Commit: 394c8a8, ran on 18 February 2026 at 10:48:18 UTC}

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

@storybook/nextjs-vite

	Before	After	Difference
Dependency count	94	92	🎉 -2 🎉
Self size	1.12 MB	1.12 MB	0 B
Dependency size	23.51 MB	22.34 MB	🎉 -1.17 MB 🎉
Bundle Size Analyzer	Link	Link

@storybook/react-native-web-vite

	Before	After	Difference
Dependency count	126	124	🎉 -2 🎉
Self size	30 KB	30 KB	🚨 +18 B 🚨
Dependency size	24.80 MB	23.62 MB	🎉 -1.17 MB 🎉
Bundle Size Analyzer	Link	Link

@storybook/react-vite

	Before	After	Difference
Dependency count	84	82	🎉 -2 🎉
Self size	35 KB	35 KB	0 B
Dependency size	21.29 MB	20.12 MB	🎉 -1.17 MB 🎉
Bundle Size Analyzer	Link	Link