Vitest: Create "Component Coverage" per story file

[valentinpalkovic]

We need to implement a mechanism in Vitest to generate coverage reports for each story file. This task focuses on collecting coverage data for all affected files when a story file is executed, and outputting the data in a parseable format. This will serve as the foundation for integrating coverage data into the Storybook UI or server at a later stage.

Tasks:

Configure Vitest for Coverage Reporting:

• Set up Vitest to collect coverage data for story files.
• Ensure that the configuration includes all necessary options for detailed coverage metrics (statements, branches, functions, lines).

Generate Coverage Reports:

Modify the Vitest configuration to generate coverage reports in a parseable format (e.g., JSON, LCOV). Ensure the reports include detailed coverage information for all affected files related to the story file being tested.

(Optional) Save Coverage Data:

Implement a mechanism to save the generated coverage reports in a structured format in a predefined directory. Ensure the saved data is organized and accessible for later use.

Documentation:

Document the process and configuration steps required to generate coverage reports with Vitest. Provide examples of the generated coverage data format for reference.

Acceptance Criteria:

• Vitest is configured to collect and generate detailed coverage reports for each story file.
• Coverage reports are outputted in a parseable format (e.g., JSON, LCOV) and saved in a predefined directory.
• The process and configuration steps are documented clearly, with examples of the coverage data format.

[greptile-apps[bot]]

Disclaimer This information might be inaccurate, due to it being generated automatically

1. Modify summarizeIndex in /code/core/src/core-server/utils/summarizeIndex.test.ts to include component coverage data.
2. Create a new utility function similar to extractComponentDescription in /code/renderers/svelte/src/docs/extractComponentDescription.test.ts to extract component coverage information.
3. Update CLI tools in /code/lib/cli-storybook and /code/lib/cli-sb to support the new component coverage feature.

References

/code/core/src/core-server/utils/summarizeIndex.test.ts /code/renderers/svelte/src/docs/extractComponentDescription.test.ts /code/lib/cli-storybook /code/lib/cli-sb

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[valentinpalkovic]

Completed. Except of the optional "(Optional) Save Coverage Data" requirement.