Vitest : cannot find package 'rollup'

While trying to execute unit tests with Vitest through Yarn in my Angular app I have an error about 'rollup' package :

yarn run test
[INFO] failed to load config from xxx\angular-test\vitest.config.ts
[INFO] An unhandled exception occurred: Cannot find package 'rollup' imported from xxx\angular-test\.yarn\__virtual__\vite-virtual-35af3c8a63\13\Users\wwww\AppData\Local\Yarn\Berry\cache\vite-npm-6.3.5-244c1b4d55-10c0.zip\node_modules\vite\dist\node\index.js
[INFO] Did you mean to import "rollup/dist/parseAst.js"?


Context:

• Node : v22.13.0
• Yarn : 4.9.2 (with default PNP mode)
• Angular : 20.0.3
• Vite : 7.0.0 / Vitest : 3.2.4

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