Why should we bundle dependencies when using lib mode?

[ianzone]

I found that vite bundles all dependencies into one file when building a library, but why should we do that since the lib and its dependencies are bundled in the final project? Also, the bundled lib can't share the project's dependencies, doesn't it?

[hi-ogawa]

That might not be intuitive, but that's somewhat known convention and it's required to set rollupOptions.external manually. See the doc saying https://vite.dev/guide/build.html#library-mode

Make sure to also externalize any dependencies that you do not want to bundle into your library, e.g. vue or react:

In rollup, people commonly reuse package.json's dependencies as external such as

vite/packages/vite/rollup.config.ts

Lines 115 to 116 in 56a86ae

	...Object.keys(pkg.dependencies),
	...Object.keys(pkg.peerDependencies),

[ianzone]

Then how about having an option not to get bundlers involved? Like build.bundle: false