`@sveltejs/package` Allow disabling the default behavior of copying `package.json` to the output directory when packaging a Svelte library

[bryanmylee]

Describe the problem

For context, I'm building a cross-framework component library so I've set up a standard package structure for each framework in my monorepo with npm workspaces.

I'm using Vite with @sveltejs/package to develop and build my components. However, @sveltejs/package breaks my toolchain because it creates a copy of package.json in my dist folder.

npm workspaces picks up both the original package.json and dist/package.json, causing other dependent packages to break due to the duplication.

Describe the proposed solution

I rather keep my project structure and manage a single copy of package.json manually, so I'd like an option to disable the copy behavior.

This should ideally be added to svelte.config.js as a copyPackageJson option.

Alternatives considered

I've tried running a script to delete dist/package.json manually after each build, but this frequently breaks when Nx builds multiple packages concurrently due to the race condition.

Importance

would make my life easier

Additional Information

No response

[donmccurdy]

I'm here for the same issue — using Lerna (similar to Nx) to manage several packages within the same github repository. Because svelte-package moves the package.json file into the build directory, this creates problems requiring extra workarounds specifically for this package, which makes it harder to manage the repository as a whole.

[niktek]

Just to add another scenario for monorepos- our SK lib requires entries in the "exports" field of the dev version of package.json that point into /src/lib/xyz. svelte-package keeps these incorrect dev specific entries when it goes to make the published version with it's own generated "exports" entries and this results in a broken published package.

To work around this, we remove the "exports" field, let svelte-package do its thing and then re-insert those entries after the packaging.

Here is a repro https://github.com/niktek/minimono

in root, run:

pnpm i
pnpm dev

If you delete the "exports" key from /packages/skeleton/package.json it will crash the newsite project. And you can see the script workarounds being employed in that same file. If you do a raw svelte-package you will see those dev "exports" be carried over into the public package folder that will then result in a broken package being published.

[bryanmylee]

Quick bump on the PR to merge a fix for this issue:

#6864