Add more flexibility when using `workspace` feature

[jpzwarte]

Clear and concise description of the problem

Sometimes you have a bunch of packages in a workspace, but not all packages share the same exports. Example: you have a folder with a bunch of UI components and a "shared" package. That shared package is different from the others.

You can't have "optional entries": if you include an entrypoint and the shared package doesn't have it, it errors out.

At the moment i can work around that by either using the inputOptions callback or the exports.customExports callback.

Suggested solution

It would be nice if you could have package specific config options in package.json of that package. tsdown would then include those package specific options when building the package in the workspace. Perhaps something like:

"tsdown": {
  "exports": {
    "customExports": {
        "./foo.js": "./src/foo.js"
    }
  }
}

Alternative

No response

Additional context

No response

Validations

• Follow our Code of Conduct
• Read the Contributing Guide.
• Check that there isn't already an issue that request the same feature to avoid creating a duplicate.

[sxzz]

I think we already supported this feature. If not working, please provide a minimal reproduction.

[jpzwarte]

I think we already supported this feature. If not working, please provide a minimal reproduction.

Thanks, i'll give it a try. I couldn't find anything in the documentation about it.

Edit, nm i found it: "Additionally, you can define your configuration directly in the tsdown field of your package.json file."

[jpzwarte]

@sxzz I do have some minor issues:

In this example, i have "./hohoho.js": "./src/hohoho.ts" as the "source". tsdown keeps the .ts extension for ths publishConfig.

  "publishConfig": {
    "exports": {
      ".": "./dist/index.js",
      "./package.json": "./package.json",
      "./hohoho.js": "./src/hohoho.ts"
    }
  },
  "exports": {
    ".": "./src/index.ts",
    "./package.json": "./package.json",
    "./hohoho.js": "./src/hohoho.ts"
  },
  "tsdown": {
    "entry": [
      "src/index.ts"
    ],
    "exports": {
      "customExports": {
        "./hohoho.js": "./src/hohoho.ts"
      }
    }
  }

Second issue is this:

tsdown.config.js:

  workspace: 'packages/*',
  entry: [
    'src/index.ts',
    { 'register.js': 'src/register.ts' }
  ],

package.json after running tsdown:

  "publishConfig": {
    "exports": {
      ".": "./dist/index.js",
      "./register.js": "./dist/register.js.js",
      "./package.json": "./package.json"
    }
  },
  "exports": {
    ".": "./src/index.ts",
    "./register.js": "./src/register.ts",
    "./package.json": "./package.json"
  }

Notice the double .js extension.

Is it ok to keep these issues here, or should i file (separate) new ones?