[publint] `publishConfig.exports` is used for linting by warning message uses value from root's `exports`

[timofei-iatsenko]

Reproduction link or steps

With a given package.json file

  "exports": {
    ".": "./src/index.ts"
  },
  "publishConfig": {
    "exports": {
      ".": "./dist/index.mjs"
    }
  },

Imagine we don't have ./dist/index.mjs file on the disk, the publint correctly report an issue, but the warning message is using data from the normal exports

The repro is here https://github.com/timofei-iatsenko/tsdown-publint-issue-repro

What is expected?

Warning message uses message from publishConfig.exports

ERROR [publint] pkg.exports["."] is ./dist/index.mjs but the file does not exist.

What is actually happening?

The warning message is using data from the normal exports, not from the publishConfig.exports

ERROR [publint] pkg.exports["."] is ./src/index.ts but the file does not exist.

So actually ./src/index.ts exists, but /dist/index.mjs is not. The warning message makes it confusing

Any additional comments?

This happend only when publint invoked from the tsdown. When publint is used from it's own cli - reporting is correct.

[bluwy]

I think this can be fixed by also getting the pkg here:

tsdown/src/features/pkg/publint.ts

Lines 38 to 41 in daed0cd

	const { messages } = await publint({
	...options.publint,
	pack: { tarball: tarball.buffer },
	})

And pass it to:

tsdown/src/features/pkg/publint.ts

Line 55 in daed0cd

const formattedMessage = formatMessage(message, options.pkg)

The pkg would be from the tarball so it's more accurate. pkg is only returned since publint v0.3.8 though, so it would likely still need the options.pkg fallback.