[!] (plugin commonjs--resolver) RollupError: Identifier "fn" has already been declared

[coderaiser]

Rollup Version

4.4.0

Operating System (or Browser)

mac os

Node Version (if applicable)

v20.9.0

Link To Reproduction

https://github.com/putoutjs/bundle

Expected Behaviour

Build without errors

Actual Behaviour

Everything works good with Rollup v4.3.1

[sapphi-red]

Umm, it seems the error comes from this part.
https://github.com/FredKSchott/rollup-plugin-polyfill-node/blob/eb507a21ad82236255988548dea6120d7a277de2/polyfills/util.js#L588-L640

minimal repro: 1, 2

acorn doesn't throw an error

[lukastaegert]

Interesting. So this forbidden:

var fn;
function fn(){};

but this is allowed:

function foo() {
  var fn;
  function fn(){};
}

So if I understand this, the reasoning is that inside a function, the var is hoisted beyond the body scope maybe into the "parameter scope", which is why function and var in the second example are not considered to be in the same scope.

[lazka]

I'm getting the same error since the update from 4.3.1 to 4.4.0:

[!] (plugin commonjs--resolver) RollupError: Identifier "Vt" has already been declared
node_modules/jspdf/dist/jspdf.es.min.js (236:40507)

let me know if I should provide more info.

[github-actions]

This issue has been resolved via #5248 as part of rollup@4.4.1. You can test it via npm install rollup.