cjs format should not replace "exports.default =" to "module.exports = " when "exports.default =" in last line

[gaoletian]

a reproduction or simple code @pi0

https://github.com/gaoletian/mkdist-issues-192

// src/Foo.ts
export enum Type {
    Foo,
    Bar
}

export default class Action {}

// dist/Foo.js
"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
module.exports = exports.Type = void 0;
var Type = exports.Type = /* @__PURE__ */(Type2 => {
  Type2[Type2["Foo"] = 0] = "Foo";
  Type2[Type2["Bar"] = 1] = "Bar";
  return Type2;
})(Type || {});
class Action {}
module.exports = Action;

// test.js
const foo = require('./dist/Foo');
console.log(foo);
console.log(foo.Type);

$ node test.js
foo =  [class Action]
foo.Type = undefined

Hi! 👋

Firstly, thanks for your work on this project! 🙂

Today I used patch-package to patch [email protected] for the project I'm working on.

Here is the diff that solved my problem:

diff --git a/node_modules/mkdist/dist/index.mjs b/node_modules/mkdist/dist/index.mjs
index 1403db8..7b1582a 100644
--- a/node_modules/mkdist/dist/index.mjs
+++ b/node_modules/mkdist/dist/index.mjs
@@ -59,7 +59,9 @@ const jsLoader = async (input, { options }) => {
   }
   const isCjs = options.format === "cjs";
   if (isCjs) {
-    contents = jiti("").transform({ source: contents, retainLines: false }).replace(/^exports.default = /gm, "module.exports = ").replace(/^var _default = exports.default = /gm, "module.exports = ").replace("module.exports = void 0;", "");
+    contents = jiti("")
+      .transform({ source: contents, retainLines: false })
+      .replace("module.exports = void 0;", "");
   }
   let extension = isCjs ? ".js" : ".mjs";
   if (options.ext) {

This issue body was partially generated by patch-package.

[pi0]

Hi dear @gaoletian. The syntax change is intentional to fix issues with certain bundlers. Would you please share your case which replacing exports.default to module.exports make issues? (a reproduction or simple code) 🙏🏼

[gaoletian]

a reproduction or simple code

https://github.com/gaoletian/mkdist-issues-192

[pi0]

Thanks for making reproduction and sorry for checking late.

For reference, this was the original hotfix 94444df to address IPX/Unstorage regression with .cjs bundling as a result of a behavior change in Jiti (babel) changes that broke Netlify builder.

[email protected]/drivers/fs.cjs (before - fine) > [email protected]/drivers/fs.cjs (problematic) > [email protected]/drivers/fs.cjs (fixed with hotfix)

I will see if can find smaller workaround only for that case and also working with your reproduction 👍🏼