Rolldown: 1.0.0-beta.52

In rollup, static flags (imported from another file) can be tree-shaken correctly.

Example: (stackblitz)

// src/flags.js
export const flag = false;

// src/index.js
import { flag } from './flags.js';

if (flag) {
  console.log('should not see me in bundle!');
} else {
  console.log('flag is false correctly');
}

Rollup bundle:

{
  console.log('flag is false correctly');
}

Rolldown bundle:

//#region src/flags.js
const flag = false;

//#endregion
//#region src/index.js
if (flag) console.log("should not see me in bundle!");
else console.log("flag is false correctly");

//#endregion

More context:

• This works as intended when the const flag is in the same file
• Nitro v3 relies on this for tree-shaking server internals, and currently, tree-shaking is not effective with rolldown/rolldown-vite, causing lots of unnecessary code to be bundled. If it is a non goal of rolldown for any reason we might consider alternative methods like static code replacement.