Output Minify Internal Exports - Rolldown

In-depth

For example, if you have the following code:

// main.js
import './lib.js';

// lib.js
import('./dynamic.js');
export const importantValue = 42;

// dynamic.js
import { importantValue } from './lib.js';
console.log(importantValue);

The output with minifyInternalExports: false will be:

// main.js
import('./dynamic-CCJ-yTfk.js');
const importantValue = 42;

export { importantValue };

// dynamic-CCJ-yTfk.js
import { importantValue } from './index.js';

console.log(importantValue);

On the other hand, the output with minifyInternalExports: true will be:

// main.js
import('./dynamic-CCJ-yTfk.js');
const importantValue = 42;

export { importantValue as t };

// dynamic-CCJ-yTfk.js
import { t as importantValue } from './index.js';

console.log(importantValue);

Even though it appears that setting this option to true makes the output larger, it actually makes it smaller if a minifier is used. In this case, export { importantValue as t } can become e.g., export{t as e} or even export{t}, while otherwise it would produce export{ a as importantValue } because a minifier usually will not change export signatures.