Unused code is left when minifying

[just-boris]

When a constant value imported from a different module, it is not inlined properly. Reproducible in the online playground.

import { isDevelopment } from "./is-development";

export function devWarning() {
 if(isDevelopment) {
   console.log('test')
 }
}

export function run() {
  devWarning('dev only');
}

is-development.js contents

export const isDevelopment = false; 
// does not work either 
// export const isDevelopment = process.env.NODE_ENV !== "production";

The output still contains an unused function: function o(){!1}. Expected to eliminate all this code, as it happens in a single file setup