Flattening imports MUST take care of javascript reserved words

[matthiasg]

• Rollup Version: v1.2.2
• Operating System (or Browser): Windows 10
• Node Version: 10.15.0

How Do We Reproduce?

See https://github.com/matthiasg/rollup-reserved-word-issue/

Basically importing like this import * as express from 'express' and then using express.static does not work since the call is flattened to just static which is a reserved word.

Expected Behavior

The resulting file should either leave the module.static call or rename static to a non-reserved word

Actual Behavior

index.js → stdout...
[!] Error: The keyword 'static' is reserved
module.js (1:16)
1: export function static(text) {
                   ^
2:   console.log(text)
3: }
Error: The keyword 'static' is reserved
    at error (C:\Users\mgt57\AppData\Roaming\npm-cache\_npx\12096\node_modules\rollup\dist\rollup.js:3597:30)
    at Module.error (C:\Users\mgt57\AppData\Roaming\npm-cache\_npx\12096\node_modules\rollup\dist\rollup.js:14376:9)
    at tryParse (C:\Users\mgt57\AppData\Roaming\npm-cache\_npx\12096\node_modules\rollup\dist\rollup.js:14039:16)
    at Module.setSource (C:\Users\mgt57\AppData\Roaming\npm-cache\_npx\12096\node_modules\rollup\dist\rollup.js:14095:35)
    at C:\Users\mgt57\AppData\Roaming\npm-cache\_npx\12096\node_modules\rollup\dist\rollup.js:17409:20
    at process._tickCallback (internal/process/next_tick.js:68:7)
    at Function.Module.runMain (internal/modules/cjs/loader.js:745:11)
    at findNodeScript.then.existing (C:\Users\mgt57\AppData\Roaming\npm\node_modules\npm\node_modules\libnpx\index.js:268:14)

index.js

import * as module from './module'

module.static('test')

module.js

export function static(text) {
  console.log(text)
}

[gund]

I hit same bug rendering compiled bundles broken.

Here is simple example.

I'm using io-ts library inside my own library and it has exports named undefined and null.

While undefined is being renamed to undefined$1, null is kept not renamed so generated code is invalid.

NOTE: This is only a bug while emitting in esm and systemjs format.

[matthiasg]

BTW: Workaround right now is a little involved.

in my case

const staticPropertyName = 'static'
express[staticPropertyName](...)

It has to be indirected via a variable, calling express['static'] gets resolved and renaming on import as in import { static as renamedStatic } from 'express' also gets resolved and thus doesn't work.

[lukastaegert]

Hi, thanks for this issue. As a matter of fact, I am currently working on a complete revamp of the variable resolution/deconflicting logic where it would be easy to incorporate these fixes. Will still take a little while, though.

[lukastaegert]

Possible fix a #2689