TS error when using imported Command type

[marcopetreri]

As described in the example below I cannot use Command type in types definitions because of this error:

Exported variable 'getBuildCommand' has or is using name 'local.Command' from external module "***/node_modules/commander/typings/index" but cannot be named

Example

import { Command } from 'commander';

export const getBuildCommand = (
   ...
) => (project: string, cmd: Command) => { ... };

[shadowspawn]

I was not able to reproduce this with typescript 3.6.2 and this program fragment. Someone else might recognise the error, or you could add some more context.

[fson]

I have made a minimal repoducible example for this issue: https://github.com/fson/commander-ts-repro.

When you compile the code using npm run build, it results in the following errror:

index.ts:3:1 - error TS4082: Default export of the module has or is using private name 'local.Command'.

[fson]

I also found a workaround: in some cases, the error went away after changing the exported function from an arrow function like this:

export default (program: Command) => { 

to a function expression:

export default function(program: Command) {

[shadowspawn]

Reproduced issue, and workaround, from @fson. (Thanks!)

Still trying to make sense of the local namespace pattern being used in the Commander definitions file.

[shadowspawn]

I've had a go at reworking the TypeScript declaration file and fixed this error, but the changes are tricky. If any TypeScript experts see this then a review of #1081 would be very welcome.

[shadowspawn]

Fixed in Commander v4, which has been released.

[shadowspawn]

I was reproducing this again and a historical note. This issue can be reproduced using TypeScript 3.8.3, but is fixed from 3.9.2.