Typescript auto-import put comma in wrong position

[chengB12]

TypeScript Version: 4.1.0-dev.20200823
Visual Studio Code Version: 1.48.1

Search Terms: import comma

Code

import { Foo1,
   Foo2, Foo3,
   Foo4, Foo5,
} from 'foo'

export default {
     foo6: {} as Foo6
}

Expected behavior:
When prompted Quick Fix => click "Add 'Foo6' to existing import declaration 'foo', and click auto-import
The import declaration shall be

import { Foo1,
   Foo2, Foo3,
   Foo4, Foo5, Foo6,
} from 'foo'

Actual behavior:

import { Foo1,
   Foo2, Foo3,
   Foo4, Foo5,, Foo6
} from 'foo'

[chengB12]

This is can be reproduced when new imported is last thing in that line, when '} from 'foo' is on newline, and having a trailing comma.

It looks like auto-import didn't consider trailing comma:

import {
   foo1
} from 'foo'
// ==>
import {
   foo1, foo2
} from 'foo'

without trailing comma, auto-import does thing exactly correct, however, with trailing comma, it will wrong format

[j-oliveras]

Duplicated/related to #39717?

[chengB12]

Duplicated/related to #39717?

Yes, it looks duplicate, I think because I searched for open issues, and that issue was closed, so I missed that.

And previous closed because can't reproduce, I find a way to reproduce

[andrewbranch]

I don’t know what to tell you 😐

[chengB12]

well, I can conform ts 4.1.0-dev.20200824, vs code 1.48.2 still has this issue

[chengB12]

I reproduced it with 11 imports:

import {
    Foo1, Foo2,
    Foo3,
    Foo4,
    Foo5,
    Foo6,
    Foo7,
    Foo8,
    Foo9,
    Foo10,, Foo11
} from './foo'

export default {
    foo1: 1 as Foo1,
    foo2: 2 as Foo2,
    foo11: 11 as Foo11,
}

[chengB12]

before

after

[andrewbranch]

Ok, that one repros for me. Thanks @chengB12