Auto-fix incorrect commas in `use` list

[nk9]

Today, this code is auto-fixed:

use sqlx::{PgPool, };
use std::path::{Path, PathBuf, };

The correct replacement is:

use sqlx::PgPool;
use std::path::{Path, PathBuf};

But the following code results in parse errors and is not auto-fixed by rust-analyzer:

use sqlx::{, PgPool};
use std::path::{Path, , PathBuf};

It is always possible to remove stray/duplicate commas and any number of spaces in use directives like this to produce correct code. In almost every circumstance, this will be what the user intended. I don't think it's necessary to attempt to properly parse a use without curly braces, that seems much more fraught. But I often find myself wanting to remove an import I no longer need, and I have to take the extra step of removing the comma too, despite the intention being unambiguous once the symbol is gone.

[ChayimFriedman2]

We don't actually fix the code, rustfmt does that, and it does not work with incorrect code.

[nk9]

Ah, apologies, I'll have a look in that repo instead.

[nk9]

@rustbot transfer rustfmt

[rustbot]

Only team members may use the transfer command.

[nk9]

I'd like to have this be in the correct repo. Would appreciate a transfer.

[lnicola]

@rustbot transfer rustfmt

[ytmimi]

There's no way rustfmt can reformat the code because it doesn't parse to begin with. rustfmt uses the rustc parser so you'd need to make changes to the compiler if you want to get your input to parse properly.

error: expected identifier, found `,`
 --> <stdin>:1:12
  |
1 | use sqlx::{, PgPool};
  |            ^ expected identifier
  |
help: remove this comma
  |
1 - use sqlx::{, PgPool};
1 + use sqlx::{ PgPool};
  |

error: expected identifier, found `,`
 --> <stdin>:2:23
  |
2 | use std::path::{Path, , PathBuf};
  |                       ^ expected identifier
  |
help: remove this comma
  |
2 - use std::path::{Path, , PathBuf};
2 + use std::path::{Path,  PathBuf};
  |