Diagnostics don't refresh after file rename

[mjbvz]

1. Start with two files:

// index.ts
import { foo } from './abc';

// xyz.ts
export const foo = 1;

2. Confirm you see an error about missing abc file in index.ts
3. Now rename xyz.ts to abc.ts

Bug
Sometimes I still see the error. I have to reload the server to get the error to go away

If you don't see this, try renaming the file a few times

Here's a log from when it happened: rename-bug.log

[lukeapage]

Maybe #2133