I think yes, we should create a global variable declaration in eslint-scope for implicit globals, that's how just JS works.

Ping @eslint/eslint-team

We should consider whether assignment to an implicit global should create a global variable declaration in eslint-scope

I think it shouldn't, for several reasons:

1. Implicit globals are a legacy feature that should be avoided (e.g., it doesn't work in strict mode), so I think there's not much value in tracking something that should ideally be removed from the code. Also, nowadays it's rare to write non-strict code, which is the only code where this can work.
2. This would be a breaking change for consumers, including ESLint. Given the previous point, I think making a breaking change isn't justified.
3. These variables can already be found in global scope's implicit if anyone needs them.
4. Unlike declared variables, which are always created in the scope, these variables are created at the time when the assignment is executed, so they may or may not exist. That might be the reason why they were not already tracked in the global scope.

• These variables can already be found in global scope's implicit if anyone needs them.

I didn't realize these were tracked separately. In that case, I agree, we don't need to make any changes.

We should document this in the README for safekeeping.