## Summary
I have no idea what I'm doing with the fix (all the interesting stuff is
in the second commit).
The basic problem is the compiler emits the diagnostic:
```
x: "foobar"
^^^^^^
```
Which the suppression code-action hands the end of to `Tokens::after`
which then panics because that function panics if handed an offset that
is in the middle of a token.
Fixes https://github.com/astral-sh/ty/issues/1748
## Test Plan
Many tests added (only the e2e test matters).
Previously, the code action to do auto-import on a pre-existing symbol
assumed that the auto-importer would always generate an import
statement. But sometimes an import statement already exists.
A good example of this is the following snippet:
```
import warnings
@deprecated
def myfunc(): pass
```
Specifically, `deprecated` exists in `warnings` but isn't currently
imported. A code action to fix this could feasibly do two
transformations here. One is:
```
import warnings
@warnings.deprecated
def myfunc(): pass
```
Another is:
```
from warnings import deprecated
import warnings
@deprecated
def myfunc(): pass
```
The existing auto-import infrastructure chooses the former, since it
reuses a pre-existing import statement. But this PR chooses the latter
for the case of a code action. I'm not 100% sure this is the correct
choice, but it seems to defer more strongly to what the user has typed.
That is, that they want to use it unqualified because it's what has been
typed. So we should add the necessary import statement to make that
work.
Fixesastral-sh/ty#1668
## Summary
Originally I planned to feed this in as a `fix` but I realized that we
probably don't want to be trying to resolve import suggestions while
we're doing type inference. Thus I implemented this as a fallback when
there's no fixes on a diagnostic, which can use the full lsp machinery.
Fixes https://github.com/astral-sh/ty/issues/1552
## Test Plan
Works in the IDE, added some e2e tests.
## Summary
This PR adds a code action to remove unused ignore comments.
This PR also includes some infrastructure boilerplate to set up code
actions in the editor:
* Extend `snapshot-diagnostics` to render fixes
* Render fixes when using `--output-format=full`
* Hook up edits and the code action request in the LSP
* Add the `Unnecessary` tag to `unused-ignore-comment` diagnostics
* Group multiple unused codes into a single diagnostic
The same fix can be used on the CLI once we add `ty fix`
Note: `unused-ignore-comment` is currently disabled by default.
https://github.com/user-attachments/assets/f9e21087-3513-4156-85d7-a90b1a7a3489
Dhruv Manilawala
Aria Desires
Micha Reiser
Andrew Gallant