fix: handle decorators after type declarations

[Chakroun-Anas]

Issue: #20

Problem:

The parser crashes with Unexpected character '@' when a decorator appears immediately after an interface or type declaration, which is common in Angular and NestJS codebases.

Example:

interface User {
  id: number;
  name: string;
}

@Injectable()
export class UserService {
  getUser() { return null; }
}

Root cause

After parsing the interface closing }, the parser calls next() to advance to the @ character while still in type parsing mode. The getTokenFromCodeInType method didn't handle @ , causing it to fall through to the base parser which doesn't recognise decorators.

Solution

Added @ character handling in getTokenFromCodeInType method moving the position of the cursor and finishing by calling finishToken with the token type @

Testing

• All 188 tests pass (187 existing + 1 new)
• No breaking changes

[changeset-bot]

🦋 Changeset detected

Latest commit: e9ce73d

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@sveltejs/acorn-typescript	Patch

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[baseballyama]

@Chakroun-Anas Hi! Thank you for your PR! Can you add a changeset?

[Chakroun-Anas]

Hello @baseballyama,

changeset added, thank you!

[baseballyama]

Thank you for your contribution!

Since @ (64) does not appear in type declarations, I believe handling this issue in getTokenFromCodeInType is not appropriate.

I’ve submitted an alternative PR: #26

[manuel3108]

Closed in favor of #26