Trouble with no-unused-vars rule

[tschaub]

Before You File a Bug Report Please Confirm You Have Done The Following...

• I have tried restarting my IDE and the issue persists.
• I have updated to the latest version of the packages.

What version of ESLint are you using?

v8.32.0

What version of eslint-plugin-astro are you using?

0.21.1

What did you do?

Configuration

{
  "extends": [
    "plugin:astro/recommended"
  ],
  "rules": {
    "no-unused-vars": "error"
  },
  "overrides": [
    {
      "files": [
        "*.astro"
      ],
      "parser": "astro-eslint-parser",
      "parserOptions": {
        "extraFileExtensions": [
          ".astro"
        ],
        "ecmaVersion": "latest"
      }
    }
  ]
}

---
import SomeComponent from '../components/SomeComponent.astro';
---

<SomeComponent />

What did you expect to happen?

I was hoping that the Astro plugin would work with the no-unused-vars rule.

What actually happened?

/path/to/src/pages/problem.astro
  2:8  error  'SomeComponent' is defined but never used  no-unused-vars

Link to Minimal Reproducible Example

https://stackblitz.com/edit/github-nzoac8?file=README.md

Additional comments

Much like the eslint-plugin-react allows ESLint rules (such as no-unused-vars) to work with JSX, I was hoping that this plugin would allow the same for Astro components. I see that there are integration tests using the no-unused-vars rule, but it looks like those don't cover the use of a variable from a component script in a component template.

[ota-meshi]

Thank you for the report.

It can be fixed by doing scope analysis in the parser. I will fix that.

[tschaub]

Thank you for the quick fix, @ota-meshi!

[tschaub]

@ota-meshi - I've just tried upgrading to the latest plugin and parser versions and this issue came up again (planetlabs/maps#501).

Let me know if I should open a new issue in the eslint-plugin-astro project or in astro-eslint-parser.

[tschaub]

I see that the regression was reported in #378