eslint-svelte3-preprocess/README.md

svelte preprocess for eslint-plugin-svelte3

### ESLint plugin Svelte Preprocessor

## Purpose

It's a preprocessor to use with
[`eslint-plugin-svelte3`](https://github.com/sveltejs/eslint-plugin-svelte3) to
produce AST valid to the original code.

For now only TypeScript is supported but the idea is to add Coffeescript and Pug
support, like the
[`svelte-preprocess`](https://github.com/sveltejs/svelte-preprocess) package.

Many thanks to [Conduitry](https://github.com/Conduitry) and her/his initial
work on her/his [fork](https://github.com/Conduitry/eslint-plugin-svelte3).

## Install

```
pnpm i -D eslint-svelte3-preprocess
```

## Usage

x After following the docs of
[`eslint-plugin-svelte3`](https://github.com/sveltejs/eslint-plugin-svelte3) to
configure your `eslintrc.js` file, you will need to add some props required by
[@typescript-eslint/parser](https://github.com/typescript-eslint/typescript-eslint/tree/master/packages/parser)
and finally import your `svelte.config` file (if you would like to use the same
configuration) and call the `elint-plugin-svelte3-preprocess` passing your
preprocess as a parameter.

This is a example that works!

```js
const eslintSveltePreprocess = require("eslint-svelte3-preprocess");
const svelteConfig = require("./svelte.config");

module.exports = {
    parserOptions: {
        ecmaVersion: 2019,
        sourceType: "module",
    },
    parser: "@typescript-eslint/parser",
    env: {
        es6: true,
        browser: true,
    },
    extends: ["eslint:recommended", "plugin:@typescript-eslint/recommended"],
    plugins: ["svelte3", "@typescript-eslint"],
    overrides: [
        {
            files: ["*.svelte"],
            processor: "svelte3/svelte3",
        },
    ],
    settings: {
        "svelte3/preprocess": eslintSveltePreprocess(svelteConfig.preprocess),
    },
};
```

## Editor support

I only tested it on Visual Studio Code, but I guess it should be similar for
other editors. If you find the way to solve it, I would appreciate your
collaboration to improve this documentation.

### Visual Studio Code

Having
[Svelte for VS Code](https://marketplace.visualstudio.com/items?itemName=svelte.svelte-vscode)
and
[ESLint](https://marketplace.visualstudio.com/items?itemName=dbaeumer.vscode-eslint)
extensions, you need to add this to your configuration.

```json
{
    "eslint.validate": ["svelte"]
}
```