Solid ESLint Plugin

This package contains Solid-specific linting rules for ESLint. It can ease Solid's learning curve by finding and fixing problems around Solid's reactivity system, and can migrate some React patterns to Solid code.

It's approaching a 1.0.0 release, and it's well tested and should be helpful in Solid projects today.

• Installation
• Configuration
  • TypeScript
  • Manual Configuration
  • Flat Configuration
• Rules
• Troubleshooting
• Versioning

Installation

Install eslint and eslint-plugin-solid locally.

npm install --save-dev eslint eslint-plugin-solid
# or
pnpm add --save-dev eslint eslint-plugin-solid
yarn add --dev eslint eslint-plugin-solid

# optional, to create an ESLint config file
npx eslint --init
# or
pnpm eslint --init
yarn eslint --init

If you're using VSCode, you'll want to install the ESLint extension. You're encouraged to enable auto-fixing problems on save by adding the following to your settings.json file.

{
  "editor.codeActionsOnSave": {
    "source.fixAll": true
  }
}

If you're using Vite, you may want to install vite-plugin-eslint.

You may also want to check out eslint-plugin-jsx-a11y, which provides useful rules for writing accessible HTML.

Configuration

Use the "plugin:solid/recommended" configuration to get reasonable defaults as shown below.

{
  "plugins": ["solid"],
  "extends": ["eslint:recommended", "plugin:solid/recommended"]
}

TypeScript

If you're using TypeScript, use the "plugin:solid/typescript" configuration instead. This disables some features that overlap with type checking.

{
  "parser": "@typescript-eslint/parser",
  "plugins": ["solid"],
  "extends": ["eslint:recommended", "plugin:solid/typescript"]
}

Manual Configuration

If you don't want to use a preset, you can configure rules individually. Add the "solid" plugin, enable JSX with the parser options (or use the equivalent options for @typescript-eslint/parser or @babel/eslint-parser), and configure the rules you would like to use. Some rules have additional options you can set.

{
  "plugins": ["solid"],
  "parserOptions": {
    "ecmaFeatures": {
      "jsx": true
    }
  },
  "rules": {
    "solid/reactivity": "warn",
    "solid/no-destructure": "warn",
    "solid/jsx-no-undef": "error"
  }
}

Flat Configuration

ESLint's new configuration system, Flat Configuration, is available starting in ESLint v8.23.0. To use it, create an eslint.config.js file at the root of your project, instead of .eslintrc.* and/or .eslintignore.

import js from "@eslint/js";
import solid from "eslint-plugin-solid/configs/recommended";

export default [
  js.configs.recommended, // replaces eslint:recommended
  solid,
];

For TypeScript:

import js from "@eslint/js";
import solid from "eslint-plugin-solid/configs/typescript";
import * as tsParser from "@typescript-eslint/parser";

export default [
  js.configs.recommended,
  {
    files: ["**/*.{ts,tsx}"],
    ...solid,
    languageOptions: {
      parser: tsParser,
      parserOptions: {
        project: "tsconfig.json",
      },
    },
  },
];

These configurations do not configure global variables in ESLint. You can do this yourself manually or with a package like globals by creating a configuration with a languageOptions.globals object. We recommend setting up global variables for Browser APIs as well as at least ES2015.

Note for the ESLint VSCode Extension: Enable the "Use Flat Config" setting for your workspace to enable Flat Config support.

Flat configs are also available as plugin.configs['flat/recommended'] and plugin.configs['flat/typescript'], after using import plugin from 'eslint-plugin-solid'.

Rules

✔: Enabled in the recommended configuration.

🔧: Fixable with eslint --fix/IDE auto-fix.

✔	🔧	Rule	Description
✔	🔧	solid/components-return-once	Disallow early returns in components. Solid components only run once, and so conditionals should be inside JSX.
✔	🔧	solid/event-handlers	Enforce naming DOM element event handlers consistently and prevent Solid's analysis from misunderstanding whether a prop should be an event handler.
✔	🔧	solid/imports	Enforce consistent imports from "solid-js", "solid-js/web", and "solid-js/store".
✔		solid/jsx-no-duplicate-props	Disallow passing the same prop twice in JSX.
✔		solid/jsx-no-script-url	Disallow javascript: URLs.
✔	🔧	solid/jsx-no-undef	Disallow references to undefined variables in JSX. Handles custom directives.
✔		solid/jsx-uses-vars	Prevent variables used in JSX from being marked as unused.
		solid/no-array-handlers	Disallow usage of type-unsafe event handlers.
✔	🔧	solid/no-destructure	Disallow destructuring props. In Solid, props must be used with property accesses (props.foo) to preserve reactivity. This rule only tracks destructuring in the parameter list.
✔	🔧	solid/no-innerhtml	Disallow usage of the innerHTML attribute, which can often lead to security vulnerabilities.
		solid/no-proxy-apis	Disallow usage of APIs that use ES6 Proxies, only to target environments that don't support them.
✔	🔧	solid/no-react-deps	Disallow usage of dependency arrays in createEffect and createMemo.
✔	🔧	solid/no-react-specific-props	Disallow usage of React-specific className/htmlFor props, which were deprecated in v1.4.0.
✔		solid/no-unknown-namespaces	Enforce using only Solid-specific namespaced attribute names (i.e. 'on:' in <div on:click={...} />).
	🔧	solid/prefer-classlist	Enforce using the classlist prop over importing a classnames helper. The classlist prop accepts an object { [class: string]: boolean } just like classnames.
✔	🔧	solid/prefer-for	Enforce using Solid's <For /> component for mapping an array to JSX elements.
	🔧	solid/prefer-show	Enforce using Solid's <Show /> component for conditionally showing content. Solid's compiler covers this case, so it's a stylistic rule only.
✔		solid/reactivity	Enforce that reactivity (props, signals, memos, etc.) is properly used, so changes in those values will be tracked and update the view as expected.
✔	🔧	solid/self-closing-comp	Disallow extra closing tags for components without children.
✔	🔧	solid/style-prop	Require CSS properties in the style prop to be valid and kebab-cased (ex. 'font-size'), not camel-cased (ex. 'fontSize') like in React, and that property values with dimensions are strings, not numbers with implicit 'px' units.

Troubleshooting

The rules in this plugin provide sensible guidelines as well as possible, but there may be times where you know better than the rule and want to ignore a warning. To do that, add a comment like the following:

// eslint-disable-next-line solid/reactivity
const [editedValue, setEditedValue] = createSignal(props.value);

Please note: there may also be times where a rule correctly warns about a subtle problem, even if it looks like a false positive at first. With solid/reactivity, please look at the reactivity docs before deciding to disable the rule.

When in doubt, feel free to file an issue.

Versioning

Pre-1.0.0, the rules and the recommended and typescript configuations will be stable across patch (0.0.x) versions, but may change across minor (0.x) versions. If you want to pin a minor version, use a tilde in your package.json.

- "eslint-plugin-solid": "^0.14.3"
+ "eslint-plugin-solid": "~0.14.3"