What is @eslint/js?
@eslint/js is a package that provides the core functionality of ESLint, a popular JavaScript linter. It allows developers to analyze their JavaScript code to find and fix problems based on a set of rules. The package is highly configurable and can be extended with custom rules and plugins.
What are @eslint/js's main functionalities?
Linting JavaScript Code
This code demonstrates how to use @eslint/js to lint JavaScript files in the 'src' directory. It initializes an ESLint instance, lints the files, formats the results using the 'stylish' formatter, and prints the formatted results.
const { ESLint } = require('@eslint/js');
(async function main() {
const eslint = new ESLint();
const results = await eslint.lintFiles(['src/**/*.js']);
const formatter = await eslint.loadFormatter('stylish');
const resultText = formatter.format(results);
console.log(resultText);
})();
Custom Configuration
This code shows how to use @eslint/js with a custom configuration. It sets specific rules to enforce no console statements and require semicolons at the end of statements.
const { ESLint } = require('@eslint/js');
(async function main() {
const eslint = new ESLint({
overrideConfig: {
rules: {
'no-console': 'error',
'semi': ['error', 'always']
}
}
});
const results = await eslint.lintFiles(['src/**/*.js']);
const formatter = await eslint.loadFormatter('stylish');
const resultText = formatter.format(results);
console.log(resultText);
})();
Using Plugins
This code demonstrates how to use @eslint/js with the React plugin. It configures ESLint to use rules specific to React, such as ensuring that React variables are used correctly in JSX files.
const { ESLint } = require('@eslint/js');
(async function main() {
const eslint = new ESLint({
overrideConfig: {
plugins: ['react'],
rules: {
'react/jsx-uses-react': 'error',
'react/jsx-uses-vars': 'error'
}
}
});
const results = await eslint.lintFiles(['src/**/*.jsx']);
const formatter = await eslint.loadFormatter('stylish');
const resultText = formatter.format(results);
console.log(resultText);
})();
Other packages similar to @eslint/js
jshint
JSHint is another popular JavaScript linter that helps to detect errors and potential problems in JavaScript code. Unlike ESLint, JSHint is less configurable and has fewer rules and plugins available.
standard
Standard is a JavaScript style guide, linter, and formatter all in one. It enforces a specific coding style without the need for configuration. While it is simpler to use, it is less flexible compared to ESLint.
prettier
Prettier is an opinionated code formatter that supports many languages, including JavaScript. It focuses on code formatting rather than linting for errors. Prettier can be used alongside ESLint to handle code style issues.
ESLint JavaScript Plugin
Website | Configure ESLint | Rules | Contributing | Twitter | Chatroom
The beginnings of separating out JavaScript-specific functionality from ESLint.
Right now, this plugin contains two configurations:
recommended
- enables the rules recommended by the ESLint team (the replacement for "eslint:recommended"
)all
- enables all ESLint rules (the replacement for "eslint:all"
)
Installation
npm install @eslint/js -D
Usage
Use in your eslint.config.js
file anytime you want to extend one of the configs:
import js from "@eslint/js";
export default [
{
files: ["**/*.js"],
rules: js.configs.recommended.rules
},
{
files: ["**/*.js"],
rules: {
...js.configs.recommended.rules,
"no-unused-vars": "warn"
}
},
{
files: ["**/*.js"],
rules: {
...js.configs.all.rules,
"no-unused-vars": "warn"
}
}
]
License
MIT