jshint

What is jshint?

JSHint is a static code analysis tool used in software development for checking if JavaScript source code complies with coding rules. It helps developers identify potential errors and enforce coding standards.

What are jshint's main functionalities?

Basic Linting

This feature allows you to perform basic linting on a piece of JavaScript code. The code sample demonstrates how to use JSHint to check a simple JavaScript snippet for errors.

const jshint = require('jshint').JSHINT;
const code = 'var a = 1;';
const options = { esversion: 6 };
jshint(code, options);
console.log(jshint.errors);

Custom Configuration

JSHint allows you to customize the linting process with various options. This example shows how to enable the 'undef' option to check for the use of undefined variables.

const jshint = require('jshint').JSHINT;
const code = 'var a = 1;';
const options = { esversion: 6, undef: true };
jshint(code, options);
console.log(jshint.errors);

Using JSHint with Configuration File

You can use a configuration file (e.g., .jshintrc) to define your linting rules. This example demonstrates how to read a JavaScript file and a JSHint configuration file, then lint the code using the specified rules.

const fs = require('fs');
const jshint = require('jshint').JSHINT;
const code = fs.readFileSync('path/to/your/file.js', 'utf8');
const config = JSON.parse(fs.readFileSync('.jshintrc', 'utf8'));
jshint(code, config);
console.log(jshint.errors);

Other packages similar to jshint

eslint

ESLint is another popular JavaScript linting tool that is highly configurable and supports custom rules. It provides more flexibility and a larger ecosystem of plugins compared to JSHint.

jscs

JSCS (JavaScript Code Style) is a code style linter for JavaScript. It focuses more on enforcing coding style conventions rather than finding potential errors. It has been merged with ESLint, but older versions are still in use.

tslint

TSLint is a linter for TypeScript, which is a superset of JavaScript. It provides similar functionality to JSHint but is specifically designed for TypeScript code. TSLint is now deprecated in favor of ESLint with TypeScript support.

README

node-jshint

A command line interface and npm package for jshint.

Install

To use jshint from any location (for npm v1.x) you need to install using the global (-g) flag.

npm install -g jshint

Usage

The command line interface looks like this.

jshint path path2 [options]

You can also require JSHint itself as a module.

var jshint = require('jshint');

Note: If you are using npm v1.x be sure to install jshint locally (without the -g flag) or link it globally.

Custom Reporters

Specify a custom reporter module (see example/reporter.js).

--reporter path/to/reporter.js

Use a jslint compatible xml reporter.

--jslint-reporter

Custom Options

Specify custom lint options (see example/config.json).

--config path/to/config.json

Note: This bypasses any .jshintrc files.

Default Options

The CLI uses the default options that come with JSHint. However, if it locates a .jshintrc file in your home directory (~/) it will use those options first.

Per Directory Options

If there is a .jshintrc file in the current working directory, any of those options will take precedence over (or be merged with) any options found in the ~/.jshintrc file (if it exists).

Installing dependencies for development

npm install argparser jasmine-node
git submodule init
git submodule update

Running Tests

jake test