Validate files with ESLint

npm install --save-dev grunt-eslint

require('load-grunt-tasks')(grunt);

grunt.initConfig({
	eslint: {
		target: ['file.js']
	}
});

grunt.registerTask('default', ['eslint']);

const noAlertRule = require('./conf/rules/no-alert');

grunt.initConfig({
	eslint: {
		options: {
			overrideConfigFile: 'conf/eslint.js',
			plugins: {
				noAlertRule
			}
		},
		target: ['file.js']
	}
});

const js = require('@eslint/js');

grunt.initConfig({
	eslint: {
		options: {
			extends: [js.configs.recommended]
		},
		target: ['file.js']
	}
});

grunt.initConfig({
	eslint: {
		options: {
			format: './node_modules/eslint-tap/index.js'
		},
		target: ['file.js']
	}
});

grunt.initConfig({
	eslint: {
		options: {
			outputFile: 'eslint-results.xml',
			format: 'checkstyle'
		},
		target: ['file.js']
	}
});

This will output in checkstyle format to both the console and eslint-results.xml. To suppress console output and only write to the file, add silent: true.

grunt.initConfig({
	eslint: {
		options: {
			flags: ['v10_config_lookup_from_file']
		},
		target: ['../project1/scripts/**/*.js']
	}
});

See the ESLint options.

In addition the following options are supported:

Type: array | object

Requires ESLint 9.22+

Shareable configs to extend.

Type: array

Feauture flags to pass to ESLint.

Type: string
Default: 'stylish'

The name of a built-in formatter or path to a custom one.

Some formatters you might find useful: eslint-json, eslint-tap.

Type: string
Default: ''

Output the report to a file. When specified, the report is written to both the console and the file unless silent is true.

Type: boolean
Default: false

Report errors only.

Type: boolean
Default: false

Suppress console output. When used with outputFile, only writes to the file.

Type: number
Default: -1 (Means no limit)

The number of warnings to trigger non-zero exit code.

Type: boolean
Default: true

Fail the build if ESLint found any errors.