@stylistic/stylelint-plugin/lib/rules/value-list-max-empty-lines/index.js

A collection of stylistic/formatting Stylelint rules

import stylelint from "stylelint"

import { addNamespace } from "../../utils/addNamespace/index.js"
import { getDeclarationValue } from "../../utils/getDeclarationValue/index.js"
import { getRuleDocUrl } from "../../utils/getRuleDocUrl/index.js"
import { isNumber } from "../../utils/validateTypes/index.js"
import { setDeclarationValue } from "../../utils/setDeclarationValue/index.js"

let { utils: { report, ruleMessages, validateOptions } } = stylelint

let shortName = `value-list-max-empty-lines`

export let ruleName = addNamespace(shortName)

export let messages = ruleMessages(ruleName, {
	expected: (max) => `Expected no more than ${max} empty ${max === 1 ? `line` : `lines`}`,
})

export let meta = {
	url: getRuleDocUrl(shortName),
	fixable: true,
}

/** @type {import('stylelint').Rule} */
function rule (primary) {
	let maxAdjacentNewlines = primary + 1

	return (root, result) => {
		let validOptions = validateOptions(result, ruleName, {
			actual: primary,
			possible: isNumber,
		})

		if (!validOptions) {
			return
		}

		let violatedCRLFNewLinesRegex = new RegExp(`(?:\r\n){${maxAdjacentNewlines + 1},}`)
		let violatedLFNewLinesRegex = new RegExp(`\n{${maxAdjacentNewlines + 1},}`)
		let allowedLFNewLinesString = `\n`.repeat(maxAdjacentNewlines)
		let allowedCRLFNewLinesString = `\r\n`.repeat(maxAdjacentNewlines)

		root.walkDecls((decl) => {
			let value = getDeclarationValue(decl)

			if (violatedLFNewLinesRegex.test(value) || violatedCRLFNewLinesRegex.test(value)) {
				report({
					message: messages.expected,
					messageArgs: [primary],
					node: decl,
					index: 0,
					endIndex: 0,
					result,
					ruleName,
					fix () {
						let newValueString = value
							.replace(new RegExp(violatedLFNewLinesRegex, `gm`), allowedLFNewLinesString)
							.replace(new RegExp(violatedCRLFNewLinesRegex, `gm`), allowedCRLFNewLinesString)

						setDeclarationValue(decl, newValueString)
					},
				})
			}
		})
	}
}

rule.ruleName = ruleName
rule.messages = messages
rule.meta = meta

export default rule