stylelint/lib/utils/validateTypes.mjs

A mighty CSS linter that helps you avoid errors and enforce conventions.

import { isPlainObject as _isPlainObject } from 'is-plain-object';

/** @import { Range, Position } from 'stylelint' */

/**
 * Checks if the value is a boolean or a Boolean object.
 * @param {unknown} value
 * @returns {value is boolean}
 */
export function isBoolean(value) {
	return typeof value === 'boolean' || value instanceof Boolean;
}

/**
 * Checks if the value is a function or a Function object.
 * @param {unknown} value
 * @returns {value is Function}
 */
export function isFunction(value) {
	return typeof value === 'function' || value instanceof Function;
}

/**
 * Checks if the value is *nullish*.
 * @see https://developer.mozilla.org/en-US/docs/Glossary/Nullish
 * @param {unknown} value
 * @returns {value is null | undefined}
 */
export function isNullish(value) {
	return value == null;
}

/**
 * Checks if the value is a number or a Number object.
 * @param {unknown} value
 * @returns {value is number}
 */
export function isNumber(value) {
	return typeof value === 'number' || value instanceof Number;
}

/**
 * Checks if the value is an object.
 * @param {unknown} value
 * @returns {value is object}
 */
export function isObject(value) {
	return value !== null && typeof value === 'object';
}

/**
 * Checks if the value is a regular expression.
 * @param {unknown} value
 * @returns {value is RegExp}
 */
export function isRegExp(value) {
	return value instanceof RegExp;
}

/**
 * Checks if the value is a string or a String object.
 * @param {unknown} value
 * @returns {value is string}
 */
export function isString(value) {
	return typeof value === 'string' || value instanceof String;
}

/**
 * Checks if the value is a plain object.
 * @param {unknown} value
 * @returns {value is Record<string, unknown>}
 */
export function isPlainObject(value) {
	return _isPlainObject(value);
}

/**
 * Assert that the value is truthy.
 * @param {unknown} value
 * @param {string} [message]
 * @returns {asserts value}
 */
export function assert(value, message = undefined) {
	if (message) {
		// eslint-disable-next-line no-console
		console.assert(value, message);
	} else {
		// eslint-disable-next-line no-console
		console.assert(value);
	}
}

/**
 * Assert that the value is a function or a Function object.
 * @param {unknown} value
 * @returns {asserts value is Function}
 */
export function assertFunction(value) {
	// eslint-disable-next-line no-console
	console.assert(isFunction(value), `"${value}" must be a function`);
}

/**
 * Assert that the value is a number or a Number object.
 * @param {unknown} value
 * @returns {asserts value is number}
 */
export function assertNumber(value) {
	// eslint-disable-next-line no-console
	console.assert(isNumber(value), `"${value}" must be a number`);
}

/**
 * Assert that the value is a string or a String object.
 * @param {unknown} value
 * @returns {asserts value is string}
 */
export function assertString(value) {
	// eslint-disable-next-line no-console
	console.assert(isString(value), `"${value}" must be a string`);
}

/**
 * @param {unknown} value
 * @returns {value is Position}
 */
export function isPosition(value) {
	if (!isPlainObject(value)) return false;

	if (!isNumber(value.line)) return false;

	if (!isNumber(value.column)) return false;

	return true;
}

/**
 * @param {unknown} value
 * @returns {value is Range}
 */
export function isRange(value) {
	if (!isPlainObject(value)) return false;

	if (!isPosition(value.start)) return false;

	if (!isPosition(value.end)) return false;

	return true;
}