eslint/lib/cli-engine/formatters/stylish.js

An AST-based pattern checker for JavaScript.

/**
 * @fileoverview Stylish reporter
 * @author Sindre Sorhus
 */
"use strict";

const chalk = require("chalk"),
	util = require("node:util"),
	table = require("../../shared/text-table");

//------------------------------------------------------------------------------
// Helpers
//------------------------------------------------------------------------------

/**
 * Given a word and a count, append an s if count is not one.
 * @param {string} word A word in its singular form.
 * @param {int} count A number controlling whether word should be pluralized.
 * @returns {string} The original word with an s on the end if count is not one.
 */
function pluralize(word, count) {
	return count === 1 ? word : `${word}s`;
}

//------------------------------------------------------------------------------
// Public Interface
//------------------------------------------------------------------------------

module.exports = function (results) {
	let output = "\n",
		errorCount = 0,
		warningCount = 0,
		fixableErrorCount = 0,
		fixableWarningCount = 0,
		summaryColor = "yellow";

	results.forEach(result => {
		const messages = result.messages;

		if (messages.length === 0) {
			return;
		}

		errorCount += result.errorCount;
		warningCount += result.warningCount;
		fixableErrorCount += result.fixableErrorCount;
		fixableWarningCount += result.fixableWarningCount;

		output += `${chalk.underline(result.filePath)}\n`;

		output += `${table(
			messages.map(message => {
				let messageType;

				if (message.fatal || message.severity === 2) {
					messageType = chalk.red("error");
					summaryColor = "red";
				} else {
					messageType = chalk.yellow("warning");
				}

				return [
					"",
					String(message.line || 0),
					String(message.column || 0),
					messageType,
					message.message.replace(/([^ ])\.$/u, "$1"),
					chalk.dim(message.ruleId || ""),
				];
			}),
			{
				align: ["", "r", "l"],
				stringLength(str) {
					return util.stripVTControlCharacters(str).length;
				},
			},
		)
			.split("\n")
			.map(el =>
				el.replace(/(\d+)\s+(\d+)/u, (m, p1, p2) =>
					chalk.dim(`${p1}:${p2}`),
				),
			)
			.join("\n")}\n\n`;
	});

	const total = errorCount + warningCount;

	if (total > 0) {
		output += chalk[summaryColor].bold(
			[
				"\u2716 ",
				total,
				pluralize(" problem", total),
				" (",
				errorCount,
				pluralize(" error", errorCount),
				", ",
				warningCount,
				pluralize(" warning", warningCount),
				")\n",
			].join(""),
		);

		if (fixableErrorCount > 0 || fixableWarningCount > 0) {
			output += chalk[summaryColor].bold(
				[
					"  ",
					fixableErrorCount,
					pluralize(" error", fixableErrorCount),
					" and ",
					fixableWarningCount,
					pluralize(" warning", fixableWarningCount),
					" potentially fixable with the `--fix` option.\n",
				].join(""),
			);
		}
	}

	// Resets output color, for prevent change on top level
	return total > 0 ? chalk.reset(output) : "";
};