webpack/lib/errors/UnusedAssetsWarning.js

Packs ECMAScript/CommonJs/AMD modules for the browser. Allows you to split your codebase into multiple bundles, which can be loaded on demand. Supports loaders to preprocess files, i.e. json, jsx, es7, css, less, ... and your custom stuff.

/*
	MIT License http://www.opensource.org/licenses/mit-license.php
	Author Alexander Akait @alexander-akait
*/

"use strict";

const WebpackError = require("./WebpackError");

/**
 * @typedef {object} UnusedAssetDetails
 * @property {string} name the module, by request
 * @property {number} size the bytes its file adds to the output
 */

class UnusedAssetsWarning extends WebpackError {
	/**
	 * Creates an instance of UnusedAssetsWarning.
	 * @param {UnusedAssetDetails[]} assets the assets nothing reads
	 * @param {number} total the bytes they add between them
	 */
	constructor(assets, total) {
		const list = assets
			.map((it) => `\n  ${it.name} (${it.size} bytes)`)
			.join("");

		super(
			`unused assets: ${total} bytes are emitted for ${assets.length === 1 ? "an import whose binding" : "imports whose bindings"} nothing reads:${list}\nThe import brings the file into the output but its value is never used, so the bytes ship for nothing. Drop the import, or write it as 'import "./file"' with no binding where the file is wanted on disk regardless — 'experiments.futureDefaults' already leaves those alone and drops these.\nFor more info visit https://webpack.js.org/guides/asset-modules/`
		);

		/** @type {string} */
		this.name = "UnusedAssetsWarning";
	}
}

module.exports = UnusedAssetsWarning;