webpack/lib/library/ExportPropertyLibraryPlugin.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 Tobias Koppers @sokra
*/

"use strict";

const { ConcatSource } = require("webpack-sources");
const { UsageState } = require("../ExportsInfo");
const RuntimeGlobals = require("../RuntimeGlobals");
const { propertyAccess } = require("../util/property");
const { getEntryRuntime } = require("../util/runtime");
const AbstractLibraryPlugin = require("./AbstractLibraryPlugin");

/** @typedef {import("webpack-sources").Source} Source */
/** @typedef {import("../../declarations/WebpackOptions").LibraryOptions} LibraryOptions */
/** @typedef {import("../../declarations/WebpackOptions").LibraryType} LibraryType */
/** @typedef {import("../../declarations/WebpackOptions").LibraryExport} LibraryExport */
/** @typedef {import("../Chunk")} Chunk */
/** @typedef {import("../Module")} Module */
/** @typedef {import("../Module").RuntimeRequirements} RuntimeRequirements */
/** @typedef {import("../javascript/JavascriptModulesPlugin").StartupRenderContext} StartupRenderContext */
/**
 * Defines the shared type used by this module.
 * @template T
 * @typedef {import("./AbstractLibraryPlugin").LibraryContext<T>} LibraryContext<T>
 */

/**
 * Defines the export property library plugin parsed type used by this module.
 * @typedef {object} ExportPropertyLibraryPluginParsed
 * @property {LibraryExport=} export
 */

/**
 * Defines the export property library plugin options type used by this module.
 * @typedef {object} ExportPropertyLibraryPluginOptions
 * @property {LibraryType} type
 */
/**
 * Represents the export property library plugin runtime component.
 * @typedef {ExportPropertyLibraryPluginParsed} T
 * @extends {AbstractLibraryPlugin<ExportPropertyLibraryPluginParsed>}
 */
class ExportPropertyLibraryPlugin extends AbstractLibraryPlugin {
	/**
	 * Creates an instance of ExportPropertyLibraryPlugin.
	 * @param {ExportPropertyLibraryPluginOptions} options options
	 */
	constructor({ type }) {
		super({
			pluginName: "ExportPropertyLibraryPlugin",
			type
		});
	}

	/**
	 * Returns preprocess as needed by overriding.
	 * @param {LibraryOptions} library normalized library option
	 * @returns {T} preprocess as needed by overriding
	 */
	parseOptions(library) {
		return {
			export: library.export
		};
	}

	/**
	 * Finish entry module.
	 * @param {Module} module the exporting entry module
	 * @param {string} entryName the name of the entrypoint
	 * @param {LibraryContext<T>} libraryContext context
	 * @returns {void}
	 */
	finishEntryModule(
		module,
		entryName,
		{ options, compilation, compilation: { moduleGraph } }
	) {
		const runtime = getEntryRuntime(compilation, entryName);
		if (options.export) {
			const exportsInfo = moduleGraph.getExportInfo(
				module,
				Array.isArray(options.export) ? options.export[0] : options.export
			);
			exportsInfo.setUsed(UsageState.Used, runtime);
			exportsInfo.canMangleUse = false;
		} else {
			const exportsInfo = moduleGraph.getExportsInfo(module);
			exportsInfo.setUsedInUnknownWay(runtime);
		}
		moduleGraph.addExtraReason(module, "used as library export");
	}

	/**
	 * Processes the provided chunk.
	 * @param {Chunk} chunk the chunk
	 * @param {RuntimeRequirements} set runtime requirements
	 * @param {LibraryContext<T>} libraryContext context
	 * @returns {void}
	 */
	runtimeRequirements(chunk, set, libraryContext) {
		set.add(RuntimeGlobals.exports);
	}

	/**
	 * Renders source with library export.
	 * @param {Source} source source
	 * @param {Module} module module
	 * @param {StartupRenderContext} renderContext render context
	 * @param {LibraryContext<T>} libraryContext context
	 * @returns {Source} source with library export
	 */
	renderStartup(source, module, renderContext, { options }) {
		if (!options.export) return source;
		const postfix = `${RuntimeGlobals.exports} = ${
			RuntimeGlobals.exports
		}${propertyAccess(
			Array.isArray(options.export) ? options.export : [options.export]
		)};\n`;
		return new ConcatSource(source, postfix);
	}
}

module.exports = ExportPropertyLibraryPlugin;