webpack/lib/library/ModuleLibraryPlugin.js

/*
	MIT License http://www.opensource.org/licenses/mit-license.php
	Author Tobias Koppers @sokra
*/

"use strict";

const { ConcatSource } = require("webpack-sources");
const RuntimeGlobals = require("../RuntimeGlobals");
const Template = require("../Template");
const ConcatenatedModule = require("../optimize/ConcatenatedModule");
const propertyAccess = require("../util/propertyAccess");
const AbstractLibraryPlugin = require("./AbstractLibraryPlugin");

/** @typedef {import("webpack-sources").Source} Source */
/** @typedef {import("../../declarations/WebpackOptions").LibraryOptions} LibraryOptions */
/** @typedef {import("../../declarations/WebpackOptions").LibraryType} LibraryType */
/** @typedef {import("../Chunk")} Chunk */
/** @typedef {import("../Compilation").ChunkHashContext} ChunkHashContext */
/** @typedef {import("../Compiler")} Compiler */
/** @typedef {import("../Module")} Module */
/** @typedef {import("../Module").BuildMeta} BuildMeta */
/** @typedef {import("../javascript/JavascriptModulesPlugin").StartupRenderContext} StartupRenderContext */
/** @typedef {import("../util/Hash")} Hash */

/**
 * @template T
 * @typedef {import("./AbstractLibraryPlugin").LibraryContext<T>} LibraryContext<T>
 */

/**
 * @typedef {object} ModuleLibraryPluginOptions
 * @property {LibraryType} type
 */

/**
 * @typedef {object} ModuleLibraryPluginParsed
 * @property {string} name
 * @property {string | string[]=} export
 */

/**
 * @typedef {ModuleLibraryPluginParsed} T
 * @extends {AbstractLibraryPlugin<ModuleLibraryPluginParsed>}
 */
class ModuleLibraryPlugin extends AbstractLibraryPlugin {
	/**
	 * @param {ModuleLibraryPluginOptions} options the plugin options
	 */
	constructor(options) {
		super({
			pluginName: "ModuleLibraryPlugin",
			type: options.type
		});
	}

	/**
	 * Apply the plugin
	 * @param {Compiler} compiler the compiler instance
	 * @returns {void}
	 */
	apply(compiler) {
		super.apply(compiler);

		compiler.hooks.compilation.tap("ModernModuleLibraryPlugin", compilation => {
			const { exportsDefinitions } =
				ConcatenatedModule.getCompilationHooks(compilation);
			exportsDefinitions.tap(
				"ModernModuleLibraryPlugin",
				(definitions, module) => {
					// If we have connections not all modules were concatenated, so we need the wrapper
					const connections =
						compilation.moduleGraph.getIncomingConnections(module);

					for (const connection of connections) {
						if (connection.originModule) {
							return false;
						}
					}

					// Runtime and splitting chunks now requires the wrapper too
					for (const chunk of compilation.chunkGraph.getModuleChunksIterable(
						module
					)) {
						if (!chunk.hasRuntime()) {
							return false;
						}
					}

					return true;
				}
			);
		});
	}

	/**
	 * @param {LibraryOptions} library normalized library option
	 * @returns {T | false} preprocess as needed by overriding
	 */
	parseOptions(library) {
		const { name } = library;
		if (name) {
			throw new Error(
				`Library name must be unset. ${AbstractLibraryPlugin.COMMON_LIBRARY_NAME_MESSAGE}`
			);
		}
		const _name = /** @type {string} */ (name);
		return {
			name: _name,
			export: 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,
		{ moduleGraph, chunk },
		{ options, compilation }
	) {
		const result = new ConcatSource(source);
		const exportsInfos = options.export
			? [
					moduleGraph.getExportInfo(
						module,
						Array.isArray(options.export) ? options.export[0] : options.export
					)
				]
			: moduleGraph.getExportsInfo(module).orderedExports;
		const definitions =
			/** @type {BuildMeta} */
			(module.buildMeta).exportsFinalName || {};
		const shortHandedExports = [];
		const exports = [];
		const isAsync = moduleGraph.isAsync(module);

		if (isAsync) {
			result.add(
				`${RuntimeGlobals.exports} = await ${RuntimeGlobals.exports};\n`
			);
		}

		for (const exportInfo of exportsInfos) {
			if (!exportInfo.provided) continue;

			let shouldContinue = false;

			const reexport = exportInfo.findTarget(moduleGraph, _m => true);

			if (reexport) {
				const exp = moduleGraph.getExportsInfo(reexport.module);

				for (const reexportInfo of exp.orderedExports) {
					if (
						reexportInfo.provided === false &&
						reexportInfo.name === /** @type {string[]} */ (reexport.export)[0]
					) {
						shouldContinue = true;
					}
				}
			}

			if (shouldContinue) continue;

			const webpackExportsProperty = exportInfo.getUsedName(
				exportInfo.name,
				chunk.runtime
			);
			const definition =
				definitions[/** @type {string} */ (webpackExportsProperty)];
			const finalName =
				definition ||
				`${RuntimeGlobals.exports}${Template.toIdentifier(exportInfo.name)}`;

			if (!definition) {
				result.add(
					`var ${finalName} = ${RuntimeGlobals.exports}${propertyAccess([
						/** @type {string} */
						(exportInfo.getUsedName(exportInfo.name, chunk.runtime))
					])}\n`
				);
			}

			if (finalName && (finalName.includes(".") || finalName.includes("["))) {
				exports.push([exportInfo.name, finalName]);
			} else {
				shortHandedExports.push(
					definition && finalName === exportInfo.name
						? finalName
						: `${finalName} as ${exportInfo.name}`
				);
			}
		}

		if (shortHandedExports.length > 0) {
			result.add(`export { ${shortHandedExports.join(", ")} };\n`);
		}

		for (const [exportName, final] of exports) {
			result.add(
				`export ${compilation.outputOptions.environment.const ? "const" : "var"} ${exportName} = ${final};\n`
			);
		}

		return result;
	}
}

module.exports = ModuleLibraryPlugin;