webpack/lib/dependencies/ImportDependency.js

Packs CommonJs/AMD modules for the browser. Allows to split your codebase into multiple bundles, which can be loaded on demand. Support 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 Dependency = require("../Dependency");
const makeSerializable = require("../util/makeSerializable");
const ModuleDependency = require("./ModuleDependency");

/** @typedef {import("webpack-sources").ReplaceSource} ReplaceSource */
/** @typedef {import("../AsyncDependenciesBlock")} AsyncDependenciesBlock */
/** @typedef {import("../Dependency").ReferencedExport} ReferencedExport */
/** @typedef {import("../DependencyTemplate").DependencyTemplateContext} DependencyTemplateContext */
/** @typedef {import("../ModuleGraph")} ModuleGraph */
/** @typedef {import("../util/runtime").RuntimeSpec} RuntimeSpec */

class ImportDependency extends ModuleDependency {
	/**
	 * @param {string} request the request
	 * @param {[number, number]} range expression range
	 * @param {string[][]=} referencedExports list of referenced exports
	 */
	constructor(request, range, referencedExports) {
		super(request);
		this.range = range;
		this.referencedExports = referencedExports;
	}

	get type() {
		return "import()";
	}

	get category() {
		return "esm";
	}

	/**
	 * Returns list of exports referenced by this dependency
	 * @param {ModuleGraph} moduleGraph module graph
	 * @param {RuntimeSpec} runtime the runtime for which the module is analysed
	 * @returns {(string[] | ReferencedExport)[]} referenced exports
	 */
	getReferencedExports(moduleGraph, runtime) {
		return this.referencedExports
			? this.referencedExports.map(e => ({
					name: e,
					canMangle: false
			  }))
			: Dependency.EXPORTS_OBJECT_REFERENCED;
	}

	serialize(context) {
		context.write(this.range);
		context.write(this.referencedExports);
		super.serialize(context);
	}

	deserialize(context) {
		this.range = context.read();
		this.referencedExports = context.read();
		super.deserialize(context);
	}
}

makeSerializable(ImportDependency, "webpack/lib/dependencies/ImportDependency");

ImportDependency.Template = class ImportDependencyTemplate extends (
	ModuleDependency.Template
) {
	/**
	 * @param {Dependency} dependency the dependency for which the template should be applied
	 * @param {ReplaceSource} source the current replace source which can be modified
	 * @param {DependencyTemplateContext} templateContext the context object
	 * @returns {void}
	 */
	apply(
		dependency,
		source,
		{ runtimeTemplate, module, moduleGraph, chunkGraph, runtimeRequirements }
	) {
		const dep = /** @type {ImportDependency} */ (dependency);
		const block = /** @type {AsyncDependenciesBlock} */ (
			moduleGraph.getParentBlock(dep)
		);
		const content = runtimeTemplate.moduleNamespacePromise({
			chunkGraph,
			block: block,
			module: moduleGraph.getModule(dep),
			request: dep.request,
			strict: module.buildMeta.strictHarmonyModule,
			message: "import()",
			runtimeRequirements
		});

		source.replace(dep.range[0], dep.range[1] - 1, content);
	}
};

module.exports = ImportDependency;