webpack/lib/dependencies/HarmonyCompatibilityDependency.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 { UsageState } = require("../ExportsInfo");
const InitFragment = require("../InitFragment");
const RuntimeGlobals = require("../RuntimeGlobals");
const makeSerializable = require("../util/makeSerializable");
const NullDependency = require("./NullDependency");

/** @typedef {import("webpack-sources").ReplaceSource} ReplaceSource */
/** @typedef {import("../Dependency")} Dependency */
/** @typedef {import("../DependencyTemplate").DependencyTemplateContext} DependencyTemplateContext */
/** @typedef {import("../Module")} Module */

class HarmonyCompatibilityDependency extends NullDependency {
	get type() {
		return "harmony export header";
	}
}

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

HarmonyCompatibilityDependency.Template = class HarmonyExportDependencyTemplate extends (
	NullDependency.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,
		{
			module,
			runtimeTemplate,
			moduleGraph,
			initFragments,
			runtimeRequirements,
			runtime,
			concatenationScope
		}
	) {
		if (concatenationScope) return;
		const exportsInfo = moduleGraph.getExportsInfo(module);
		if (
			exportsInfo.getReadOnlyExportInfo("__esModule").getUsed(runtime) !==
			UsageState.Unused
		) {
			const content = runtimeTemplate.defineEsModuleFlagStatement({
				exportsArgument: module.exportsArgument,
				runtimeRequirements
			});
			initFragments.push(
				new InitFragment(
					content,
					InitFragment.STAGE_HARMONY_EXPORTS,
					0,
					"harmony compatibility"
				)
			);
		}
		if (moduleGraph.isAsync(module)) {
			runtimeRequirements.add(RuntimeGlobals.module);
			runtimeRequirements.add(RuntimeGlobals.asyncModule);
			initFragments.push(
				new InitFragment(
					runtimeTemplate.supportsArrowFunction()
						? `${RuntimeGlobals.asyncModule}(${module.moduleArgument}, async (__webpack_handle_async_dependencies__) => {\n`
						: `${RuntimeGlobals.asyncModule}(${module.moduleArgument}, async function (__webpack_handle_async_dependencies__) {\n`,
					InitFragment.STAGE_ASYNC_BOUNDARY,
					0,
					undefined,
					module.buildMeta.async
						? `\n__webpack_handle_async_dependencies__();\n}, 1);`
						: "\n});"
				)
			);
		}
	}
};

module.exports = HarmonyCompatibilityDependency;