webpack/lib/dependencies/HarmonyImportBareSideEffectDependency.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 { ASSET_TYPE } = require("../ModuleSourceTypeConstants");
const makeSerializable = require("../util/makeSerializable");
const HarmonyImportSideEffectDependency = require("./HarmonyImportSideEffectDependency");

/** @import Module from "../Module" */
/** @import ModuleGraph from "../ModuleGraph" */
/** @import { GetConditionFn } from "../Dependency" */

/**
 * Whether a module is emitted as a file of its own, asked of the module so a
 * plugin emitting the same way is treated alike. `buildInfo.filename` cannot
 * serve here: generation sets it long after a connection has to know whether
 * it is active.
 * @param {Module} module the module to look up
 * @returns {boolean} true when it emits a file
 */
const emitsOwnFile = (module) => module.getSourceTypes().has(ASSET_TYPE);

/**
 * An `import "..."` that declares no binding. It is a separate class rather
 * than a flag so it costs nothing per instance, and the bound form — much the
 * more common one — keeps the base class and its inline caches untouched.
 */
class HarmonyImportBareSideEffectDependency extends HarmonyImportSideEffectDependency {
	/**
	 * Returns function to determine if the connection is active.
	 * @param {ModuleGraph} moduleGraph module graph
	 * @returns {null | false | GetConditionFn} function to determine if the connection is active
	 */
	getCondition(moduleGraph) {
		return (connection) => {
			const refModule = connection.resolvedModule;

			if (!refModule) return true;
			// Nothing reads the module, so emitting its file is the only thing the
			// import can have been written for.
			if (emitsOwnFile(refModule)) return true;

			return refModule.getSideEffectsConnectionState(moduleGraph);
		};
	}
}

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

HarmonyImportBareSideEffectDependency.Template =
	HarmonyImportSideEffectDependency.Template;

module.exports = HarmonyImportBareSideEffectDependency;