source: frontend/node_modules/webpack/lib/dependencies/ImportDependency.js

/*
        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 { ImportPhaseUtils } = require("./ImportPhase");
const ModuleDependency = require("./ModuleDependency");

/** @typedef {import("webpack-sources").ReplaceSource} ReplaceSource */
/** @typedef {import("../AsyncDependenciesBlock")} AsyncDependenciesBlock */
/** @typedef {import("../Dependency").RawReferencedExports} RawReferencedExports */
/** @typedef {import("../Dependency").ReferencedExports} ReferencedExports */
/** @typedef {import("../DependencyTemplate").DependencyTemplateContext} DependencyTemplateContext */
/** @typedef {import("../Module")} Module */
/** @typedef {import("../Module").BuildMeta} BuildMeta */
/** @typedef {import("../ModuleGraph")} ModuleGraph */
/** @typedef {import("../javascript/JavascriptParser").ImportAttributes} ImportAttributes */
/** @typedef {import("../javascript/JavascriptParser").Range} Range */
/** @typedef {import("../serialization/ObjectMiddleware").ObjectDeserializerContext} ObjectDeserializerContext */
/** @typedef {import("../serialization/ObjectMiddleware").ObjectSerializerContext} ObjectSerializerContext */
/** @typedef {import("../util/runtime").RuntimeSpec} RuntimeSpec */
/** @typedef {import("./ImportPhase").ImportPhaseType} ImportPhaseType */

class ImportDependency extends ModuleDependency {
        /**
         * Creates an instance of ImportDependency.
         * @param {string} request the request
         * @param {Range} range expression range
         * @param {RawReferencedExports | null} referencedExports list of referenced exports
         * @param {ImportPhaseType} phase import phase
         * @param {ImportAttributes=} attributes import attributes
         */
        constructor(request, range, referencedExports, phase, attributes) {
                super(request);
                this.range = range;
                this.referencedExports = referencedExports;
                this.phase = phase;
                this.attributes = attributes;
        }

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

        get category() {
                return "esm";
        }

        /**
         * Returns an identifier to merge equal requests.
         * @returns {string | null} an identifier to merge equal requests
         */
        getResourceIdentifier() {
                let str = super.getResourceIdentifier();
                // We specifically use this check to avoid writing the default (`evaluation` or `0`) value and save memory
                if (this.phase) {
                        str += `|phase${ImportPhaseUtils.stringify(this.phase)}`;
                }
                if (this.attributes) {
                        str += `|attributes${JSON.stringify(this.attributes)}`;
                }
                return str;
        }

        /**
         * 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 {ReferencedExports} referenced exports
         */
        getReferencedExports(moduleGraph, runtime) {
                if (!this.referencedExports) return Dependency.EXPORTS_OBJECT_REFERENCED;
                /** @type {ReferencedExports} */
                const refs = [];
                for (const referencedExport of this.referencedExports) {
                        if (referencedExport[0] === "default") {
                                const selfModule =
                                        /** @type {Module} */
                                        (moduleGraph.getParentModule(this));
                                const importedModule =
                                        /** @type {Module} */
                                        (moduleGraph.getModule(this));
                                const exportsType = importedModule.getExportsType(
                                        moduleGraph,
                                        /** @type {BuildMeta} */
                                        (selfModule.buildMeta).strictHarmonyModule
                                );
                                if (
                                        exportsType === "default-only" ||
                                        exportsType === "default-with-named"
                                ) {
                                        return Dependency.EXPORTS_OBJECT_REFERENCED;
                                }
                        }
                        refs.push({
                                name: referencedExport,
                                canMangle: false
                        });
                }
                return refs;
        }

        /**
         * Serializes this instance into the provided serializer context.
         * @param {ObjectSerializerContext} context context
         */
        serialize(context) {
                context.write(this.range);
                context.write(this.referencedExports);
                context.write(this.phase);
                context.write(this.attributes);
                super.serialize(context);
        }

        /**
         * Restores this instance from the provided deserializer context.
         * @param {ObjectDeserializerContext} context context
         */
        deserialize(context) {
                this.range = context.read();
                this.referencedExports = context.read();
                this.phase = context.read();
                this.attributes = context.read();
                super.deserialize(context);
        }
}

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

ImportDependency.Template = class ImportDependencyTemplate extends (
        ModuleDependency.Template
) {
        /**
         * Applies the plugin by registering its hooks on the compiler.
         * @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)
                );
                let content = runtimeTemplate.moduleNamespacePromise({
                        chunkGraph,
                        block,
                        module: /** @type {Module} */ (moduleGraph.getModule(dep)),
                        request: dep.request,
                        strict: /** @type {BuildMeta} */ (module.buildMeta).strictHarmonyModule,
                        dependency: dep,
                        message: "import()",
                        runtimeRequirements
                });

                // For source phase imports, unwrap the default export
                // import.source() should return the source directly, not a namespace
                if (ImportPhaseUtils.isSource(dep.phase)) {
                        content = `${content}.then(${runtimeTemplate.returningFunction(
                                'm["default"]',
                                "m"
                        )})`;
                }

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

module.exports = ImportDependency;