webpack/lib/dependencies/RequireEnsureDependency.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 Tobias Koppers @sokra
*/

"use strict";

const RuntimeGlobals = require("../RuntimeGlobals");
const makeSerializable = require("../util/makeSerializable");
const NullDependency = require("./NullDependency");

/** @typedef {import("webpack-sources").ReplaceSource} ReplaceSource */
/** @typedef {import("../AsyncDependenciesBlock")} AsyncDependenciesBlock */
/** @typedef {import("../Dependency")} Dependency */
/** @typedef {import("../DependencyTemplate").DependencyTemplateContext} DependencyTemplateContext */
/** @typedef {import("../javascript/JavascriptParser").Range} Range */
/** @typedef {import("../serialization/ObjectMiddleware").ObjectDeserializerContext} ObjectDeserializerContext */
/** @typedef {import("../serialization/ObjectMiddleware").ObjectSerializerContext} ObjectSerializerContext */

class RequireEnsureDependency extends NullDependency {
	/**
	 * Creates an instance of RequireEnsureDependency.
	 * @param {Range} range range
	 * @param {Range} contentRange content range
	 * @param {Range | false} errorHandlerRange error handler range
	 */
	constructor(range, contentRange, errorHandlerRange) {
		super();

		this.range = range;
		this.contentRange = contentRange;
		this.errorHandlerRange = errorHandlerRange;
	}

	get type() {
		return "require.ensure";
	}

	/**
	 * Serializes this instance into the provided serializer context.
	 * @param {ObjectSerializerContext} context context
	 */
	serialize(context) {
		const { write } = context;

		write(this.range);
		write(this.contentRange);
		write(this.errorHandlerRange);

		super.serialize(context);
	}

	/**
	 * Restores this instance from the provided deserializer context.
	 * @param {ObjectDeserializerContext} context context
	 */
	deserialize(context) {
		const { read } = context;

		this.range = read();
		this.contentRange = read();
		this.errorHandlerRange = read();

		super.deserialize(context);
	}
}

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

RequireEnsureDependency.Template = class RequireEnsureDependencyTemplate extends (
	NullDependency.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, moduleGraph, chunkGraph, runtimeRequirements }
	) {
		const dep = /** @type {RequireEnsureDependency} */ (dependency);
		const depBlock = /** @type {AsyncDependenciesBlock} */ (
			moduleGraph.getParentBlock(dep)
		);
		const promise = runtimeTemplate.blockPromise({
			chunkGraph,
			block: depBlock,
			message: "require.ensure",
			runtimeRequirements
		});
		const range = dep.range;
		const contentRange = dep.contentRange;
		const errorHandlerRange = dep.errorHandlerRange;
		source.replace(range[0], contentRange[0] - 1, `${promise}.then((`);
		if (errorHandlerRange) {
			source.replace(
				contentRange[1],
				errorHandlerRange[0] - 1,
				`).bind(null, ${RuntimeGlobals.require}))['catch'](`
			);
			source.replace(errorHandlerRange[1], range[1] - 1, ")");
		} else {
			source.replace(
				contentRange[1],
				range[1] - 1,
				`).bind(null, ${RuntimeGlobals.require}))['catch'](${RuntimeGlobals.uncaughtErrorHandler})`
			);
		}
	}
};

module.exports = RequireEnsureDependency;