webpack/lib/dependencies/RequireEnsurePlugin.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 RequireEnsureItemDependency = require("./RequireEnsureItemDependency");
const RequireEnsureDependency = require("./RequireEnsureDependency");

const NullFactory = require("../NullFactory");

const RequireEnsureDependenciesBlockParserPlugin = require("./RequireEnsureDependenciesBlockParserPlugin");

const ParserHelpers = require("../ParserHelpers");

class RequireEnsurePlugin {
	apply(compiler) {
		compiler.hooks.compilation.tap(
			"RequireEnsurePlugin",
			(compilation, { normalModuleFactory }) => {
				compilation.dependencyFactories.set(
					RequireEnsureItemDependency,
					normalModuleFactory
				);
				compilation.dependencyTemplates.set(
					RequireEnsureItemDependency,
					new RequireEnsureItemDependency.Template()
				);

				compilation.dependencyFactories.set(
					RequireEnsureDependency,
					new NullFactory()
				);
				compilation.dependencyTemplates.set(
					RequireEnsureDependency,
					new RequireEnsureDependency.Template()
				);

				const handler = (parser, parserOptions) => {
					if (
						parserOptions.requireEnsure !== undefined &&
						!parserOptions.requireEnsure
					)
						return;

					new RequireEnsureDependenciesBlockParserPlugin().apply(parser);
					parser.hooks.evaluateTypeof
						.for("require.ensure")
						.tap(
							"RequireEnsurePlugin",
							ParserHelpers.evaluateToString("function")
						);
					parser.hooks.typeof
						.for("require.ensure")
						.tap(
							"RequireEnsurePlugin",
							ParserHelpers.toConstantDependency(
								parser,
								JSON.stringify("function")
							)
						);
				};

				normalModuleFactory.hooks.parser
					.for("javascript/auto")
					.tap("RequireEnsurePlugin", handler);
				normalModuleFactory.hooks.parser
					.for("javascript/dynamic")
					.tap("RequireEnsurePlugin", handler);
			}
		);
	}
}
module.exports = RequireEnsurePlugin;