webpack/lib/CompatibilityPlugin.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, jade, coffee, css, less, ... and your custom stuff.

/*
	MIT License http://www.opensource.org/licenses/mit-license.php
	Author Tobias Koppers @sokra
*/
var path = require("path");
var ConstDependency = require("./dependencies/ConstDependency");

var ModuleAliasPlugin = require("enhanced-resolve/lib/ModuleAliasPlugin");

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

function CompatibilityPlugin() {
}
module.exports = CompatibilityPlugin;

CompatibilityPlugin.prototype.apply = function(compiler) {
	compiler.plugin("compilation", function(compilation, params) {
		compilation.dependencyFactories.set(ConstDependency, new NullFactory());
		compilation.dependencyTemplates.set(ConstDependency, new ConstDependency.Template());
	});
	compiler.resolvers.normal.apply(
		new ModuleAliasPlugin({
			"enhanced-require": path.join(__dirname, "..", "buildin", "return-require.js")
		})
	);
	compiler.parser.plugin("call require", function(expr) {
		// support for browserify style require delegator: "require(o, !0)"
		if(expr.arguments.length !== 2) return;
		var second = this.evaluateExpression(expr.arguments[1]);
		if(!second.isBoolean()) return;
		if(second.asBool() !== true) return;
		var dep = new ConstDependency("require", expr.callee.range);
		dep.loc = expr.loc;
		if(this.state.current.dependencies.length > 1) {
			var last = this.state.current.dependencies[this.state.current.dependencies.length - 1];
			if(last.critical && last.request === "." && last.userRequest === "." && last.recursive)
				this.state.current.dependencies.pop();
		}
		dep.critical = "This seem to be a pre-built javascript file. Even while this is possible, it's not recommended. Try to require to orginal source to get better results.";
		this.state.current.addDependency(dep);
		return true;
	});
};