webpack/lib/ConstPlugin.js

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

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

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

ConstPlugin.prototype.apply = function(compiler) {
	compiler.plugin("compilation", function(compilation) {
		compilation.dependencyFactories.set(ConstDependency, new NullFactory());
		compilation.dependencyTemplates.set(ConstDependency, new ConstDependency.Template());
	});
	compiler.parser.plugin("statement if", function(statement) {
		var param = this.evaluateExpression(statement.test);
		var bool = param.asBool();
		if(typeof bool === "boolean") {
			if(statement.test.type !== "Literal") {
				var dep = new ConstDependency(bool + "", param.range);
				dep.loc = statement.loc;
				this.state.current.addDependency(dep);
			}
			return bool;
		}
	});
	compiler.parser.plugin("expression ?:", function(expression) {
		var param = this.evaluateExpression(expression.test);
		var bool = param.asBool();
		if(typeof bool === "boolean") {
			if(expression.test.type !== "Literal") {
				var dep = new ConstDependency(" " + bool + "", param.range);
				dep.loc = expression.loc;
				this.state.current.addDependency(dep);
			}
			return bool;
		}
	});
	compiler.parser.plugin("evaluate Identifier __resourceQuery", function(expr) {
		if(!this.state.module) return;
		var res = new BasicEvaluatedExpression();
		res.setString(this.state.module.splitQuery(this.state.module.resource)[1]);
		res.setRange(expr.range);
		return res;
	});
	compiler.parser.plugin("expression __resourceQuery", function() {
		if(!this.state.module) return;
		this.state.current.addVariable("__resourceQuery", JSON.stringify(this.state.module.splitQuery(this.state.module.resource)[1]));
		return true;
	});
};