evaluate null

fixes #633

lib/BasicEvaluatedExpression.js

@@ -7,6 +7,9 @@ function BasicEvaluatedExpression() {
 }
 module.exports = BasicEvaluatedExpression;
 
+BasicEvaluatedExpression.prototype.isNull = function() {
+	return !!this.null;
+};
 BasicEvaluatedExpression.prototype.isString = function() {
 	return Object.prototype.hasOwnProperty.call(this, "string");
 };
@@ -36,6 +39,7 @@ BasicEvaluatedExpression.prototype.isWrapped = function() {
 };
 BasicEvaluatedExpression.prototype.asBool = function() {
 	if(this.isBoolean()) return this.bool;
+	else if(this.isNull()) return false;
 	else if(this.isString()) return !!this.string;
 	else if(this.isNumber()) return !!this.number;
 	else if(this.isRegExp()) return true;
@@ -48,6 +52,7 @@ BasicEvaluatedExpression.prototype.set = function(value) {
 	if(typeof value === "string") return this.setString(value);
 	if(typeof value === "number") return this.setNumber(value);
 	if(typeof value === "boolean") return this.setBoolean(value);
+	if(value === null) return this.setNull();
 	if(value instanceof RegExp) return this.setRegExp(value);
 	if(Array.isArray(value)) return this.setArray(value);
 	return this;
@@ -59,6 +64,10 @@ BasicEvaluatedExpression.prototype.setString = function(str) {
 		this.string = str;
 	return this;
 };
+BasicEvaluatedExpression.prototype.setNull = function(str) {
+	this.null = true;
+	return this;
+};
 BasicEvaluatedExpression.prototype.setNumber = function(num) {
 	if(num === null)
 		delete this.number;

lib/Parser.js

@@ -33,6 +33,8 @@ Parser.prototype.initializeEvaluating = function() {
 		case "boolean":
 			return new BasicEvaluatedExpression().setBoolean(expr.value).setRange(expr.range);
 		}
+		if(expr.value === null)
+			return new BasicEvaluatedExpression().setNull().setRange(expr.range);
 		if(expr.value instanceof RegExp)
 			return new BasicEvaluatedExpression().setRegExp(expr.value).setRange(expr.range);
 	});

test/cases/parsing/evaluate/index.js

@@ -5,6 +5,12 @@ it("should define DEBUG", function() {
 	var y = DEBUG ? require("fail") : require("./a");
 });
 
+it("should evaluate null", function() {
+	var y = null ? require("fail") : require("./a");
+	if(null)
+		require("fail");
+});
+
 it("should short-circut evaluating", function() {
 	var expr;
 	var a = DEBUG && expr ? require("fail") : require("./a");