added SourceMap support

Author: sokra

index.js

@@ -3,6 +3,8 @@
 	Author Tobias Koppers @sokra
 */
 var csso = require("csso");
+var SourceNode = require("source-map").SourceNode;
+var loaderUtils = require("loader-utils");
 module.exports = function(content) {
 	this.cacheable && this.cacheable();
 	var result = [];
@@ -33,7 +35,15 @@ module.exports = function(content) {
 		return "\"+require(" + JSON.stringify(urlToRequire(url)) + ")+\"";
 	});
 	result.push(css);
-	return "module.exports =\n\t" + result.join(" +\n\t") + ";";
+	var cssRequest = loaderUtils.getRemainingRequest(this);
+	var node = new SourceNode(1, 0,
+		cssRequest,
+		"module.exports =\n\t" + result.join(" +\n\t") + ";");
+	var stringWithMap = node.toStringWithSourceMap({
+		file: loaderUtils.getCurrentRequest(this)
+	});
+	stringWithMap.map.setSourceContent(cssRequest, content);
+	this.callback(null, stringWithMap.code, stringWithMap.map.toJSON());
 }
 
 function urlToRequire(url) {

package.json

@@ -1,10 +1,12 @@
 {
 	"name": "css-loader",
-	"version": "0.5.2",
+	"version": "0.6.0",
 	"author": "Tobias Koppers @sokra",
 	"description": "css loader module for webpack",
 	"dependencies": {
-		"csso": "1.3.x"
+		"csso": "1.3.x",
+		"source-map": "0.1.x",
+		"loader-utils": "0.2.x"
 	},
 	"devDependencies": {
 		"mocha": "1.8.x",