[INTERNAL] Remove object-assign polyfill

Supported in Node.js v4+

Author: matz3

lib/index.js

@@ -1,7 +1,6 @@
 "use strict";
 
 const path = require("path");
-const assign = require("object-assign");
 const clone = require("clone");
 const css = require("css");
 
@@ -120,7 +119,7 @@ Builder.prototype.build = function(options) {
 	const mFileMappings = {};
 
 	// Assign default options
-	options = assign({
+	options = Object.assign({
 		lessInput: null,
 		lessInputPath: null,
 		rtl: true,
@@ -225,7 +224,7 @@ Builder.prototype.build = function(options) {
 			const oVariableCollector = new VariableCollectorPlugin(options.compiler);
 
 			// render to css
-			result.css = tree.toCSS(assign({}, options.compiler, {
+			result.css = tree.toCSS(Object.assign({}, options.compiler, {
 				plugins: [oImportCollector, oVariableCollector]
 			}));
 
@@ -246,7 +245,7 @@ Builder.prototype.build = function(options) {
 			}
 
 			if (oRTL) {
-				result.cssRtl = tree.toCSS(assign({}, options.compiler, {
+				result.cssRtl = tree.toCSS(Object.assign({}, options.compiler, {
 					plugins: [oRTL]
 				}));
 			}
@@ -270,13 +269,13 @@ Builder.prototype.build = function(options) {
 					// generate the skeleton-css and the less-variables
 					const CSSVariablesCollectorPlugin = require("./plugin/css-variables-collector");
 					const oCSSVariablesCollector = new CSSVariablesCollectorPlugin(config);
-					result.cssSkeleton = tree.toCSS(assign({}, options.compiler, {
+					result.cssSkeleton = tree.toCSS(Object.assign({}, options.compiler, {
 						plugins: [oCSSVariablesCollector]
 					}));
 					result.cssVariablesSource = oCSSVariablesCollector.toLessVariables();
 					if (oRTL) {
 						const oCSSVariablesCollectorRTL = new CSSVariablesCollectorPlugin(config);
-						result.cssSkeletonRtl = tree.toCSS(assign({}, options.compiler, {
+						result.cssSkeletonRtl = tree.toCSS(Object.assign({}, options.compiler, {
 							plugins: [oCSSVariablesCollectorRTL, oRTL]
 						}));
 					}
@@ -289,7 +288,7 @@ Builder.prototype.build = function(options) {
 								reject(err);
 							} else {
 								const CSSVariablesPointerPlugin = require("./plugin/css-variables-pointer");
-								result.cssVariables = tree.toCSS(assign({}, options.compiler, {
+								result.cssVariables = tree.toCSS(Object.assign({}, options.compiler, {
 									plugins: [new CSSVariablesPointerPlugin()]
 								}));
 								resolve(result);