Updates UglifyJs to 2.8.x to accept additional compress options

Bumps the minimum version of UglifyJs and substitutes `.compress()` for
`.transform()` as recommended. In addition to a new test covering
`compress` options this commit also contains updates to make existing
tests pass with the update.

input.js

@@ -0,0 +1 @@
+invalid javascript

lib/optimize/UglifyJsPlugin.js

@@ -87,7 +87,7 @@ class UglifyJsPlugin {
 							const compress = uglify.Compressor(options.compress || {
 								warnings: false
 							}); // eslint-disable-line new-cap
-							ast = ast.transform(compress);
+							ast = compress.compress(ast);
 						}
 						if(options.mangle !== false) {
 							ast.figure_out_scope(options.mangle || {});

package.json

@@ -20,7 +20,7 @@
     "source-map": "^0.5.3",
     "supports-color": "^3.1.0",
     "tapable": "~0.2.5",
-    "uglify-js": "^2.7.5",
+    "uglify-js": "^2.8.5",
     "watchpack": "^1.2.0",
     "webpack-sources": "^0.1.4",
     "yargs": "^6.0.0"

test/UglifyJsPlugin.test.js

@@ -122,7 +122,7 @@ describe("UglifyJsPlugin", function() {
 						}], function() {
 							compilation.errors.length.should.be.exactly(1);
 							compilation.errors[0].should.be.an.Error;
-							compilation.errors[0].message.should.have.containEql("SyntaxError");
+							compilation.errors[0].message.should.have.containEql("Unexpected token");
 							compilation.errors[0].message.should.have.containEql("[test2.js:1,8]");
 						});
 					});

test/configCases/plugins/uglifyjs-plugin/compress.js

@@ -0,0 +1,14 @@
+function f() {
+	var a = 1, b = 2, c = 3;
+	if (a) {
+		b = c;
+	} else {
+		c = b;
+	}
+	console.log(a + b);
+	console.log(b + c);
+	console.log(a + c);
+	console.log(a + b + c);
+}
+
+module.exports = f;

test/configCases/plugins/uglifyjs-plugin/index.js

@@ -44,4 +44,11 @@ it("should remove extracted comments and insert a banner", function() {
 	source.should.containEql("/*! For license information please see extract.js.LICENSE */");
 });
 
+it("should pass compress options", function() {
+	var fs = require("fs"),
+		path = require("path");
+	var source = fs.readFileSync(path.join(__dirname, "compress.js"), "utf-8");
+	source.should.containEql("function e(){var n=2;n=3,console.log(1+n),console.log(n+3),console.log(4),console.log(1+n+3)}");
+});
+
 require.include("./test.js");

test/configCases/plugins/uglifyjs-plugin/webpack.config.js

@@ -8,7 +8,8 @@ module.exports = {
 		bundle0: ["./index.js"],
 		vendors: ["./vendors.js"],
 		ie8: ["./ie8.js"],
-		extract: ["./extract.js"]
+		extract: ["./extract.js"],
+		compress: ["./compress.js"]
 	},
 	output: {
 		filename: "[name].js"
@@ -28,5 +29,15 @@ module.exports = {
 				screw_ie8: false
 			}
 		}),
+		new webpack.optimize.UglifyJsPlugin({
+			include: ["compress.js"],
+			compress: {
+				conditionals: true,
+				evaluate: true,
+				passes: 2,
+				reduce_vars: true,
+				unused: true
+			}
+		}),
 	]
 };

test/statsCases/warnings-uglifyjs/expected.txt

@@ -1,7 +1,7 @@
 Hash: 4beee256fa6b8f69eae8
 Time: Xms
-    Asset    Size  Chunks             Chunk Names
-bundle.js  2.3 kB       0  [emitted]  main
+    Asset     Size  Chunks             Chunk Names
+bundle.js  2.24 kB       0  [emitted]  main
 chunk    {0} bundle.js (main) 1.04 kB [entry] [rendered]
    [0] (webpack)/buildin/module.js 495 bytes {0} [built]
    [1] (webpack)/test/statsCases/warnings-uglifyjs/a.js 249 bytes {0} [built]