fix enum export by upgrading closure compiler

If you wrote "export enum ...", the generated ES6 JavaScript would
fail to compile in the Closure compiler.  I tracked this down to
a bug that was fixed in the upstream Closure compiler, so to fix
this I had to make us use a newer version of the upstream compiler.

To use a newer version of the upstream compiler, I removed one of
our indirection layers: we previously used the 'closure-compiler'
npm library which pulled in 'google-closure-compiler', but now the
latter module exposes a simple API so it's easy enough to just use
it directly.

Fixes issue #50.

Author: evmar

package.json

@@ -14,7 +14,7 @@
   "devDependencies": {
     "chai": "^2.1.1",
     "clang-format": "1.0.33",
-    "closure-compiler": "^0.2.12",
+    "google-closure-compiler": "^20151216.2.0",
     "gulp": "^3.8.11",
     "gulp-clang-format": "^1.0.22",
     "gulp-mocha": "^2.0.0",

test/closure-compiler.d.ts

@@ -2,7 +2,7 @@ import * as fs from 'fs';
 import * as path from 'path';
 import * as ts from 'typescript';
 import {expect} from 'chai';
-import {CompileOptions, compile} from 'closure-compiler';
+import * as closure from 'google-closure-compiler';
 
 import {goldenTests} from './test_support';
 
@@ -11,15 +11,20 @@ export function checkClosureCompile(jsFiles: string[], done: (err: Error) => voi
   var total = jsFiles.length;
   if (!total) throw new Error('No JS files in ' + JSON.stringify(jsFiles));
 
-  var CLOSURE_COMPILER_OPTS: CompileOptions = {
+  var CLOSURE_COMPILER_OPTS: closure.CompileOptions = {
     'checks-only': true,
     'jscomp_error': 'checkTypes',
     'js': jsFiles,
-    'language_in': 'ECMASCRIPT6_STRICT'
+    'language_in': 'ECMASCRIPT6_STRICT',
   };
 
-  compile(null, CLOSURE_COMPILER_OPTS, (err, stdout, stderr) => {
+  var compiler = new closure.compiler(CLOSURE_COMPILER_OPTS);
+  compiler.run((exitCode, stdout, stderr) => {
     console.log('Closure compilation:', total, 'done after', Date.now() - startTime, 'ms');
+    let err: Error = null;
+    if (exitCode != 0) {
+      err = new Error(stderr);
+    }
     done(err);
   });
 }

test/e2e_test.ts

@@ -0,0 +1,7 @@
+declare module 'google-closure-compiler' {
+  type CompileOptions = {[key: string]: string[] | string | boolean};
+  interface Compiler {
+    run(callback: (exitCode: number, stdout: string, stderr: string) => void): void;
+  }
+  export var compiler: { new (opts: CompileOptions): Compiler; }
+}

test/google-closure-compiler.d.ts

@@ -1 +1,4 @@
-enum FooEnum {XYZ, PI = 3.14159}
+enum EnumTest1 {XYZ, PI = 3.14159}
+
+// This additional exported enum is here to exercise the fix for issue #51.
+export enum EnumTest2 {XYZ, PI = 3.14159}

test_files/enum.ts

@@ -1,10 +1,21 @@
 /** @typedef {number} */
-var FooEnum;
-(function (FooEnum) {
-    FooEnum[FooEnum["XYZ"] = 0] = "XYZ";
-    FooEnum[FooEnum["PI"] = 3.14159] = "PI";
-})(FooEnum || (FooEnum = {}));
-/** @type {FooEnum} */
-FooEnum.XYZ = 0;
-/** @type {FooEnum} */
-FooEnum.PI = 3.14159;
+var EnumTest1;
+(function (EnumTest1) {
+    EnumTest1[EnumTest1["XYZ"] = 0] = "XYZ";
+    EnumTest1[EnumTest1["PI"] = 3.14159] = "PI";
+})(EnumTest1 || (EnumTest1 = {}));
+/** @type {EnumTest1} */
+EnumTest1.XYZ = 0;
+/** @type {EnumTest1} */
+EnumTest1.PI = 3.14159;
+/** @typedef {number} */
+// This additional exported enum is here to exercise the fix for issue #51.
+export var EnumTest2;
+(function (EnumTest2) {
+    EnumTest2[EnumTest2["XYZ"] = 0] = "XYZ";
+    EnumTest2[EnumTest2["PI"] = 3.14159] = "PI";
+})(EnumTest2 || (EnumTest2 = {}));
+/** @type {EnumTest2} */
+EnumTest2.XYZ = 0;
+/** @type {EnumTest2} */
+EnumTest2.PI = 3.14159;

test_files/es6/enum.js

@@ -1,6 +1,16 @@
 /** @typedef {number} */
-enum FooEnum {XYZ, PI = 3.14159}
-/** @type {FooEnum} */
-(<any>FooEnum).XYZ = 0;
-/** @type {FooEnum} */
-(<any>FooEnum).PI =  3.14159;
+enum EnumTest1 {XYZ, PI = 3.14159}
+/** @type {EnumTest1} */
+(<any>EnumTest1).XYZ = 0;
+/** @type {EnumTest1} */
+(<any>EnumTest1).PI =  3.14159;
+/** @typedef {number} */
+
+
+// This additional exported enum is here to exercise the fix for issue #51.
+export enum EnumTest2 {XYZ, PI = 3.14159}
+/** @type {EnumTest2} */
+(<any>EnumTest2).XYZ = 0;
+/** @type {EnumTest2} */
+(<any>EnumTest2).PI =  3.14159;
+

test_files/sickle/enum.ts

@@ -7,7 +7,7 @@
   "files": [
     "src/sickle.ts",
     "test/sickle_test.ts",
-    "test/closure-compiler.d.ts",
+    "test/google-closure-compiler.d.ts",
     "typings/tsd.d.ts"
   ]
 }