fix(build): support transpile to commonjs

tools/transpiler/index.js

@@ -87,6 +87,7 @@ function reloadCompiler() {
   convertTypesToExpressionsInEs6Patch();
   removeNonStaticFieldDeclarationsInEs6Patch();
   disableGetterSetterAssertionPatch();
+  patchCommonJSModuleTransformerToSupportExportStar();
 }
 
 function loadModule(filepath, transpile) {
@@ -221,3 +222,29 @@ function useRttsAssertModuleForConvertingTypesToExpressions() {
     // NYI
   }
 }
+
+// TODO(tbosch): patch exports for CommonJS to support `export * from ...`
+// see https://github.com/google/traceur-compiler/issues/1042
+function patchCommonJSModuleTransformerToSupportExportStar() {
+  var traceurVersion = System.map['traceur'];
+  var CommonJsModuleTransformer = System.get(traceurVersion+'/src/codegeneration/CommonJsModuleTransformer').CommonJsModuleTransformer;
+  var parseStatement = System.get(traceurVersion+'/src/codegeneration/PlaceholderParser.js').parseStatement;
+  var prependStatements = System.get(traceurVersion+"/src/codegeneration/PrependStatements.js").prependStatements;
+
+  var _wrapModule = CommonJsModuleTransformer.prototype.wrapModule;
+  CommonJsModuleTransformer.prototype.wrapModule = function(statements) {
+    if (this.hasStarExports()) {
+      var last = statements[statements.length - 1];
+      statements = statements.slice(0, -1);
+      var exportObject = last.expression;
+      if (exportObject.propertyNameAndValues) {
+        throw new Error('Don\'t support export * with named exports right now...');
+      }
+      statements.push(parseStatement(['module.exports = ', ';'], exportObject));
+      return statements;
+    } else {
+      return _wrapModule.apply(this, arguments);
+    }
+  }
+}
+

tools/transpiler/unittest/transpilertests.js

@@ -1,4 +1,8 @@
 var compiler = require('../index');
+var temp = require('temp');
+var fs = require('fs');
+
+temp.track();
 
 var DEFAULT_OPTIONS = {
   sourceMaps: false,
@@ -157,6 +161,34 @@ describe('transpile to es6', function() {
 
 });
 
+describe('transpile to cjs', function() {
+  var options;
+
+  beforeEach(function() {
+    options = merge(DEFAULT_OPTIONS, {modules: 'commonjs'});
+  });
+
+  function compileAndWrite(input) {
+    var transpiledCode = compiler.compile(options, "test.js", input).js;
+    var tempFile = temp.openSync('ng2transpiler');
+    fs.writeSync(tempFile.fd, transpiledCode);
+    return tempFile.path;
+  }
+
+  it('should transpile export *', function() {
+    var file1 = compileAndWrite('export var a = 1');
+    var file2 = compileAndWrite('export * from "' + file1 + '"');
+    expect(require(file2).a).toBe(1);
+  });
+
+  it('should transpile export {name}', function() {
+    var file1 = compileAndWrite('export var a = 1');
+    var file2 = compileAndWrite('export {a} from "' + file1 + '"');
+    expect(require(file2).a).toBe(1);
+  });
+
+});
+
 
 function merge(a, b) {
   var result = {};