Fix import statement with "subpackages" in converted ESModule

src/change_import_style.ts

@@ -19,8 +19,8 @@ function main() {
   const umdContents = convertToUmd(args, initialContents);
   fs.writeFileSync(args.output_umd_path, umdContents, 'utf8');
 
-  const commonJsContents = convertToESM(args, initialContents);
-  fs.writeFileSync(args.output_es6_path, commonJsContents, 'utf8');
+  const esmContents = convertToESM(args, initialContents);
+  fs.writeFileSync(args.output_es6_path, esmContents, 'utf8');
 }
 
 function replaceRecursiveFilePaths(args: any) {
@@ -88,7 +88,13 @@ function convertToESM(args: any, initialContents: string): string {
   };
 
   const replaceRequiresWithSubpackageImports = (contents: string) => {
-    return contents.replace(/var ([\w\d_]+) = require\((['"][\w\d@/_-]+['"])\)\.([\w\d_]+);/g, 'import * as $1 from $2;')
+    // Example:
+    //   Changes: var foo = require("@improbable-eng/grpc-web").bar;
+    //   To:      import {bar as foo} from "@improbable-eng/grpc-web";
+    return contents.replace(/var ([\w\d_]+) = require\((['"][\w\d@/_-]+['"])\)\.([\w\d_]+);/g,
+     (_, varName, moduleIdentifier, propertyName) =>
+      propertyName == varName ? `import { ${varName} } from ${moduleIdentifier}`
+        : `import { ${propertyName} as ${varName} } from ${moduleIdentifier};`);
   }
 
   const replaceCJSExportsWithECMAExports = (contents: string) => {

test/pizza_service_proto_test.spec.ts

@@ -1,6 +1,6 @@
 import {Pizza, PizzaSize} from 'rules_typescript_proto/test/proto/common/pizza_pb';
 import {OrderPizzaRequest, OrderPizzaResponse} from 'rules_typescript_proto/test/proto/pizza_service_pb';
-import {PizzaService} from 'rules_typescript_proto/test/proto/pizza_service_pb_service';
+import {PizzaService,PizzaServiceClient} from 'rules_typescript_proto/test/proto/pizza_service_pb_service';
 
 declare function require(module: string): any;
 
@@ -14,6 +14,12 @@ describe('DeliveryPerson', () => {
     expect(PizzaService).toBeDefined();
   });
 
+  it('PizzaServiceClient.orderPizza should return a UnaryResponse', () => {
+    const client = new PizzaServiceClient('http://localhost', {});
+    const response = client.orderPizza(new OrderPizzaRequest(), (_) => {});
+    expect(typeof response.cancel).toBe('function');
+  });
+
   it('Generated code seems to work', () => {
     const request = new OrderPizzaRequest();
 

test/require.config.js

@@ -2,6 +2,7 @@ require.config({
   paths: {
     '@improbable-eng/grpc-web':
         'base/npm/node_modules/@improbable-eng/grpc-web/dist/grpc-web-client.umd',
-    'browser-headers': 'base/npm/node_modules/browser-headers/dist/browser-headers.umd'
+    'browser-headers': 'base/npm/node_modules/browser-headers/dist/browser-headers.umd',
+    'test_es6_bundling': 'base/rules_typescript_proto/test/test_es6_bundling/index',
   }
 });

test/rollup.config.js

@@ -7,7 +7,7 @@ module.exports = {
     commonjs({
       // Temporary fix until https://github.com/improbable-eng/grpc-web/issues/369 is resolved.
       namedExports: {
-        './node_modules/@improbable-eng/grpc-web/dist/grpc-web-client.js': [
+        '@improbable-eng/grpc-web': [
           'grpc',
         ],
       }

test/rollup_test.spec.ts

@@ -0,0 +1,49 @@
+declare function require(module: string): any;
+
+const bundle = require('rules_typescript_proto/test/test_es6_bundling');
+
+describe('Rollup', () => {
+  it('should define Pizza with protobuf API', () => {
+    expect(bundle.Pizza).toBeDefined();
+
+    const pizza = new bundle.Pizza();
+    pizza.setSize(bundle.PizzaSize.PIZZA_SIZE_LARGE);
+
+    expect(pizza.getSize()).toBe(bundle.PizzaSize.PIZZA_SIZE_LARGE);
+    expect(Array.isArray(pizza.getToppingIdsList())).toBe(true);
+  });
+
+  it('should define DeliveryPerson', () => {
+    expect(bundle.DeliveryPerson).toBeDefined();
+    expect(new bundle.DeliveryPerson()).toBeTruthy();
+  });
+
+  it('should define PizzaService', () => {
+    expect(bundle.PizzaService).toBeDefined();
+    expect(bundle.PizzaService.serviceName).toBe('test.bazel.proto.PizzaService');
+    expect(bundle.PizzaService.OrderPizza.methodName).toBe('OrderPizza');
+  });
+
+  it('should define PizzaServiceClient', () => {
+    expect(bundle.PizzaServiceClient).toBeDefined();
+    const client = new bundle.PizzaServiceClient('http://localhost', {});
+    expect(typeof client.orderPizza).toBe('function');
+  });
+
+  it('should follow expected naming styles', () => {
+    expect(new bundle.alllowercase().setTest(1)).toBeTruthy();
+    expect(new bundle.ALLUPPERCASE().setTest(1)).toBeTruthy();
+    expect(new bundle.lowerCamelCase().setTest(1)).toBeTruthy();
+    expect(new bundle.UpperCamelCase().setTest(1)).toBeTruthy();
+    expect(new bundle.snake_case_snake_case().setTest(1)).toBeTruthy();
+    expect(new bundle.Upper_snake_Case().setTest(1)).toBeTruthy();
+    expect(new bundle.M2M().setTest(1)).toBeTruthy();
+    expect(new bundle.M_2M().setTest(1)).toBeTruthy();
+    expect(new bundle.M2_M().setTest(1)).toBeTruthy();
+    expect(new bundle.M2M_().setTest(1)).toBeTruthy();
+    expect(new bundle.m_22M().setTest(1)).toBeTruthy();
+    expect(new bundle.m42_M().setTest(1)).toBeTruthy();
+    expect(new bundle.m24M_().setTest(1)).toBeTruthy();
+    expect(new bundle.M9().setTest(1)).toBeTruthy();
+  });
+});

test/test_bundling.ts

@@ -1,4 +1,5 @@
-export {alllowercase, ALLUPPERCASE, lowerCamelCase, m24M_, M2_M, M2M, M2M_, m42_M, M9, m_22M, M_2M, snake_case_snake_case, Upper_snake_Case, UpperCamelCase,} from 'rules_typescript_proto/test/proto/naming_styles_pb';
+export { alllowercase, ALLUPPERCASE, lowerCamelCase, m24M_, M2_M, M2M, M2M_, m42_M, M9, m_22M, M_2M, snake_case_snake_case, Upper_snake_Case, UpperCamelCase, } from 'rules_typescript_proto/test/proto/naming_styles_pb';
 export { DeliveryPerson } from 'rules_typescript_proto/test/proto/common/delivery_person_pb';
 export { Pizza, PizzaSize } from 'rules_typescript_proto/test/proto/common/pizza_pb';
 export { PizzaService, PizzaServiceClient } from 'rules_typescript_proto/test/proto/pizza_service_pb_service';
+export { OrderPizzaRequest } from 'rules_typescript_proto/test/proto/pizza_service_pb';