export platform specific objects through proxy

detox/src/Detox.js

@@ -43,7 +43,7 @@ class Detox {
   async init(userParams) {
     const sessionConfig = await this._getSessionConfig();
     const defaultParams = {launchApp: true, initGlobals: true};
-    const params = Object.assign(userParams, defaultParams);
+    const params = Object.assign(defaultParams, userParams || {});
 
     if (!this.userSession) {
       this.server = new DetoxServer(new URL(sessionConfig.server).port);

detox/src/exportWrapper.test.js

@@ -1,28 +1,56 @@
-const iosExports = require('./ios/expect');
-const androidExports = require('./android/expect');
 const exportWrapper = require('./exportWrapper');
 const platform = require('./platform');
+jest.mock('./ios/expect');
+jest.mock('./android/expect');
+const iosExports = require('./ios/expect');
+const androidExports = require('./android/expect');
 
 describe('exportWrapper', () => {
-  const mockDevice = {};
+  const mockDevice = {method: jest.fn()};
+
+  it(`proxies ios specific objects`, async () => {
+    const arg1 = 1;
+    const arg2 = 'test';
 
-  it(`exports ios specific objects`, async () => {
     platform.set('ios.none', mockDevice);
+    iosExports.by.method = jest.fn();
+
+    exportWrapper.device.method(arg1, arg2);
+    expect(mockDevice.method).toHaveBeenCalledWith(arg1, arg2);
+
+    exportWrapper.expect(arg1, arg2);
+    expect(iosExports.expect).toHaveBeenCalledWith(arg1, arg2);
 
-    expect(exportWrapper.device).toBe(mockDevice);
-    expect(exportWrapper.expect).toBe(iosExports.expect);
-    expect(exportWrapper.element).toBe(iosExports.element);
-    expect(exportWrapper.waitFor).toBe(iosExports.waitFor);
-    expect(exportWrapper.by).toBe(iosExports.by);
+    exportWrapper.element(arg1, arg2);
+    expect(iosExports.element).toHaveBeenCalledWith(arg1, arg2);
+
+    exportWrapper.waitFor(arg1, arg2);
+    expect(iosExports.waitFor).toHaveBeenCalledWith(arg1, arg2);
+
+    exportWrapper.by.method(arg1, arg2);
+    expect(iosExports.by.method).toHaveBeenCalledWith(arg1, arg2);
   });
 
-  it(`exports android specific objects`, async () => {
+  it(`proxies android specific objects`, async () => {
+    const arg1 = 1;
+    const arg2 = 'test';
+
     platform.set('android.attached', mockDevice);
+    androidExports.by.method = jest.fn();
+
+    exportWrapper.device.method(arg1, arg2);
+    expect(mockDevice.method).toHaveBeenCalledWith(arg1, arg2);
+
+    exportWrapper.expect(arg1, arg2);
+    expect(androidExports.expect).toHaveBeenCalledWith(arg1, arg2);
+
+    exportWrapper.element(arg1, arg2);
+    expect(androidExports.element).toHaveBeenCalledWith(arg1, arg2);
+
+    exportWrapper.waitFor(arg1, arg2);
+    expect(androidExports.waitFor).toHaveBeenCalledWith(arg1, arg2);
 
-    expect(exportWrapper.device).toBe(mockDevice);
-    expect(exportWrapper.expect).toBe(androidExports.expect);
-    expect(exportWrapper.element).toBe(androidExports.element);
-    expect(exportWrapper.waitFor).toBe(androidExports.waitFor);
-    expect(exportWrapper.by).toBe(androidExports.by);
+    exportWrapper.by.method(arg1, arg2);
+    expect(androidExports.by.method).toHaveBeenCalledWith(arg1, arg2);
   });
 });