Basic support for Jest runner (wix#335)

Add basic Jest runner support in Detox core and detox-cli

Author: Kureev

detox/local-cli/detox-test.js

@@ -4,7 +4,7 @@ const program = require('commander');
 const path = require('path');
 const cp = require('child_process');
 program
-  .option('-r, --runner [runner]', 'Test runner (currently supports mocha)', 'mocha')
+  .option('-r, --runner [runner]', 'Test runner (currently supports mocha)')
   .option('-o, --runner-config [config]', 'Test runner config file', 'mocha.opts')
   .option('-l, --loglevel [value]', 'info, debug, verbose, silly, wss')
   .option('-c, --configuration [device configuration]', 'Select a device configuration from your defined configurations,'
@@ -21,26 +21,54 @@ program
 const config = require(path.join(process.cwd(), 'package.json')).detox;
 const testFolder = config.specs || 'e2e';
 
-const loglevel = program.loglevel ? `--loglevel ${program.loglevel}` : '';
-const configuration = program.configuration ? `--configuration ${program.configuration}` : '';
-const cleanup = program.cleanup ? `--cleanup` : '';
-const reuse = program.reuse ? `--reuse` : '';
-const artifactsLocation = program.artifactsLocation ? `--artifacts-location ${program.artifactsLocation}` : '';
+let runner = config.runner || 'mocha';
+
+if (program.runner) {
+  runner = program.runner;
+}
+
+function runMocha() {
+  const loglevel = program.loglevel ? `--loglevel ${program.loglevel}` : '';
+  const configuration = program.configuration ? `--configuration ${program.configuration}` : '';
+  const cleanup = program.cleanup ? `--cleanup` : '';
+  const reuse = program.reuse ? `--reuse` : '';
+  const artifactsLocation = program.artifactsLocation ? `--artifacts-location ${program.artifactsLocation}` : '';
+
+  const debugSynchronization = program.debugSynchronization ? `--debug-synchronization ${program.debugSynchronization}` : '';
+  const command = `node_modules/.bin/mocha ${testFolder} --opts ${testFolder}/${program.runnerConfig} ${configuration} ${loglevel} ${cleanup} ${reuse} ${debugSynchronization} ${artifactsLocation}`;
+
+  console.log(command);
+  cp.execSync(command, {stdio: 'inherit'});
+}
+
+function runJest() {
+  const command = `node_modules/.bin/jest ${testFolder} --runInBand`;
+  console.log(command);
+  cp.execSync(command, {
+    stdio: 'inherit',
+    env: {
+      ...process.env,
+      configuration: program.configuration,
+      loglevel: program.loglevel,
+      cleanup: program.cleanup,
+      reuse: program.reuse,
+      debugSynchronization: program.debugSynchronization,
+      artifactsLocation: program.artifactsLocation
+    }
+  });
+}
 
 if (typeof program.debugSynchronization === "boolean") {
   program.debugSynchronization = 3000;
 }
-let debugSynchronization = program.debugSynchronization ? `--debug-synchronization ${program.debugSynchronization}` : '';
-
 
-let command;
-switch (program.runner) {
+switch (runner) {
   case 'mocha':
-    command = `node_modules/.bin/${program.runner} ${testFolder} --opts ${testFolder}/${program.runnerConfig} ${configuration} ${loglevel} ${cleanup} ${reuse} ${debugSynchronization} ${artifactsLocation}`;
+    runMocha();
+    break;
+  case 'jest':
+    runJest();
     break;
   default:
-    throw new Error(`${program.runner} is not supported in detox cli tools. You can still run your tests with the runner's own cli tool`);
+    throw new Error(`${runner} is not supported in detox cli tools. You can still run your tests with the runner's own cli tool`);
 }
-
-console.log(command);
-cp.execSync(command, {stdio: 'inherit'});

detox/src/Detox.js

@@ -22,7 +22,6 @@ const DEVICE_CLASSES = {
 };
 
 class Detox {
-
   constructor(userConfig) {
     if (!userConfig) {
       throw new Error(`No configuration was passed to detox, make sure you pass a config when calling 'detox.init(config)'`);
@@ -33,10 +32,10 @@ class Detox {
     this.device = null;
     this._currentTestNumber = 0;
     const artifactsLocation = argparse.getArgValue('artifacts-location');
-    if(artifactsLocation !== undefined) {
+    if (artifactsLocation !== undefined) {
       try {
         this._artifactsPathsProvider = new ArtifactsPathsProvider(artifactsLocation);
-      } catch(ex) {
+      } catch (ex) {
         log.warn(ex);
       }
     }
@@ -130,7 +129,7 @@ class Detox {
     }
 
     if (!deviceConfig) {
-      throw new Error(`Cannot determine which configuration to use. use --configuration to choose one of the following: 
+      throw new Error(`Cannot determine which configuration to use. use --configuration to choose one of the following:
                       ${Object.keys(configurations)}`);
     }
 

detox/src/Detox.test.js

@@ -4,17 +4,16 @@ describe('Detox', () => {
   let fs;
   let Detox;
   let detox;
-  let minimist;
-  let clientMockData = {lastConstructorArguments: null};
-  let deviceMockData = {lastConstructorArguments: null};
+  const clientMockData = {lastConstructorArguments: null};
+  const deviceMockData = {lastConstructorArguments: null};
 
   beforeEach(async () => {
     function setCustomMock(modulePath, dataObject) {
       const JestMock = jest.genMockFromModule(modulePath);
       class FinalMock extends JestMock {
-        constructor() {
-          super(...arguments);
-          dataObject.lastConstructorArguments = arguments;
+        constructor(...rest) {
+          super(rest);
+          dataObject.lastConstructorArguments = rest;
         }
       }
       jest.setMock(modulePath, FinalMock);
@@ -23,12 +22,12 @@ describe('Detox', () => {
     jest.mock('npmlog');
     jest.mock('fs');
     fs = require('fs');
-    jest.mock('minimist');
-    minimist = require('minimist');
     jest.mock('./ios/expect');
     setCustomMock('./client/Client', clientMockData);
     setCustomMock('./devices/Device', deviceMockData);
 
+    process.env = {};
+
     jest.mock('./devices/IosDriver');
     jest.mock('./devices/SimulatorDriver');
     jest.mock('./devices/Device');
@@ -66,7 +65,7 @@ describe('Detox', () => {
   });
 
   it(`Passing --cleanup should shutdown the currently running device`, async () => {
-    mockCommandLineArgs({cleanup: true});
+    process.env.cleanup = true;
     Detox = require('./Detox');
 
     detox = new Detox(schemes.validOneDeviceNoSession);
@@ -99,7 +98,7 @@ describe('Detox', () => {
   });
 
   it(`Two valid devices, detox should init with the device passed in '--configuration' cli option`, async () => {
-    mockCommandLineArgs({configuration: 'ios.sim.debug'});
+    process.env.configuration = 'ios.sim.debug';
     Detox = require('./Detox');
 
     detox = new Detox(schemes.validTwoDevicesNoSession);
@@ -108,7 +107,7 @@ describe('Detox', () => {
   });
 
   it(`Two valid devices, detox should throw if device passed in '--configuration' cli option doesn't exist`, async () => {
-    mockCommandLineArgs({configuration: 'nonexistent'});
+    process.env.configuration = 'nonexistent';
     Detox = require('./Detox');
 
     detox = new Detox(schemes.validTwoDevicesNoSession);
@@ -121,7 +120,7 @@ describe('Detox', () => {
   });
 
   it(`Two valid devices, detox should throw if device passed in '--configuration' cli option doesn't exist`, async () => {
-    mockCommandLineArgs({configuration: 'nonexistent'});
+    process.env.configuration = 'nonexistent';
     Detox = require('./Detox');
 
     detox = new Detox(schemes.validTwoDevicesNoSession);
@@ -165,22 +164,22 @@ describe('Detox', () => {
   });
 
   it(`Detox should use session defined per configuration - none`, async () => {
-    mockCommandLineArgs({configuration: 'ios.sim.none'});
+    process.env.configuration = 'ios.sim.none';
     Detox = require('./Detox');
     detox = new Detox(schemes.sessionPerConfiguration);
     await detox.init();
 
-    let expectedSession = schemes.sessionPerConfiguration.configurations['ios.sim.none'].session;
+    const expectedSession = schemes.sessionPerConfiguration.configurations['ios.sim.none'].session;
     expect(clientMockData.lastConstructorArguments[0]).toBe(expectedSession);
   });
 
   it(`Detox should use session defined per configuration - release`, async () => {
-    mockCommandLineArgs({configuration: 'ios.sim.release'});
+    process.env.configuration = 'ios.sim.release';
     Detox = require('./Detox');
     detox = new Detox(schemes.sessionPerConfiguration);
     await detox.init();
 
-    let expectedSession = schemes.sessionPerConfiguration.configurations['ios.sim.release'].session;
+    const expectedSession = schemes.sessionPerConfiguration.configurations['ios.sim.release'].session;
     expect(clientMockData.lastConstructorArguments[0]).toBe(expectedSession);
   });
 
@@ -189,12 +188,12 @@ describe('Detox', () => {
     detox = new Detox(schemes.sessionInCommonAndInConfiguration);
     await detox.init();
 
-    let expectedSession = schemes.sessionInCommonAndInConfiguration.configurations['ios.sim.none'].session;
+    const expectedSession = schemes.sessionInCommonAndInConfiguration.configurations['ios.sim.none'].session;
     expect(clientMockData.lastConstructorArguments[0]).toBe(expectedSession);
   });
 
   it(`beforeEach() - should set device artifacts destination`, async () => {
-    mockCommandLineArgs({'artifacts-location': '/tmp'});
+    process.env.artifactsLocation = '/tmp';
     Detox = require('./Detox');
     detox = new Detox(schemes.validOneDeviceAndSession);
     await detox.init();
@@ -211,7 +210,7 @@ describe('Detox', () => {
   });
 
   it(`afterEach() - should call device.finalizeArtifacts`, async () => {
-    mockCommandLineArgs({'artifacts-location': '/tmp'});
+    process.env.artifactsLocation = '/tmp';
     Detox = require('./Detox');
     detox = new Detox(schemes.validOneDeviceAndSession);
     await detox.init();
@@ -228,13 +227,11 @@ describe('Detox', () => {
   });
 
   it(`the constructor should catch exception from ArtifactsPathsProvider`, async () => {
-    mockCommandLineArgs({'artifacts-location': '/tmp'});
-    fs.mkdirSync = jest.fn(() => {throw 'Could not create artifacts root dir'});
+    process.env.artifactsLocation = '/tmp';
+    fs.mkdirSync = jest.fn(() => {
+      throw Error('Could not create artifacts root dir');
+    });
     Detox = require('./Detox');
     detox = new Detox(schemes.validOneDeviceAndSession);
   });
-
-  function mockCommandLineArgs(args) {
-    minimist.mockReturnValue(args);
-  }
 });

detox/src/utils/argparse.js

@@ -1,7 +1,15 @@
 const argv = require('minimist')(process.argv.slice(2));
 
 function getArgValue(key) {
-  const value = argv ? argv[key] : undefined;
+  let value;
+
+  if (argv && argv[key]) {
+    value = argv[key];
+  } else {
+    const camelCasedKey = key.replace(/(\-\w)/g, (m) => m[1].toUpperCase());
+    value = process.env[camelCasedKey];
+  }
+
   return value;
 }
 

detox/src/utils/argparse.test.js

@@ -1,20 +1,39 @@
-const _ = require('lodash');
+jest.unmock('process');
 
 describe('argparse', () => {
-  let argparse;
+  describe('using env variables', () => {
+    let argparse;
 
-  beforeEach(() => {
-    jest.mock('minimist');
-    const minimist = require('minimist');
-    minimist.mockReturnValue({test: 'a value'});
-    argparse = require('./argparse');
-  });
+    beforeEach(() => {
+      process.env.fooBar = 'a value';
+      argparse = require('./argparse');
+    });
+
+    it(`nonexistent key should return undefined result`, () => {
+      expect(argparse.getArgValue('blah')).not.toBeDefined();
+    });
 
-  it(`nonexistent key should return undefined result`, () => {
-    expect(argparse.getArgValue('blah')).not.toBeDefined();
+    it(`existing key should return a result`, () => {
+      expect(argparse.getArgValue('foo-bar')).toBe('a value');
+    });
   });
 
-  it(`existing key should return a result`, () => {
-    expect(argparse.getArgValue('test')).toBe('a value');
+  describe('using arguments', () => {
+    let argparse;
+
+    beforeEach(() => {
+      jest.mock('minimist');
+      const minimist = require('minimist');
+      minimist.mockReturnValue({'kebab-case-key': 'a value'});
+      argparse = require('./argparse');
+    });
+
+    it(`nonexistent key should return undefined result`, () => {
+      expect(argparse.getArgValue('blah')).not.toBeDefined();
+    });
+
+    it(`existing key should return a result`, () => {
+      expect(argparse.getArgValue('kebab-case-key')).toBe('a value');
+    });
   });
 });

docs/Guide.Jest.md

@@ -16,10 +16,9 @@ npm install --save-dev jest
 
 You should remove `e2e/mocha.opts`, you no longer need it.
 
-### 3. Write a detox setup file
+### 3. Replace generated detox setup file (e2e/init.js)
 
 ```js
-// ./jest/setup/e2e.js
 const detox = require('detox');
 const config = require('../package.json').detox;
 
@@ -44,15 +43,15 @@ beforeEach(async () => {
 Add this part to your `package.json`:
 ```json
 "jest": {
-  "setupTestFrameworkScriptFile": "<rootDir>/jest/setup.js"
+  "setupTestFrameworkScriptFile": "./e2e/init.js"
 },
 "scripts": {
-    "test:e2e": "jest __e2e__ --setupTestFrameworkScriptFile=./jest/setup/e2e-tests.js --runInBand",
+    "test:e2e": "detox test",
     "test:e2e:build": "detox build"
 }
 ```
 
-We need the `--runInBand` as detox doesn't support parallelism yet.
+In the `detox` part of your `package.json`, add `"runner": "jest"` to tell detox that you want to use jest runner instead of mocha.
 
 ### Writing Tests