feat(mocha-runner): use default mocha.opts file, support relative imp…

…orts (#1237)

Check if `test/mocha.opts` exists if the no mocha.opts is specified in the stryker config.
Make sure relative imports when using `--require` (same as mocha does it).

Fixes #1046

packages/stryker-mocha-framework/src/MochaTestFramework.ts

@@ -17,6 +17,7 @@ export default class MochaTestFramework implements TestFramework {
   public filter(testSelections: TestSelection[]) {
     const selectedTestNames = testSelections.map(selection => selection.name);
     return `var Mocha = window.Mocha || require('mocha');
+      var describe = Mocha.describe;
       var selectedTestNames = ${JSON.stringify(selectedTestNames)};
       if (window.____mochaAddTest) {
         Mocha.Suite.prototype.addTest = window.____mochaAddTest;

packages/stryker-mocha-runner/README.md

@@ -58,7 +58,7 @@ If you want to load all files recursively: use a globbing expression (`'test/**/
 
 ### `mochaOptions.opts` [`string`]
 
-Default: `undefined`
+Default: `'test/mocha.opts'`
 
 Specify a ['mocha.opts' file](https://mochajs.org/#mochaopts) to be loaded. Options specified directly in your stryker.conf.js file will overrule options from the 'mocha.opts' file.
 

packages/stryker-mocha-runner/src/MochaOptionsLoader.ts

@@ -7,18 +7,26 @@ import MochaRunnerOptions, { mochaOptionsKey } from './MochaRunnerOptions';
 export default class MochaOptionsLoader {
 
   private readonly log = getLogger(MochaOptionsLoader.name);
+  private readonly DEFAULT_MOCHA_OPTS = 'test/mocha.opts';
 
   public load(config: StrykerOptions): MochaRunnerOptions {
     const mochaOptions = Object.assign({}, config[mochaOptionsKey]) as MochaRunnerOptions;
-    if (mochaOptions && mochaOptions.opts) {
-      const optsFileName = path.resolve(mochaOptions.opts);
+    let optsFileName = path.resolve(this.DEFAULT_MOCHA_OPTS);
+
+    if (mochaOptions.opts) {
+      optsFileName = path.resolve(mochaOptions.opts);
+    }
+
+    if (fs.existsSync(optsFileName)) {
       this.log.info(`Loading mochaOpts from "${optsFileName}"`);
       const options = fs.readFileSync(optsFileName, 'utf8');
       return Object.assign(this.parseOptsFile(options), mochaOptions);
+    } else if (mochaOptions.opts) {
+      this.log.error(`Could not load opts from "${optsFileName}". Please make sure opts file exists.`);
     } else {
-      this.log.debug('No mocha opts file specified, not loading additional mocha options (%s.opts was not defined).', mochaOptionsKey);
-      return mochaOptions;
+      this.log.debug('No mocha opts file found, not loading additional mocha options (%s.opts was not defined).', mochaOptionsKey);
     }
+    return mochaOptions;
   }
 
   private parseOptsFile(optsFileContent: string): MochaRunnerOptions {

packages/stryker-mocha-runner/src/MochaTestRunner.ts

@@ -116,7 +116,11 @@ export default class MochaTestRunner implements TestRunner {
 
   private additionalRequires() {
     if (this.mochaRunnerOptions.require) {
-      this.mochaRunnerOptions.require.forEach(LibWrapper.require);
+      const modulesToRequire = this.mochaRunnerOptions.require
+        .map(module => {
+          return module.startsWith('.') ? path.resolve(module) : module;
+        });
+      modulesToRequire.forEach(LibWrapper.require);
     }
   }
 }

packages/stryker-mocha-runner/test/unit/MochaOptionsLoaderSpec.ts

@@ -10,6 +10,7 @@ import { logger, Mock } from '../helpers/mockHelpers';
 describe('MochaOptionsLoader', () => {
 
   let readFileStub: sinon.SinonStub;
+  let existsFileStub: sinon.SinonStub;
   let config: Config;
   let sut: MochaOptionsLoader;
   let log: Mock<logging.Logger>;
@@ -18,6 +19,7 @@ describe('MochaOptionsLoader', () => {
     log = logger();
     sandbox.stub(logging, 'getLogger').returns(log);
     readFileStub = sandbox.stub(fs, 'readFileSync');
+    existsFileStub = sandbox.stub(fs, 'existsSync').returns(true);
     sut = new MochaOptionsLoader();
     config = new Config();
   });
@@ -36,10 +38,29 @@ describe('MochaOptionsLoader', () => {
     expect(fs.readFileSync).calledWith(path.resolve('some/mocha.opts/file'));
   });
 
-  it('should not load a mocha.opts file if not specified', () => {
+  it('should log an error if specified mocha.opts file doesn\'t exist', () => {
+    readFileStub.returns('');
+    existsFileStub.returns(false);
+    config.mochaOptions = {
+      opts: 'some/mocha.opts/file'
+    };
+
+    sut.load(config);
+    expect(log.error).calledWith(`Could not load opts from "${path.resolve('some/mocha.opts/file')}". Please make sure opts file exists.`);
+  });
+
+  it('should load default mocha.opts file if not specified', () => {
+    readFileStub.returns('');
+    sut.load(config);
+    expect(log.info).calledWith(`Loading mochaOpts from "${path.resolve('test/mocha.opts')}"`);
+    expect(fs.readFileSync).calledWith(path.resolve('test/mocha.opts'));
+  });
+
+  it('should not load default mocha.opts file if not found', () => {
+    existsFileStub.returns(false);
     const options = sut.load(config);
     expect(options).deep.eq({});
-    expect(log.debug).calledWith('No mocha opts file specified, not loading additional mocha options (%s.opts was not defined).', 'mochaOptions');
+    expect(log.debug).calledWith('No mocha opts file found, not loading additional mocha options (%s.opts was not defined).', 'mochaOptions');
   });
 
   it('should load `--require` and `-r` properties if specified in mocha.opts file', () => {

packages/stryker-mocha-runner/test/unit/MochaTestRunnerSpec.ts

@@ -98,6 +98,15 @@ describe('MochaTestRunner', () => {
     expect(requireStub).calledWith('babel-register');
   });
 
+  it('should pass and resolve relative require options when constructed', () => {
+    const mochaOptions: MochaRunnerOptions = { require: ['./setup.js', 'babel-register'] };
+    new MochaTestRunner(runnerOptions({ strykerOptions: { mochaOptions } }));
+    const resolvedRequire = path.resolve('./setup.js');
+    expect(requireStub).calledTwice;
+    expect(requireStub).calledWith(resolvedRequire);
+    expect(requireStub).calledWith('babel-register');
+  });
+
   it('should evaluate additional testHooks if required (in global mocha context)', async () => {
     multimatchStub.returns(['']);
     sut = new MochaTestRunner(runnerOptions());