Improved API to make config optional

Added tests for TestRunner

index.js

@@ -3,6 +3,5 @@
 const TestRunner = require('./src/TestRunner');
 
 module.exports = (app, config, testSuiteDefinition) => {
-  new TestRunner(config)
-    .run(app, testSuiteDefinition);
+  TestRunner.run(app, config, testSuiteDefinition);
 };

src/TestConfig.js

@@ -18,4 +18,8 @@ module.exports = class TestConfig {
     return Object.assign({}, {url: '/api/users/login'}, this.config.auth);
   }
 
+  static make(config) {
+    return new TestConfig(config);
+  }
+
 };

src/TestRunner.js

@@ -5,12 +5,15 @@ const TestSuite = require('./TestSuite'),
 
 class TestRunner {
 
-  constructor(config) {
-    this.config = new TestConfig(config);
-  }
+  static run(app, config, testSuiteDefinition = {}) {
+    if (arguments.length === 2) {
+      config = {};
+      testSuiteDefinition = arguments[1];
+    }
+
+    config = TestConfig.make(config);
 
-  run(app, testSuiteDefinition = {}) {
-    TestSuite.generate(testSuiteDefinition, this.config)
+    TestSuite.generate(testSuiteDefinition, config)
       .forEach(testSuite => testSuite.run(app));
   }
 

src/TestRunner.test.js

@@ -0,0 +1,62 @@
+'use strict';
+
+const expect = require('chai').expect,
+  sinon = require('sinon');
+
+const TestRunner = require('./TestRunner'),
+  TestConfig = require('./TestConfig'),
+  TestSuite = require('./TestSuite');
+
+describe('TestRunner', () => {
+
+  describe('run', () => {
+
+    let testStubs,
+      config, def, configStub;
+
+    beforeEach(() => {
+      testStubs = [];
+      config = {config: 123};
+      def = {def: 123};
+      configStub = 'configStub';
+
+      sinon.stub(TestSuite, 'generate').callsFake(() => testStubs);
+      sinon.stub(TestConfig, 'make').returns(configStub);
+    });
+
+    afterEach(() => {
+      TestSuite.generate.restore();
+      TestConfig.make.restore();
+    });
+
+    it('calls generate with test suite and config', () => {
+      TestRunner.run('app', config, def);
+
+      expect(TestSuite.generate.calledOnce).to.be.true;
+      expect(TestSuite.generate.calledWithExactly(def, configStub)).to.be.true;
+    });
+
+    it('calls generate with test suite and default config', () => {
+      TestRunner.run('app', def);
+
+      expect(TestSuite.generate.calledOnce).to.be.true;
+      expect(TestSuite.generate.calledWithExactly(def, configStub)).to.be.true;
+    });
+
+    it('calls run(app) on every generated test suites', () => {
+      testStubs = [
+        {run: sinon.spy()},
+        {run: sinon.spy()}
+      ];
+
+      TestRunner.run('app', config, def);
+
+      testStubs.forEach(stub => {
+        expect(stub.run.calledOnce).to.be.true;
+        expect(stub.run.calledWithExactly('app')).to.be.true;
+      });
+    });
+
+  });
+
+});