feat(server): Add stop method (#3153)

Fix #3149

Author: filipesilva

Diff for: lib/server.js

@@ -263,6 +263,11 @@ class Server extends KarmaEventEmitter {
       }
     })
 
+    this.on('stop', function (done) {
+      this.log.debug('Received stop event, exiting.')
+      return disconnectBrowsers().then(done)
+    })
+
     if (config.singleRun) {
       this.on('browser_restart_failure', (completedBrowser) => {
         singleRunDoneBrowsers[completedBrowser.id] = true
@@ -327,14 +332,17 @@ class Server extends KarmaEventEmitter {
         done(code || 0)
       }
 
-      this.emitAsync('exit').then(() => {
-        socketServer.sockets.removeAllListeners()
-        socketServer.close()
-        const closeTimeout = setTimeout(removeAllListeners, webServerCloseTimeout)
+      return this.emitAsync('exit').then(() => {
+        return new Promise((resolve, reject) => {
+          socketServer.sockets.removeAllListeners()
+          socketServer.close()
+          const closeTimeout = setTimeout(removeAllListeners, webServerCloseTimeout)
 
-        webServer.close(() => {
-          clearTimeout(closeTimeout)
-          removeAllListeners()
+          webServer.close(() => {
+            clearTimeout(closeTimeout)
+            removeAllListeners()
+            resolve()
+          })
         })
       })
     }
@@ -373,6 +381,10 @@ class Server extends KarmaEventEmitter {
     child.unref()
   }
 
+  stop () {
+    return this.emitAsync('stop')
+  }
+
   static start (cliOptions, done) {
     console.warn('Deprecated static method to be removed in v3.0')
     return new Server(cliOptions, done).start()

Diff for: test/unit/server.spec.js

@@ -152,6 +152,25 @@ describe('server', () => {
     })
   })
 
+  describe('start on watch mode', () => {
+    var config
+    beforeEach(() => {
+      config = { port: 9876, listenAddress: '127.0.0.1', singleRun: false }
+      sinon.spy(BundleUtils, 'bundleResourceIfNotExist')
+      sinon.stub(NetUtils, 'bindAvailablePort').resolves(mockBoundServer)
+      sinon.stub(mockBoundServer, 'address').returns({ port: 9877 })
+      sinon
+        .stub(server, 'get')
+        .withArgs('config').returns(config)
+    })
+
+    it('should exit gracefully', (done) => {
+      server.start()
+        .then(() => server.stop())
+        .then(() => done())
+    })
+  })
+
   // ============================================================================
   // server._start()
   // ============================================================================