fix(ci): stop the proxy before killing the child, handle errors (#3472)

This should fix #3464, hopefully. Since the test is flaky and only on Travis
we can't be sure until we try for awhile.

test/e2e/step_definitions/hooks.js

@@ -4,12 +4,13 @@ cucumber.defineSupportCode((a) => {
   a.After(function (scenario, callback) {
     const running = this.child != null && typeof this.child.kill === 'function'
 
-    if (running) {
-      this.child.kill()
-      this.child = null
-    }
-
     // stop the proxy if it was started
-    this.proxy.stop(callback)
+    this.proxy.stop(() => {
+      if (running) {
+        this.child.kill()
+        this.child = null
+      }
+      callback()
+    })
   })
 })

test/e2e/support/proxy.js

@@ -9,6 +9,10 @@ function Proxy () {
     target: 'http://localhost:9876'
   })
 
+  self.proxy.on('error', function proxyError (err, req, res) {
+    console.log('support/proxy onerror', err)
+  })
+
   self.server = http.createServer(function (req, res) {
     const url = req.url
     const match = url.match(self.proxyPathRegExp)
@@ -22,6 +26,10 @@ function Proxy () {
     }
   })
 
+  self.server.on('clientError', (err, socket) => {
+    console.log('support/proxy clientError', err)
+  })
+
   self.start = function (port, proxyPath, callback) {
     self.proxyPathRegExp = new RegExp('^' + proxyPath + '(.*)')
     self.server.listen(port, function (error) {