Improve test coverage reporting / accuracy (#7819)

* improve test coverage reporting / accuracy

* handle absolute coverpaths

* move tests into multiple files

* rename codecov.yml (https://github.com/codecov/support/issues/426)

app/web_hub_test.go

@@ -0,0 +1,60 @@
+package app
+
+import (
+	"net"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/gorilla/websocket"
+	goi18n "github.com/nicksnyder/go-i18n/i18n"
+	"github.com/stretchr/testify/require"
+
+	"github.com/mattermost/mattermost-server/model"
+)
+
+func dummyWebsocketHandler(t *testing.T) http.HandlerFunc {
+	return func(w http.ResponseWriter, req *http.Request) {
+		upgrader := &websocket.Upgrader{
+			ReadBufferSize:  1024,
+			WriteBufferSize: 1024,
+		}
+		conn, err := upgrader.Upgrade(w, req, nil)
+		for err == nil {
+			_, _, err = conn.ReadMessage()
+		}
+		if _, ok := err.(*websocket.CloseError); !ok {
+			require.NoError(t, err)
+		}
+	}
+}
+
+func registerDummyWebConn(t *testing.T, a *App, addr net.Addr, userId string) *WebConn {
+	session, appErr := a.CreateSession(&model.Session{
+		UserId: userId,
+	})
+	require.Nil(t, appErr)
+
+	d := websocket.Dialer{}
+	c, _, err := d.Dial("ws://"+addr.String()+"/ws", nil)
+	require.NoError(t, err)
+
+	wc := a.NewWebConn(c, *session, goi18n.IdentityTfunc(), "en")
+	a.HubRegister(wc)
+	go wc.Pump()
+	return wc
+}
+
+func TestHubStopWithMultipleConnections(t *testing.T) {
+	th := Setup().InitBasic()
+	defer th.TearDown()
+
+	s := httptest.NewServer(http.HandlerFunc(dummyWebsocketHandler(t)))
+	defer s.Close()
+
+	th.App.HubStart()
+	registerDummyWebConn(t, th.App, s.Listener.Addr(), th.BasicUser.Id)
+	registerDummyWebConn(t, th.App, s.Listener.Addr(), th.BasicUser.Id)
+	registerDummyWebConn(t, th.App, s.Listener.Addr(), th.BasicUser.Id)
+	th.App.HubStop()
+}