TUN-3890: Code coverage for cloudflared in CI

Also changed the socks test code so that it binds to localhost, so that
we don't get popups saying "would you like to allow socks.test to use
the network"

.gitignore

@@ -18,3 +18,4 @@ cloudflared-x86-64*
 .DS_Store
 *-session.log
 ssh_server_tests/.env
+.cover

Makefile

@@ -88,7 +88,13 @@ container:
 
 .PHONY: test
 test: vet
+ifndef CI
 	go test -v -mod=vendor -race $(VERSION_FLAGS) ./...
+else
+	@mkdir -p .cover
+	go test -v -mod=vendor -race $(VERSION_FLAGS) -coverprofile=".cover/c.out" ./...
+	go tool cover -html ".cover/c.out" -o .cover/all.html
+endif
 
 .PHONY: test-ssh-server
 test-ssh-server:

hello/hello_test.go

@@ -27,7 +27,7 @@ func TestCreateTLSListenerOnlyHostSuccess(t *testing.T) {
 }
 
 func TestCreateTLSListenerOnlyPortSuccess(t *testing.T) {
-	listener, err := CreateTLSListener(":8888")
+	listener, err := CreateTLSListener("localhost:8888")
 	if err != nil {
 		t.Fatal(err)
 	}

socks/connection_handler_test.go

@@ -42,7 +42,7 @@ func startTestServer(t *testing.T, httpHandler func(w http.ResponseWriter, r *ht
 	// create a socks server
 	requestHandler := NewRequestHandler(NewNetDialer())
 	socksServer := NewConnectionHandler(requestHandler)
-	listener, err := net.Listen("tcp", ":8086")
+	listener, err := net.Listen("tcp", "localhost:8086")
 	assert.NoError(t, err)
 
 	go func() {
@@ -58,7 +58,7 @@ func startTestServer(t *testing.T, httpHandler func(w http.ResponseWriter, r *ht
 	mux.HandleFunc("/", httpHandler)
 
 	// start the servers
-	go http.ListenAndServe(":8085", mux)
+	go http.ListenAndServe("localhost:8085", mux)
 }
 
 func respondWithJSON(w http.ResponseWriter, v interface{}, status int) {