Add tests for sessions

Makefile

@@ -4,7 +4,7 @@ all:
 	go build -o telegabber
 
 test:
-	go test -v ./config ./ ./telegram ./xmpp/gateway
+	go test -v ./config ./ ./telegram ./xmpp/gateway ./persistence
 
 lint:
 	$(GOPATH)/bin/golint ./...

persistence/sessions_test.go

@@ -0,0 +1,79 @@
+package persistence
+
+import (
+	"reflect"
+	"testing"
+)
+
+func TestEmptySessionsMap(t *testing.T) {
+	var sm SessionsMap
+	emptySessionsMap(&sm)
+	if sm.Sessions == nil {
+		t.Error("Session map is still empty!")
+	}
+}
+
+func TestNoEmptySessionsMap(t *testing.T) {
+	var sm SessionsMap
+	if sm.Sessions != nil {
+		t.Error("Session map is not empty at start!")
+	}
+}
+
+func TestSessionGet(t *testing.T) {
+	session := Session{
+		Timezone: "klsf",
+	}
+	tz, err := session.Get("timezone")
+	if err != nil {
+		t.Error(err)
+	}
+	if tz != "klsf" {
+		t.Errorf("Wrong value from session: %s", tz)
+	}
+}
+
+func TestSessionGetAbsent(t *testing.T) {
+	session := Session{
+		Timezone: "klsf",
+	}
+	_, err := session.Get("donkey")
+	if err == nil {
+		t.Error("There shouldn't be a donkey!")
+	}
+}
+
+func TestSessionToMap(t *testing.T) {
+	session := Session{
+		Timezone: "klsf",
+	}
+	m := session.ToMap()
+	sample := map[string]string{
+		"timezone": "klsf",
+	}
+	if !reflect.DeepEqual(m, sample) {
+		t.Errorf("Map does not match the sample: %v", m)
+	}
+}
+
+func TestSessionSet(t *testing.T) {
+	session := Session{}
+	tz, err := session.Set("timezone", "zaz")
+	if err != nil {
+		t.Error(err)
+	}
+	if tz != "zaz" {
+		t.Errorf("Wrong set result: %s", tz)
+	}
+	if session.Timezone != "zaz" {
+		t.Errorf("Wrong actual value in the session: %s", session.Timezone)
+	}
+}
+
+func TestSessionSetAbsent(t *testing.T) {
+	session := Session{}
+	_, err := session.Set("donkey", "zaz")
+	if err == nil {
+		t.Error("There shouldn't come a donkey!")
+	}
+}