Fix an issue when not assigning the merge result.

Add some tests.

pkg/spec/postgresql.go

@@ -58,7 +58,7 @@ type CloneDescription struct {
 	EndTimestamp string `json:"timestamp,omitempty"`
 }
 
-type userFlags []string
+type UserFlags []string
 
 // PostgresStatus contains status of the PostgreSQL cluster (running, creation failed etc.)
 type PostgresStatus string
@@ -99,7 +99,7 @@ type PostgresSpec struct {
 	UseLoadBalancer     *bool                `json:"useLoadBalancer,omitempty"`
 	ReplicaLoadBalancer bool                 `json:"replicaLoadBalancer,omitempty"`
 	NumberOfInstances   int32                `json:"numberOfInstances"`
-	Users               map[string]userFlags `json:"users"`
+	Users               map[string]UserFlags `json:"users"`
 	MaintenanceWindows  []MaintenanceWindow  `json:"maintenanceWindows,omitempty"`
 	Clone               CloneDescription     `json:"clone"`
 	ClusterName         string               `json:"-"`

pkg/spec/postgresql_test.go

@@ -226,7 +226,7 @@ var unmarshalCluster = []struct {
 				TeamID:              "ACID",
 				AllowedSourceRanges: []string{"127.0.0.1/32"},
 				NumberOfInstances:   2,
-				Users:               map[string]userFlags{"zalando": {"superuser", "createdb"}},
+				Users:               map[string]UserFlags{"zalando": {"superuser", "createdb"}},
 				MaintenanceWindows: []MaintenanceWindow{{
 					Everyday:  false,
 					Weekday:   time.Monday,