Add more tests (#1949)

* add more test code

* add more test code

pkg/simple/client/ldap/interface.go

@@ -0,0 +1,21 @@
+package ldap
+
+import "kubesphere.io/kubesphere/pkg/api/iam"
+
+// Interface defines CRUD behaviors of manipulating users
+type Interface interface {
+	// Create create a new user in ldap
+	Create(user *iam.User) error
+
+	// Update updates a user information, return error if user not exists
+	Update(user *iam.User) error
+
+	// Delete deletes a user from ldap, return nil if user not exists
+	Delete(name string) error
+
+	// Get gets a user by its username from ldap, return ErrUserNotExists if user not exists
+	Get(name string) (*iam.User, error)
+
+	// Verify checks if (name, password) is valid, return ErrInvalidCredentials if not
+	Verify(name string, password string) error
+}