More tests coverage for client.go

client.go

@@ -133,7 +133,6 @@ func NewClient(h string, o ...Option) (*Client, error) {
 	// Some settings in a Client cannot be empty/unset
 	if c.host == "" {
 		return c, ErrNoHostname
-
 	}
 
 	return c, nil

client_test.go

@@ -13,8 +13,19 @@ const DefaultHost = "localhost"
 // TestNewClient tests the NewClient() method with its default options
 func TestNewClient(t *testing.T) {
 	host := "mail.example.com"
-	c, err := NewClient(host)
-	if err != nil {
+	tests := []struct {
+		name       string
+		host       string
+		shouldfail bool
+	}{
+		{"Default", "mail.example.com", false},
+		{"Empty host should fail", "", true},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			c, err := NewClient(tt.host)
+			if err != nil && !tt.shouldfail {
 				t.Errorf("failed to create new client: %s", err)
 				return
 			}
@@ -39,6 +50,8 @@ func TestNewClient(t *testing.T) {
 				t.Errorf("failed to create new client. TLS config min versino expected: %d, got: %d",
 					DefaultTLSMinVersion, c.tlsconfig.MinVersion)
 			}
+		})
+	}
 }
 
 // TestNewClient tests the NewClient() method with its custom options