diff --git a/generator/utils_test.go b/generator/utils_test.go
new file mode 100644
index 0000000..f798810
--- /dev/null
+++ b/generator/utils_test.go
@@ -0,0 +1,99 @@
+package generator
+
+import (
+	"fmt"
+	"katenary/generator/labels"
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/compose-spec/compose-go/cli"
+)
+
+func TestSplitPorts(t *testing.T) {
+	composeFileContent := `
+services:
+  foo:
+    image: nginx:latest
+    labels:
+      %[1]s/ports: 80,443
+`
+	composeFileContent = fmt.Sprintf(composeFileContent, labels.KatenaryLabelPrefix)
+	tmpDir, err := os.MkdirTemp("", "katenary-test-override")
+	if err != nil {
+		t.Fatalf(err.Error())
+	}
+	composeFile := filepath.Join(tmpDir, "compose.yaml")
+
+	os.MkdirAll(tmpDir, 0755)
+	if err := os.WriteFile(composeFile, []byte(composeFileContent), 0644); err != nil {
+		t.Log(err)
+	}
+	defer os.RemoveAll(tmpDir)
+
+	// chand dir to this directory
+	os.Chdir(tmpDir)
+	options, _ := cli.NewProjectOptions(nil,
+		cli.WithWorkingDirectory(tmpDir),
+		cli.WithDefaultConfigPath,
+	)
+	project, err := cli.ProjectFromOptions(options)
+	if err := fixPorts(&project.Services[0]); err != nil {
+		t.Errorf("Expected no error, got %s", err)
+	}
+	found := 0
+	for _, p := range project.Services[0].Ports {
+		switch p.Target {
+		case 80, 443:
+			found++
+		}
+	}
+	if found != 2 {
+		t.Errorf("Expected 2 ports, got %d", found)
+	}
+}
+
+func TestSplitPortsWithDefault(t *testing.T) {
+	composeFileContent := `
+services:
+  foo:
+    image: nginx:latest
+    ports:
+      - 8080
+    labels:
+      %[1]s/ports: 80,443
+`
+	composeFileContent = fmt.Sprintf(composeFileContent, labels.KatenaryLabelPrefix)
+	tmpDir, err := os.MkdirTemp("", "katenary-test-override")
+	if err != nil {
+		t.Fatalf(err.Error())
+	}
+	composeFile := filepath.Join(tmpDir, "compose.yaml")
+
+	os.MkdirAll(tmpDir, 0755)
+	if err := os.WriteFile(composeFile, []byte(composeFileContent), 0644); err != nil {
+		t.Log(err)
+	}
+	defer os.RemoveAll(tmpDir)
+
+	// chand dir to this directory
+	os.Chdir(tmpDir)
+	options, _ := cli.NewProjectOptions(nil,
+		cli.WithWorkingDirectory(tmpDir),
+		cli.WithDefaultConfigPath,
+	)
+	project, err := cli.ProjectFromOptions(options)
+	if err := fixPorts(&project.Services[0]); err != nil {
+		t.Errorf("Expected no error, got %s", err)
+	}
+	found := 0
+	for _, p := range project.Services[0].Ports {
+		switch p.Target {
+		case 80, 443, 8080:
+			found++
+		}
+	}
+	if found != 3 {
+		t.Errorf("Expected 3 ports, got %d", found)
+	}
+}