newConfFilename:      "istio-cni.conf",
		},
	}

	for _, c := range cases {
		t.Run(c.name, func(t *testing.T) {
			istioConf := testutils.ReadFile(t, filepath.Join("testdata", c.newConfFilename))
			existingConfFilepath := filepath.Join("testdata", c.existingConfFilename)
			existingConf := testutils.ReadFile(t, existingConfFilepath)

			output, err := insertCNIConfig(istioConf, existingConf)
			if err != nil {