t.Errorf("default providers deep merge failed, got %v", got.DefaultProviders.GetMetrics())
	}
	if !cmp.Equal(getExtensionProviders(got.ExtensionProviders), []string{"prometheus", "stackdriver", "envoy", "sd"}, protocmp.Transform()) {
		t.Errorf("extension providers deep merge failed, got %v", getExtensionProviders(got.ExtensionProviders))
	}
	if len(got.TrustDomainAliases) != 2 {
		t.Errorf("trust domain aliases deep merge failed")
	}

	newMC := &meshconfig.MeshConfig{}
	if err := protomarshal.ApplyYAML(providerYAML, newMC); err != nil {
		return err
	}

	providerNames := sets.New[string]()
	for _, p := range newMC.GetExtensionProviders() {
		providerNames.Insert(p.Name)
	}

	return ist.UpdateMeshConfig(ctx,
		func(mc *meshconfig.MeshConfig) error {
			newProviders := []*meshconfig.MeshConfig_ExtensionProvider{}