func NetworkInterfacePostCloneOperation(d *schema.ResourceData, c *govmomi.Client, l object.VirtualDeviceList) (object.VirtualDeviceList, []types.BaseVirtualDeviceConfigSpec, error) {
	log.Printf("[DEBUG] NetworkInterfacePostCloneOperation: Looking for post-clone device changes")
	devices := l.Select(func(device types.BaseVirtualDevice) bool {
		if _, ok := device.(types.BaseVirtualEthernetCard); ok {
			return true
		}
		return false
	})
	log.Printf("[DEBUG] NetworkInterfacePostCloneOperation: Network devices located: %s", DeviceListString(devices))
	curSet := d.Get(subresourceTypeNetworkInterface).([]interface{})
	log.Printf("[DEBUG] NetworkInterfacePostCloneOperation: Current resource set from configuration: %s", subresourceListString(curSet))
	urange, err := nicUnitRange(devices)
	if err != nil {
		return nil, nil, fmt.Errorf("error calculating network device range: %s", err)
	}
	srcSet := make([]interface{}, urange)
	log.Printf("[DEBUG] NetworkInterfacePostCloneOperation: Layout from source: %d devices over a %d unit range", len(devices), urange)

	// Populate the source set as if the devices were orphaned. This give us a
	// base to diff off of.
	log.Printf("[DEBUG] NetworkInterfacePostCloneOperation: Reading existing devices")
	for n, device := range devices {
		m := make(map[string]interface{})
		vd := device.GetVirtualDevice()
		ctlr := l.FindByKey(vd.ControllerKey)
		if ctlr == nil {
			return nil, nil, fmt.Errorf("could not find controller with key %d", vd.Key)
		}
		m["key"] = int(vd.Key)
		var err error
		m["device_address"], err = computeDevAddr(vd, ctlr.(types.BaseVirtualController))
		if err != nil {
			return nil, nil, fmt.Errorf("error computing device address: %s", err)
		}
		r := NewNetworkInterfaceSubresource(c, d, m, nil, n)
		if err := r.Read(l); err != nil {
			return nil, nil, fmt.Errorf("%s: %s", r.Addr(), err)
		}
		_, _, idx, err := splitDevAddr(r.Get("device_address").(string))
		if err != nil {
			return nil, nil, fmt.Errorf("%s: error parsing device address: %s", r, err)
		}
		srcSet[idx-networkInterfacePciDeviceOffset] = r.Data()
	}

	// Now go over our current set, kind of treating it like an apply:
	//
	// * No source data at the index is a create
	// * Source data at the index is an update if it has changed
	// * Data at the source with the same data after patching config data is a
	// no-op, but we still push the device's state
	var spec []types.BaseVirtualDeviceConfigSpec
	var updates []interface{}
	for i, ci := range curSet {
		cm := ci.(map[string]interface{})
		if i > len(srcSet)-1 || srcSet[i] == nil {
			// New device
			r := NewNetworkInterfaceSubresource(c, d, cm, nil, i)
			cspec, err := r.Create(l)
			if err != nil {
				return nil, nil, fmt.Errorf("%s: %s", r.Addr(), err)
			}
			l = applyDeviceChange(l, cspec)
			spec = append(spec, cspec...)
			updates = append(updates, r.Data())
			continue
		}
		sm := srcSet[i].(map[string]interface{})
		nc, err := copystructure.Copy(sm)
		if err != nil {
			return nil, nil, fmt.Errorf("error copying source network interface state data at index %d: %s", i, err)
		}
		nm := nc.(map[string]interface{})
		for k, v := range cm {
			// Skip key and device_address here
			switch k {
			case "key", "device_address":
				continue
			}
			nm[k] = v
		}
		r := NewNetworkInterfaceSubresource(c, d, nm, sm, i)
		if !reflect.DeepEqual(sm, nm) {
			// Update
			cspec, err := r.Update(l)
			if err != nil {
				return nil, nil, fmt.Errorf("%s: %s", r.Addr(), err)
			}
			l = applyDeviceChange(l, cspec)
			spec = append(spec, cspec...)
		}
		updates = append(updates, r.Data())
	}

	// Any other device past the end of the network devices listed in config needs to be removed.
	if len(curSet) < len(srcSet) {
		for i, si := range srcSet[len(curSet):] {
			sm := si.(map[string]interface{})
			r := NewNetworkInterfaceSubresource(c, d, sm, nil, i+len(curSet))
			dspec, err := r.Delete(l)
			if err != nil {
				return nil, nil, fmt.Errorf("%s: %s", r.Addr(), err)
			}
			l = applyDeviceChange(l, dspec)
			spec = append(spec, dspec...)
		}
	}

	log.Printf("[DEBUG] NetworkInterfacePostCloneOperation: Post-clone final resource list: %s", subresourceListString(updates))
	// We are now done! Return the updated device list and config spec. Save updates as well.
	if err := d.Set(subresourceTypeNetworkInterface, updates); err != nil {
		return nil, nil, err
	}
	log.Printf("[DEBUG] NetworkInterfacePostCloneOperation: Device list at end of operation: %s", DeviceListString(l))
	log.Printf("[DEBUG] NetworkInterfacePostCloneOperation: Device config operations from post-clone: %s", DeviceChangeString(spec))
	log.Printf("[DEBUG] NetworkInterfacePostCloneOperation: Operation complete, returning updated spec")
	return l, spec, nil
}
func NetworkInterfacePostCloneOperation(d *schema.ResourceData, c *govmomi.Client, l object.VirtualDeviceList) (object.VirtualDeviceList, []types.BaseVirtualDeviceConfigSpec, error) {
	log.Printf("[DEBUG] NetworkInterfacePostCloneOperation: Looking for post-clone device changes")
	devices := l.Select(func(device types.BaseVirtualDevice) bool {
		if _, ok := device.(types.BaseVirtualEthernetCard); ok {
			return true
		}
		return false
	})
	log.Printf("[DEBUG] NetworkInterfacePostCloneOperation: Network devices located: %s", DeviceListString(devices))
	curSet := d.Get(subresourceTypeNetworkInterface).([]interface{})
	log.Printf("[DEBUG] NetworkInterfacePostCloneOperation: Current resource set from configuration: %s", subresourceListString(curSet))
	urange, err := nicUnitRange(devices)
	if err != nil {
		return nil, nil, fmt.Errorf("error calculating network device range: %s", err)
	}
	srcSet := make([]interface{}, urange)
	log.Printf("[DEBUG] NetworkInterfacePostCloneOperation: Layout from source: %d devices over a %d unit range", len(devices), urange)

	// Populate the source set as if the devices were orphaned. This give us a
	// base to diff off of.
	log.Printf("[DEBUG] NetworkInterfacePostCloneOperation: Reading existing devices")
	for n, device := range devices {
		m := make(map[string]interface{})
		vd := device.GetVirtualDevice()
		ctlr := l.FindByKey(vd.ControllerKey)
		if ctlr == nil {
			return nil, nil, fmt.Errorf("could not find controller with key %d", vd.Key)
		}
		m["key"] = int(vd.Key)
		var err error
		m["device_address"], err = computeDevAddr(vd, ctlr.(types.BaseVirtualController))
		if err != nil {
			return nil, nil, fmt.Errorf("error computing device address: %s", err)
		}
		r := NewNetworkInterfaceSubresource(c, d, m, nil, n)
		if err := r.Read(l); err != nil {
			return nil, nil, fmt.Errorf("%s: %s", r.Addr(), err)
		}
		_, _, idx, err := splitDevAddr(r.Get("device_address").(string))
		if err != nil {
			return nil, nil, fmt.Errorf("%s: error parsing device address: %s", r, err)
		}
		srcSet[idx-networkInterfacePciDeviceOffset] = r.Data()
	}

	// Now go over our current set, kind of treating it like an apply:
	//
	// * No source data at the index is a create
	// * Source data at the index is an update if it has changed
	// * Data at the source with the same data after patching config data is a
	// no-op, but we still push the device's state
	var spec []types.BaseVirtualDeviceConfigSpec
	var updates []interface{}
	for i, ci := range curSet {
		cm := ci.(map[string]interface{})
		if i > len(srcSet)-1 || srcSet[i] == nil {
			// New device
			r := NewNetworkInterfaceSubresource(c, d, cm, nil, i)
			cspec, err := r.Create(l)
			if err != nil {
				return nil, nil, fmt.Errorf("%s: %s", r.Addr(), err)
			}
			l = applyDeviceChange(l, cspec)
			spec = append(spec, cspec...)
			updates = append(updates, r.Data())
			continue
		}
		sm := srcSet[i].(map[string]interface{})
		nc, err := copystructure.Copy(sm)
		if err != nil {
			return nil, nil, fmt.Errorf("error copying source network interface state data at index %d: %s", i, err)
		}
		nm := nc.(map[string]interface{})
		for k, v := range cm {
			// Skip key and device_address here
			switch k {
			case "key", "device_address":
				continue
			}
			nm[k] = v
		}
		r := NewNetworkInterfaceSubresource(c, d, nm, sm, i)
		if !reflect.DeepEqual(sm, nm) {
			// Update
			cspec, err := r.Update(l)
			if err != nil {
				return nil, nil, fmt.Errorf("%s: %s", r.Addr(), err)
			}
			l = applyDeviceChange(l, cspec)
			spec = append(spec, cspec...)
		}
		updates = append(updates, r.Data())
	}

	// Any other device past the end of the network devices listed in config needs to be removed.
	if len(curSet) < len(srcSet) {
		for i, si := range srcSet[len(curSet):] {
			sm := si.(map[string]interface{})
			r := NewNetworkInterfaceSubresource(c, d, sm, nil, i+len(curSet))
			dspec, err := r.Delete(l)
			if err != nil {
				return nil, nil, fmt.Errorf("%s: %s", r.Addr(), err)
			}
			l = applyDeviceChange(l, dspec)
			spec = append(spec, dspec...)
		}
	}

	log.Printf("[DEBUG] NetworkInterfacePostCloneOperation: Post-clone final resource list: %s", subresourceListString(updates))
	// We are now done! Return the updated device list and config spec. Save updates as well.
	if err := d.Set(subresourceTypeNetworkInterface, updates); err != nil {
		return nil, nil, err
	}
	log.Printf("[DEBUG] NetworkInterfacePostCloneOperation: Device list at end of operation: %s", DeviceListString(l))
	log.Printf("[DEBUG] NetworkInterfacePostCloneOperation: Device config operations from post-clone: %s", DeviceChangeString(spec))
	log.Printf("[DEBUG] NetworkInterfacePostCloneOperation: Operation complete, returning updated spec")
	return l, spec, nil
}
// NetworkInterfacePostCloneOperation normalizes the network interfaces on a
// freshly-cloned virtual machine and outputs any necessary device change
// operations. It also sets the state in advance of the post-create read.
//
// This differs from a regular apply operation in that a configuration is
// already present, but we don't have any existing state, which the standard
// virtual device operations rely pretty heavily on.