govc: Fix incorrect MoRef parsing

Closes: #2538
Signed-off-by: Michael Gasch <mgasch@vmware.com>

govc/flags/datacenter.go

@@ -197,12 +197,12 @@ func (flag *DatacenterFlag) ManagedObjects(ctx context.Context, args []string) (
 	}
 
 	for _, arg := range args {
-		var ref types.ManagedObjectReference
-		if ref.FromString(arg) {
+		if ref := object.ReferenceFromString(arg); ref != nil {
 			// e.g. output from object.collect
-			refs = append(refs, ref)
+			refs = append(refs, *ref)
 			continue
 		}
+
 		elements, err := finder.ManagedObjectList(ctx, arg)
 		if err != nil {
 			return nil, err

govc/test/vm.bats

@@ -120,6 +120,12 @@ load test_helper
 
   run govc vm.create -force -cluster DC0_C0 "$id"
   assert_success # create vm with the same name
+
+  run govc vm.create -cluster DC0_C0 "my:vm"
+  assert_success # vm has special characters (moref)
+
+  run govc object.collect -s vm/my:vm name
+  assert_success my:vm
 }
 
 @test "vm.change" {

object/common.go

@@ -25,6 +25,7 @@ import (
 	"github.com/vmware/govmomi/property"
 	"github.com/vmware/govmomi/vim25"
 	"github.com/vmware/govmomi/vim25/methods"
+	"github.com/vmware/govmomi/vim25/mo"
 	"github.com/vmware/govmomi/vim25/types"
 )
 
@@ -134,3 +135,14 @@ func (c Common) SetCustomValue(ctx context.Context, key string, value string) er
 	_, err := methods.SetCustomValue(ctx, c.c, &req)
 	return err
 }
+
+func ReferenceFromString(s string) *types.ManagedObjectReference {
+	var ref types.ManagedObjectReference
+	if !ref.FromString(s) {
+		return nil
+	}
+	if mo.IsManagedObjectType(ref.Type) {
+		return &ref
+	}
+	return nil
+}

vim25/mo/type_info.go

@@ -256,3 +256,8 @@ func (t *typeInfo) LoadFromObjectContent(o types.ObjectContent) (reflect.Value,
 
 	return v, nil
 }
+
+func IsManagedObjectType(kind string) bool {
+	_, ok := t[kind]
+	return ok
+}

vim25/types/helpers.go

@@ -54,7 +54,7 @@ func (r ManagedObjectReference) String() string {
 func (r *ManagedObjectReference) FromString(o string) bool {
 	s := strings.SplitN(o, ":", 2)
 
-	if len(s) < 2 {
+	if len(s) != 2 {
 		return false
 	}