Encode and decode fields of union type.

mojom/generators/go/translator/translator.go

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 package translator
 
 import (
         "fmt"
         "log"
         "sort"
@@ skipping 103 matching lines @@
 
         return m
 }
 
 func (t *translator) translateUnionField(mojomField *mojom_types.UnionField) (field UnionFieldTemplate) {
         field.Name = formatName(*mojomField.DeclData.ShortName)
         field.Type = t.translateType(mojomField.Type)
         field.Tag = mojomField.Tag
         field.EncodingInfo = t.encodingInfo(mojomField.Type)
         field.EncodingInfo.setIdentifier("u.Value")
+        if info, ok := field.EncodingInfo.(*unionTypeEncodingInfo); ok {
+                info.nestedUnion = true
+        }
         return field
 }
 
 func (t *translator) encodingInfo(mojomType mojom_types.Type) EncodingInfo {
         return t.encodingInfoNested(mojomType, 0)
 }
 
 func (t *translator) encodingInfoNested(mojomType mojom_types.Type, level int) (info EncodingInfo) {
         switch m := mojomType.(type) {
         default:
@@ skipping 113 matching lines @@
         valueEncodingInfo.elementEncodingInfo.setIdentifier(fmt.Sprintf("value%v", level))
 
         return info
 }
 
 func (t *translator) typeRefEncodingInfo(typeRef mojom_types.TypeReference) (info EncodingInfo) {
         mojomType := t.GetUserDefinedType(*typeRef.TypeKey)
         switch m := mojomType.(type) {
         case *mojom_types.UserDefinedTypeStructType:
                 info = t.structTypeEncodingInfo(m.Value)
+        case *mojom_types.UserDefinedTypeUnionType:
+                info = t.unionTypeEncodingInfo(m.Value)
         }
         info.setNullable(typeRef.Nullable)
         return info
 }
 
 func (t *translator) structTypeEncodingInfo(mojomType mojom_types.MojomStruct) (info *structTypeEncodingInfo) {
         info = new(structTypeEncodingInfo)
         return info
 }
 
+func (t *translator) unionTypeEncodingInfo(mojomType mojom_types.MojomUnion) (info *unionTypeEncodingInfo) {
+        info = new(unionTypeEncodingInfo)
+        return info
+}
+
 // Implements sort.Interface.
 type structFieldSerializationSorter []mojom_types.StructField
 
 func (s structFieldSerializationSorter) Len() int {
         return len(s)
 }
 
 func (s structFieldSerializationSorter) Less(i, j int) bool {
         if s[i].Offset < s[j].Offset {
                 return true
         }
 
         if s[i].Offset == s[j].Offset && s[i].Bit < s[j].Bit {
                 return true
         }
 
         return false
 }
 
 func (s structFieldSerializationSorter) Swap(i, j int) {
         s[i], s[j] = s[j], s[i]
 }