Add GetOwningArena() to compat list and map values

common/values/custom_list_value.cc

@@ -53,6 +53,8 @@ class EmptyListValue final : public common_internal::CompatListValue {
 
   EmptyListValue() = default;
 
+  google::protobuf::Arena* GetOwningArena() const override { return nullptr; }
+
   std::string DebugString() const override { return "[]"; }
 
   bool IsEmpty() const override { return true; }

common/values/custom_map_value.cc

@@ -70,6 +70,8 @@ class EmptyMapValue final : public common_internal::CompatMapValue {
 
   EmptyMapValue() = default;
 
+  google::protobuf::Arena* GetOwningArena() const override { return nullptr; }
+
   std::string DebugString() const override { return "{}"; }
 
   bool IsEmpty() const override { return true; }

common/values/list_value_builder.h

@@ -39,6 +39,9 @@ namespace common_internal {
 // `list_value_builder.cc`.
 class CompatListValue : public CustomListValueInterface,
                         public google::api::expr::runtime::CelList {
+ public:
+  virtual google::protobuf::Arena* GetOwningArena() const = 0;
+
  private:
   NativeTypeId GetNativeTypeId() const final {
     return NativeTypeId::For<CompatListValue>();
@@ -78,6 +81,9 @@ class MutableListValue : public CustomListValueInterface {
 // inheritance and `dynamic_cast`.
 class MutableCompatListValue : public MutableListValue,
                                public google::api::expr::runtime::CelList {
+ public:
+  virtual google::protobuf::Arena* GetOwningArena() const = 0;
+
  private:
   NativeTypeId GetNativeTypeId() const final {
     return NativeTypeId::For<MutableCompatListValue>();

common/values/map_value_builder.h

@@ -39,6 +39,9 @@ namespace common_internal {
 // `map_value_builder.cc`.
 class CompatMapValue : public CustomMapValueInterface,
                        public google::api::expr::runtime::CelMap {
+ public:
+  virtual google::protobuf::Arena* GetOwningArena() const = 0;
+
  private:
   NativeTypeId GetNativeTypeId() const final {
     return NativeTypeId::For<CompatMapValue>();
@@ -78,6 +81,9 @@ class MutableMapValue : public CustomMapValueInterface {
 // inheritance and `dynamic_cast`.
 class MutableCompatMapValue : public MutableMapValue,
                               public google::api::expr::runtime::CelMap {
+ public:
+  virtual google::protobuf::Arena* GetOwningArena() const = 0;
+
  private:
   NativeTypeId GetNativeTypeId() const final {
     return NativeTypeId::For<MutableCompatMapValue>();

common/values/value_builder.cc

@@ -251,6 +251,10 @@ class CompatListValueImpl final : public CompatListValue {
   explicit CompatListValueImpl(ValueVector&& elements)
       : elements_(std::move(elements)) {}
 
+  google::protobuf::Arena* GetOwningArena() const override {
+    return elements_.get_allocator().arena();
+  }
+
   std::string DebugString() const override {
     return absl::StrCat("[", absl::StrJoin(elements_, ", ", ValueFormatter{}),
                         "]");
@@ -388,6 +392,10 @@ class MutableCompatListValueImpl final : public MutableCompatListValue {
   explicit MutableCompatListValueImpl(google::protobuf::Arena* absl_nonnull arena)
       : elements_(arena) {}
 
+  google::protobuf::Arena* GetOwningArena() const override {
+    return elements_.get_allocator().arena();
+  }
+
   std::string DebugString() const override {
     return absl::StrCat("[", absl::StrJoin(elements_, ", ", ValueFormatter{}),
                         "]");
@@ -995,6 +1003,10 @@ class CompatMapValueImpl final : public CompatMapValue {
  public:
   explicit CompatMapValueImpl(ValueFlatHashMap&& map) : map_(std::move(map)) {}
 
+  google::protobuf::Arena* GetOwningArena() const override {
+    return map_.get_allocator().arena();
+  }
+
   std::string DebugString() const override {
     return absl::StrCat("{", absl::StrJoin(map_, ", ", ValueFormatter{}), "}");
   }
@@ -1159,6 +1171,10 @@ class TrivialMutableMapValueImpl final : public MutableCompatMapValue {
   explicit TrivialMutableMapValueImpl(google::protobuf::Arena* absl_nonnull arena)
       : map_(arena) {}
 
+  google::protobuf::Arena* GetOwningArena() const override {
+    return map_.get_allocator().arena();
+  }
+
   std::string DebugString() const override {
     return absl::StrCat("{", absl::StrJoin(map_, ", ", ValueFormatter{}), "}");
   }