From 59b8ff3945ede83a7792ded99efbaf98ab418c98 Mon Sep 17 00:00:00 2001
From: ubyte <swarmer@ydb.tech>
Date: Fri, 31 Oct 2025 11:54:32 +0300
Subject: [PATCH] speed up the TValue::HasValue method (#27748)

LOGBROKER-10046
---
 ydb/public/lib/value/ut/value_ut.cpp |  9 ++++++
 ydb/public/lib/value/ut/ya.make      | 13 +++++++++
 ydb/public/lib/value/value.cpp       | 42 ++++++++++++++++++++++++++--
 ydb/public/lib/value/value.h         | 17 ++---------
 ydb/public/lib/value/ya.make         |  4 +++
 5 files changed, 68 insertions(+), 17 deletions(-)
 create mode 100644 ydb/public/lib/value/ut/value_ut.cpp
 create mode 100644 ydb/public/lib/value/ut/ya.make

diff --git a/ydb/public/lib/value/ut/value_ut.cpp b/ydb/public/lib/value/ut/value_ut.cpp
new file mode 100644
index 000000000000..ba2a371ab95d
--- /dev/null
+++ b/ydb/public/lib/value/ut/value_ut.cpp
@@ -0,0 +1,9 @@
+
+#include <ydb/public/lib/value/value.h>
+#include <ydb/library/mkql_proto/protos/minikql.pb.h>
+
+#include <library/cpp/testing/gtest/gtest.h>
+
+TEST(TValue, FieldsCount) {
+    ASSERT_EQ(NKikimrMiniKQL::TValue::GetDescriptor()->field_count(), 18) << "update the NKikimr::NClient::TValue wrapper to support new fields";
+}
diff --git a/ydb/public/lib/value/ut/ya.make b/ydb/public/lib/value/ut/ya.make
new file mode 100644
index 000000000000..b44e9c967d99
--- /dev/null
+++ b/ydb/public/lib/value/ut/ya.make
@@ -0,0 +1,13 @@
+GTEST()
+
+SIZE(SMALL)
+
+PEERDIR(
+    ydb/public/lib/value
+)
+
+SRCS(
+    value_ut.cpp
+)
+
+END()
diff --git a/ydb/public/lib/value/value.cpp b/ydb/public/lib/value/value.cpp
index 96339970ab90..9ead53467836 100644
--- a/ydb/public/lib/value/value.cpp
+++ b/ydb/public/lib/value/value.cpp
@@ -4,10 +4,14 @@
 
 #include <library/cpp/string_utils/base64/base64.h>
 
+#include <google/protobuf/text_format.h>
+
 #include <util/charset/utf8.h>
+#include <util/string/builder.h>
 #include <util/string/cast.h>
 #include <util/string/escape.h>
 #include <util/string/printf.h>
+#include <util/stream/output.h>
 #include <ydb-cpp-sdk/client/value/value.h>
 
 namespace NKikimr {
@@ -28,6 +32,24 @@ TValue TValue::Create(const NKikimrMiniKQL::TResult& result) {
     return TValue::Create(result.GetValue(), result.GetType());
 }
 
+static bool ValueProtobufHasEmptyPayload(const NKikimrMiniKQL::TValue& value) {
+    bool emptyPayload = true;
+    emptyPayload &= (value.value_value_case() == value.VALUE_VALUE_NOT_SET);
+    emptyPayload &= value.GetList().empty();
+    emptyPayload &= value.GetTuple().empty();
+    emptyPayload &= value.GetStruct().empty();
+    emptyPayload &= value.GetDict().empty();
+    emptyPayload &= !value.HasHi128();
+    emptyPayload &= !value.HasVariantIndex();
+    // Non-empty unknown fields are a weird case, as they are not accessible through the wrapper and can only be viewed in the debug dump.
+    // If the value is not considered empty, the wrapper will return a non-empty value, for which no accessor can return a meaningful value.
+    constexpr bool checkUnknownFields = false;
+    if (checkUnknownFields) {
+        emptyPayload = emptyPayload && value.unknown_fields().empty();
+    }
+    return emptyPayload;
+}
+
 bool TValue::HaveValue() const {
     return !IsNull();
 }
@@ -35,7 +57,8 @@ bool TValue::HaveValue() const {
 bool TValue::IsNull() const {
     if (&Value == &Null)
         return true;
-    return Value.ByteSize() == 0;
+
+    return ValueProtobufHasEmptyPayload(Value);
 }
 
 TValue TValue::operator [](const char* name) const {
@@ -108,6 +131,21 @@ TVector<TString> TValue::GetMembersNames() const {
     return members;
 }
 
+TString TValue::DumpToString() const {
+    TStringBuilder dump;
+    TString res;
+    ::google::protobuf::TextFormat::PrintToString(Type, &res);
+    dump << "Type:" << Endl << res << Endl;
+    ::google::protobuf::TextFormat::PrintToString(Value, &res);
+    dump << "Value:" << Endl << res << Endl;
+    return std::move(dump);
+}
+
+void TValue::DumpValue() const {
+    Cerr << DumpToString();
+}
+
+
 TWriteValue TWriteValue::Create(NKikimrMiniKQL::TValue& value, NKikimrMiniKQL::TType& type) {
     return TWriteValue(value, type);
 }
@@ -453,7 +491,7 @@ TString TValue::GetDataText() const {
     case NScheme::NTypeIds::Datetime64:
     case NScheme::NTypeIds::Timestamp64:
     case NScheme::NTypeIds::Interval64:
-        return ToString(Value.GetInt64());        
+        return ToString(Value.GetInt64());
     case NScheme::NTypeIds::JsonDocument:
         return "\"<JsonDocument>\"";
     case NScheme::NTypeIds::Uuid:
diff --git a/ydb/public/lib/value/value.h b/ydb/public/lib/value/value.h
index 4d60789e9431..ff1f93efacc7 100644
--- a/ydb/public/lib/value/value.h
+++ b/ydb/public/lib/value/value.h
@@ -4,9 +4,6 @@
 #include <ydb/public/lib/scheme_types/scheme_type_id.h>
 
 #include <util/generic/vector.h>
-#include <util/string/builder.h>
-
-#include <google/protobuf/text_format.h>
 
 namespace NKikimr {
 namespace NClient {
@@ -106,19 +103,9 @@ class TValue {
     // returns member index by name
     int GetMemberIndex(TStringBuf name) const;
 
-    TString DumpToString() const {
-        TStringBuilder dump;
-        TString res;
-        ::google::protobuf::TextFormat::PrintToString(Type, &res);
-        dump << "Type:" << Endl << res << Endl;
-        ::google::protobuf::TextFormat::PrintToString(Value, &res);
-        dump << "Value:" << Endl << res << Endl;
-        return std::move(dump);
-    }
+    TString DumpToString() const;
 
-    void DumpValue() const {
-        Cerr << DumpToString();
-    }
+    void DumpValue() const; // dump value to stderr
 
     const NKikimrMiniKQL::TType& GetType() const { return Type; };
     const NKikimrMiniKQL::TValue& GetValue() const { return Value; };
diff --git a/ydb/public/lib/value/ya.make b/ydb/public/lib/value/ya.make
index 11d101454244..481a9c149bf8 100644
--- a/ydb/public/lib/value/ya.make
+++ b/ydb/public/lib/value/ya.make
@@ -14,3 +14,7 @@ PEERDIR(
 )
 
 END()
+
+RECURSE_FOR_TESTS(
+    ut
+)