YT-22885: Refactor checked casts

commit_hash:7f7600d332c3ddb5c8372e921bcba3b4fbed68f8

8 files changed, 122 insertions, 51 deletions

diff --git a/library/cpp/yt/misc/arcadia_enum-inl.h b/library/cpp/yt/misc/arcadia_enum-inl.h
index 17a10bb3b2..1df8b2c464 100644
--- a/library/cpp/yt/misc/arcadia_enum-inl.h
+++ b/library/cpp/yt/misc/arcadia_enum-inl.h
@@ -42,6 +42,18 @@ struct TArcadiaEnumTraitsImpl
         auto it = LiteralToValue.find(literal);
         return it == LiteralToValue.end() ? std::nullopt : std::make_optional(it->second);
     }
+
+    static bool IsKnownValue(T value)
+    {
+        static const auto Values = [] {
+            THashSet<T> result;
+            for (const auto& [value, _] : GetEnumNames<T>()) {
+                result.insert(value);
+            }
+            return result;
+        }();
+        return Values.contains(value);
+    }
 };
 
 ////////////////////////////////////////////////////////////////////////////////
diff --git a/library/cpp/yt/misc/cast-inl.h b/library/cpp/yt/misc/cast-inl.h
index 00e6e240b8..50920f0193 100644
--- a/library/cpp/yt/misc/cast-inl.h
+++ b/library/cpp/yt/misc/cast-inl.h
@@ -94,20 +94,19 @@ constexpr bool IsInIntegralRange(S value)
 }
 
 template <class T, class S>
-constexpr bool TryIntegralCast(S value, T* result)
+constexpr std::optional<T> TryCheckedIntegralCast(S value)
 {
-    if (!NDetail::IsInIntegralRange<T>(value)) {
-        return false;
+    [[unlikely]] if (!NDetail::IsInIntegralRange<T>(value)) {
+        return std::nullopt;
     }
-    *result = static_cast<T>(value);
-    return true;
+    return static_cast<T>(value);
 }
 
 template <class T, class S>
 T CheckedIntegralCast(S value)
 {
-    T result;
-    if (!TryIntegralCast<T>(value, &result)) {
+    auto result = TryCheckedIntegralCast<T>(value);
+    if (!result) {
         throw TSimpleException(Sprintf("Error casting %s value \"%s\" to %s: value is out of expected range [%s; %s]",
             TypeName<S>().c_str(),
             NYT::NDetail::FormatInvalidCastValue(value).c_str(),
@@ -115,35 +114,43 @@ T CheckedIntegralCast(S value)
             ::ToString(std::numeric_limits<T>::lowest()).c_str(),
             ::ToString(std::numeric_limits<T>::max()).c_str()));
     }
-    return result;
+    return *result;
 }
 
 template <class T, class S>
-constexpr bool TryEnumCast(S value, T* result)
+    requires TEnumTraits<T>::IsEnum
+constexpr std::optional<T> TryCheckedEnumCast(S value)
 {
-    std::underlying_type_t<T> underlying;
-    if (!TryIntegralCast<std::underlying_type_t<T>>(value, &underlying)) {
-        return false;
+    auto underlying = TryCheckedIntegralCast<std::underlying_type_t<T>>(value);
+    [[unlikely]] if (!underlying) {
+        return std::nullopt;
     }
-    auto candidate = static_cast<T>(underlying);
-    if (!TEnumTraits<T>::FindLiteralByValue(candidate)) {
-        return false;
+    auto candidate = static_cast<T>(*underlying);
+    [[unlikely]] if (!TEnumTraits<T>::IsValidValue(candidate)) {
+        return std::nullopt;
     }
-    *result = candidate;
-    return true;
+    return candidate;
 }
 
 template <class T, class S>
+    requires TEnumTraits<T>::IsEnum
 T CheckedEnumCast(S value)
 {
-    T result;
-    if (!TryEnumCast<T>(value, &result)) {
-        throw TSimpleException(Sprintf("Error casting %s value \"%d\" to enum %s",
-            TypeName<S>().c_str(),
-            static_cast<int>(value),
-            TEnumTraits<T>::GetTypeName().data()));
+    auto result = TryCheckedEnumCast<T>(value);
+    [[unlikely]] if (!result) {
+        if constexpr (std::is_signed_v<S>) {
+            throw TSimpleException(Sprintf("Error casting %s value \"%" PRIi64 "\" to enum %s",
+                TypeName<S>().c_str(),
+                static_cast<i64>(value),
+                TEnumTraits<T>::GetTypeName().data()));
+        } else {
+            throw TSimpleException(Sprintf("Error casting %s value \"%" PRIu64 "\" to enum %s",
+                TypeName<S>().c_str(),
+                static_cast<ui64>(value),
+                TEnumTraits<T>::GetTypeName().data()));
+        }
     }
-    return result;
+    return *result;
 }
 
 ////////////////////////////////////////////////////////////////////////////////
diff --git a/library/cpp/yt/misc/cast.h b/library/cpp/yt/misc/cast.h
index e8654cc122..a4e32e0287 100644
--- a/library/cpp/yt/misc/cast.h
+++ b/library/cpp/yt/misc/cast.h
@@ -1,7 +1,11 @@
 #pragma once
 
+#include "enum.h"
+
 #include <library/cpp/yt/exception/exception.h>
 
+#include <optional>
+
 namespace NYT {
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -13,7 +17,7 @@ template <class T, class S>
 constexpr bool IsInIntegralRange(S value);
 
 template <class T, class S>
-constexpr bool TryIntegralCast(S value, T* result);
+constexpr std::optional<T> TryCheckedIntegralCast(S value);
 
 template <class T, class S>
 T CheckedIntegralCast(S value);
@@ -21,9 +25,11 @@ T CheckedIntegralCast(S value);
 ////////////////////////////////////////////////////////////////////////////////
 
 template <class T, class S>
-constexpr bool TryEnumCast(S value, T* result);
+    requires TEnumTraits<T>::IsEnum
+constexpr std::optional<T> TryCheckedEnumCast(S value);
 
 template <class T, class S>
+    requires TEnumTraits<T>::IsEnum
 T CheckedEnumCast(S value);
 
 ////////////////////////////////////////////////////////////////////////////////
diff --git a/library/cpp/yt/misc/enum-inl.h b/library/cpp/yt/misc/enum-inl.h
index f1fb9f63e1..d8037bbf74 100644
--- a/library/cpp/yt/misc/enum-inl.h
+++ b/library/cpp/yt/misc/enum-inl.h
@@ -324,6 +324,16 @@ constexpr bool TEnumTraits<T, true>::IsKnownValue(T value)
 }
 
 template <class T>
+constexpr bool TEnumTraits<T, true>::IsValidValue(T value)
+{
+    if constexpr (IsBitEnum) {
+        return (value & TEnumTraits<T>::GetAllSetValue()) == value;
+    } else {
+        return IsKnownValue(value);
+    }
+}
+
+template <class T>
 TString TEnumTraits<T, true>::ToString(T value)
 {
     using ::ToString;
diff --git a/library/cpp/yt/misc/enum.h b/library/cpp/yt/misc/enum.h
index d9611b2823..331eb59f1a 100644
--- a/library/cpp/yt/misc/enum.h
+++ b/library/cpp/yt/misc/enum.h
@@ -89,8 +89,10 @@ struct TEnumTraits<T, true>
     static constexpr std::optional<T> TryGetUnknownValue();
     static std::optional<TStringBuf> FindLiteralByValue(T value);
     static std::optional<T> FindValueByLiteral(TStringBuf literal);
+
     static constexpr bool IsKnownValue(T value)
         requires (!TEnumTraitsImpl<T>::IsBitEnum);
+    static constexpr bool IsValidValue(T value);
 
     static TString ToString(T value);
     static T FromString(TStringBuf literal);
diff --git a/library/cpp/yt/misc/unittests/cast_ut.cpp b/library/cpp/yt/misc/unittests/cast_ut.cpp
new file mode 100644
index 0000000000..8662575d6c
--- /dev/null
+++ b/library/cpp/yt/misc/unittests/cast_ut.cpp
@@ -0,0 +1,45 @@
+#include <library/cpp/testing/gtest/gtest.h>
+
+#include <library/cpp/yt/misc/cast.h>
+#include <library/cpp/yt/misc/enum.h>
+
+namespace NYT {
+namespace {
+
+////////////////////////////////////////////////////////////////////////////////
+
+DEFINE_ENUM_WITH_UNDERLYING_TYPE(ECardinal, char,
+    ((West)  (0))
+    ((North) (1))
+    ((East)  (2))
+    ((South) (3))
+);
+
+DEFINE_BIT_ENUM_WITH_UNDERLYING_TYPE(EFeatures, ui8,
+    ((None)  (0x0000))
+    ((First) (0x0001))
+    ((Second)(0x0002))
+);
+
+TEST(TCastTest, TryCheckedEnumCast)
+{
+    EXPECT_EQ((TryCheckedEnumCast<ECardinal, char>(2)), ECardinal::East);
+    EXPECT_EQ((TryCheckedEnumCast<ECardinal, int>(3)), ECardinal::South);
+
+    EXPECT_FALSE((TryCheckedEnumCast<ECardinal, char>(100)));
+    EXPECT_FALSE((TryCheckedEnumCast<ECardinal, int>(300)));
+
+    EXPECT_EQ((TryCheckedEnumCast<EFeatures, ui8>(0)), EFeatures::None);
+    EXPECT_EQ((TryCheckedEnumCast<EFeatures, ui8>(ToUnderlying(EFeatures::First))), EFeatures::First);
+    EXPECT_EQ((TryCheckedEnumCast<EFeatures, ui8>(ToUnderlying(EFeatures::Second))), EFeatures::Second);
+    EXPECT_EQ((TryCheckedEnumCast<EFeatures, int>(ToUnderlying(EFeatures::First))), EFeatures::First);
+    EXPECT_EQ((TryCheckedEnumCast<EFeatures, ui8>(ToUnderlying(EFeatures::First | EFeatures::Second))), EFeatures::First | EFeatures::Second);
+
+    EXPECT_FALSE((TryCheckedEnumCast<EFeatures, ui8>(0x10)));
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+} // namespace
+} // namespace NYT
+
diff --git a/library/cpp/yt/misc/unittests/enum_ut.cpp b/library/cpp/yt/misc/unittests/enum_ut.cpp
index fc7feed227..22bfe1fdc9 100644
--- a/library/cpp/yt/misc/unittests/enum_ut.cpp
+++ b/library/cpp/yt/misc/unittests/enum_ut.cpp
@@ -215,10 +215,21 @@ TEST(TEnumTest, IsKnownValue)
     EXPECT_TRUE(TEnumTraits<ESimple>::IsKnownValue(ESimple::X));
     EXPECT_TRUE(TEnumTraits<ESimple>::IsKnownValue(ESimple::Y));
     EXPECT_TRUE(TEnumTraits<ESimple>::IsKnownValue(ESimple::Z));
-
     EXPECT_FALSE(TEnumTraits<ESimple>::IsKnownValue(static_cast<ESimple>(100)));
+}
 
-    EXPECT_TRUE(TEnumTraits<EColor>::IsKnownValue(EColor::Red));
+TEST(TEnumTest, IsValidValue)
+{
+    EXPECT_TRUE(TEnumTraits<ESimple>::IsValidValue(ESimple::X));
+    EXPECT_TRUE(TEnumTraits<ESimple>::IsValidValue(ESimple::Y));
+    EXPECT_TRUE(TEnumTraits<ESimple>::IsValidValue(ESimple::Z));
+    EXPECT_FALSE(TEnumTraits<ESimple>::IsValidValue(static_cast<ESimple>(100)));
+
+    EXPECT_TRUE(TEnumTraits<EFlag>::IsValidValue(EFlag()));
+    EXPECT_TRUE(TEnumTraits<EFlag>::IsValidValue(EFlag::_1));
+    EXPECT_TRUE(TEnumTraits<EFlag>::IsValidValue(EFlag::_1 | EFlag::_2));
+    EXPECT_TRUE(TEnumTraits<EFlag>::IsValidValue(EFlag::_1 | EFlag::_2 | EFlag::_3 | EFlag::_4));
+    EXPECT_FALSE(TEnumTraits<EFlag>::IsValidValue(static_cast<EFlag>(0x10)));
 }
 
 TEST(TEnumTest, AllSetValue)
@@ -280,29 +291,6 @@ TEST(TEnumTest, CustomString)
     EXPECT_EQ("1_b", ToString(ECustomString::B));
 }
 
-TEST(TEnumTest, Cast)
-{
-    ECardinal cardinal;
-    {
-        char validValue = 2;
-        EXPECT_TRUE(TryEnumCast(validValue, &cardinal));
-        EXPECT_EQ(cardinal, ECardinal::East);
-    }
-    {
-        char invalidValue = 100;
-        EXPECT_FALSE(TryEnumCast(invalidValue, &cardinal));
-    }
-    {
-        int widerTypeValidValue = 3;
-        EXPECT_TRUE(TryEnumCast(widerTypeValidValue, &cardinal));
-        EXPECT_EQ(cardinal, ECardinal::South);
-    }
-    {
-        int widerTypeInvalueValue = (1 << 8) + 100;
-        EXPECT_FALSE(TryEnumCast(widerTypeInvalueValue, &cardinal));
-    }
-}
-
 TEST(TEnumTest, UnknownValue)
 {
     EXPECT_EQ(TEnumTraits<EColor>::TryGetUnknownValue(), std::nullopt);
diff --git a/library/cpp/yt/misc/unittests/ya.make b/library/cpp/yt/misc/unittests/ya.make
index 5a071c887c..aa6d182c4b 100644
--- a/library/cpp/yt/misc/unittests/ya.make
+++ b/library/cpp/yt/misc/unittests/ya.make
@@ -3,6 +3,7 @@ GTEST(unittester-library-misc)
 INCLUDE(${ARCADIA_ROOT}/library/cpp/yt/ya_cpp.make.inc)
 
 SRCS(
+    cast_ut.cpp
     enum_ut.cpp
     guid_ut.cpp
     non_null_ptr_ut.cpp