From cf886d8ced474a1a80a985587af251a39701d1b2 Mon Sep 17 00:00:00 2001
From: Dmitry Kardymon <d.kardymon@arenadata.io>
Date: Tue, 6 Jun 2023 11:08:21 +0000
Subject: [PATCH] Remove IsConvertible()

---
 src/Functions/DateTimeTransforms.h  | 46 +++++++++++++++--------------
 src/Functions/FunctionsConversion.h | 41 -------------------------
 2 files changed, 24 insertions(+), 63 deletions(-)

diff --git a/src/Functions/DateTimeTransforms.h b/src/Functions/DateTimeTransforms.h
index d154dd9ffa2..823272e0324 100644
--- a/src/Functions/DateTimeTransforms.h
+++ b/src/Functions/DateTimeTransforms.h
@@ -1444,31 +1444,33 @@ struct Transformer
 
         for (size_t i = 0; i < size; ++i)
         {
-            constexpr bool transformHasIsConvertible = requires(const Transform& t)
+            if constexpr (std::is_same_v<Additions, DateTimeAccurateConvertStrategyAdditions>
+                || std::is_same_v<Additions, DateTimeAccurateOrNullConvertStrategyAdditions>)
             {
-                t.IsConvertible(vec_from[i], time_zone);
-            };
+                bool check_range_result = true;
 
-            if constexpr (transformHasIsConvertible)
-            {
-                if constexpr (std::is_same_v<Additions, DateTimeAccurateConvertStrategyAdditions>
-                    || std::is_same_v<Additions, DateTimeAccurateOrNullConvertStrategyAdditions>)
+                if constexpr (std::is_same_v<ToType, DataTypeDate>)
                 {
-                    bool checked = transform.IsConvertible(vec_from[i], time_zone);
-                    if (!checked)
+                    check_range_result = vec_from[i] >= 0 && vec_from[i] <= DATE_LUT_MAX_DAY_NUM;
+                }
+                else if constexpr (std::is_same_v<ToType, DataTypeDateTime>)
+                {
+                    check_range_result = vec_from[i] >= 0 && vec_from[i] <= 0xFFFFFFFFL;
+                }
+
+                if (!check_range_result)
+                {
+                    if (std::is_same_v<Additions, DateTimeAccurateOrNullConvertStrategyAdditions>)
                     {
-                        if (std::is_same_v<Additions, DateTimeAccurateOrNullConvertStrategyAdditions>)
-                        {
-                            vec_to[i] = 0;
-                            if (vec_null_map_to)
-                                (*vec_null_map_to)[i] = true;
-                            continue;
-                        }
-                        else
-                        {
-                            throw Exception(ErrorCodes::CANNOT_CONVERT_TYPE, "Value in column {} cannot be safely converted into type {}",
-                                TypeName<typename FromTypeVector::value_type>, TypeName<ValueType>);
-                        }
+                        vec_to[i] = 0;
+                        if (vec_null_map_to)
+                            (*vec_null_map_to)[i] = true;
+                        continue;
+                    }
+                    else
+                    {
+                        throw Exception(ErrorCodes::CANNOT_CONVERT_TYPE, "Value in column {} cannot be safely converted into type {}",
+                            TypeName<FromType>, TypeName<ToType>);
                     }
                 }
             }
@@ -1488,7 +1490,7 @@ struct DateTimeTransformImpl
     static ColumnPtr execute(
         const ColumnsWithTypeAndName & arguments, const DataTypePtr & result_type, size_t /*input_rows_count*/, const Transform & transform = {})
     {
-        using Op = Transformer<typename FromDataType::FieldType, typename ToDataType::FieldType, Transform, is_extended_result, Additions>;
+        using Op = Transformer<FromDataType, ToDataType, Transform, is_extended_result, Additions>;
 
         const ColumnPtr source_col = arguments[0].column;
         if (const auto * sources = checkAndGetColumn<typename FromDataType::ColumnType>(source_col.get()))
diff --git a/src/Functions/FunctionsConversion.h b/src/Functions/FunctionsConversion.h
index 6aa5843ff65..3a8ddcc9094 100644
--- a/src/Functions/FunctionsConversion.h
+++ b/src/Functions/FunctionsConversion.h
@@ -365,22 +365,11 @@ template <typename Name> struct ConvertImpl<DataTypeDate32, DataTypeDateTime, Na
 
 /// Implementation of toDate function.
 
-template <typename FromType>
-static bool CheckDateRange(const FromType & value)
-{
-    return value >= 0 && value <= DATE_LUT_MAX_DAY_NUM;
-}
-
 template <typename FromType, typename ToType>
 struct ToDateTransform32Or64
 {
     static constexpr auto name = "toDate";
 
-    static NO_SANITIZE_UNDEFINED bool IsConvertible(const FromType & from, const DateLUTImpl &)
-    {
-        return CheckDateRange(from);
-    }
-
     static NO_SANITIZE_UNDEFINED ToType execute(const FromType & from, const DateLUTImpl & time_zone)
     {
         // since converting to Date, no need in values outside of default LUT range.
@@ -395,11 +384,6 @@ struct ToDateTransform32Or64Signed
 {
     static constexpr auto name = "toDate";
 
-    static NO_SANITIZE_UNDEFINED bool IsConvertible(const FromType & from, const DateLUTImpl &)
-    {
-        return CheckDateRange(from);
-    }
-
     static NO_SANITIZE_UNDEFINED ToType execute(const FromType & from, const DateLUTImpl & time_zone)
     {
         // TODO: decide narrow or extended range based on FromType
@@ -417,11 +401,6 @@ struct ToDateTransform8Or16Signed
 {
     static constexpr auto name = "toDate";
 
-    static NO_SANITIZE_UNDEFINED bool IsConvertible(const FromType & from, const DateLUTImpl &)
-    {
-        return CheckDateRange(from);
-    }
-
     static NO_SANITIZE_UNDEFINED ToType execute(const FromType & from, const DateLUTImpl &)
     {
         if (from < 0)
@@ -518,22 +497,12 @@ template <typename Name> struct ConvertImpl<DataTypeFloat32, DataTypeDate32, Nam
 template <typename Name> struct ConvertImpl<DataTypeFloat64, DataTypeDate32, Name, ConvertDefaultBehaviorTag>
     : DateTimeTransformImpl<DataTypeFloat64, DataTypeDate32, ToDate32Transform32Or64Signed<Float64, Int32>> {};
 
-template <typename FromType>
-static bool CheckDateTimeRange(const FromType & value)
-{
-    return value >= 0 && value <= 0xFFFFFFFFL;
-}
 
 template <typename FromType, typename ToType>
 struct ToDateTimeTransform64
 {
     static constexpr auto name = "toDateTime";
 
-    static NO_SANITIZE_UNDEFINED bool IsConvertible(const FromType & from, const DateLUTImpl &)
-    {
-        return CheckDateTimeRange(from);
-    }
-
     static NO_SANITIZE_UNDEFINED ToType execute(const FromType & from, const DateLUTImpl &)
     {
         return static_cast<ToType>(std::min(time_t(from), time_t(0xFFFFFFFF)));
@@ -545,11 +514,6 @@ struct ToDateTimeTransformSigned
 {
     static constexpr auto name = "toDateTime";
 
-    static NO_SANITIZE_UNDEFINED bool IsConvertible(const FromType & from, const DateLUTImpl &)
-    {
-        return CheckDateTimeRange(from);
-    }
-
     static NO_SANITIZE_UNDEFINED ToType execute(const FromType & from, const DateLUTImpl &)
     {
         if (from < 0)
@@ -563,11 +527,6 @@ struct ToDateTimeTransform64Signed
 {
     static constexpr auto name = "toDateTime";
 
-    static NO_SANITIZE_UNDEFINED bool IsConvertible(const FromType & from, const DateLUTImpl &)
-    {
-        return CheckDateTimeRange(from);
-    }
-
     static NO_SANITIZE_UNDEFINED ToType execute(const FromType & from, const DateLUTImpl &)
     {
         if (from < 0)