From dae3e8a69b1a4ef82ea9d5f68551bd00cc4e7322 Mon Sep 17 00:00:00 2001
From: ZhaoQian888 <1900022850@pku.edu.cn>
Date: Wed, 18 Dec 2019 21:51:36 +0800
Subject: [PATCH] add func

---
 expression/builtin_math.go     | 18 ++++++-----
 expression/builtin_math_vec.go | 59 +++-------------------------------
 2 files changed, 14 insertions(+), 63 deletions(-)

diff --git a/expression/builtin_math.go b/expression/builtin_math.go
index 59baf23e048c0..9d0e39cc9ac55 100644
--- a/expression/builtin_math.go
+++ b/expression/builtin_math.go
@@ -1125,7 +1125,7 @@ func (b *builtinConvSig) Clone() builtinFunc {
 // evalString evals CONV(N,from_base,to_base).
 // See https://dev.mysql.com/doc/refman/5.7/en/mathematical-functions.html#function_conv.
 func (b *builtinConvSig) evalString(row chunk.Row) (res string, isNull bool, err error) {
-	n, isNull, err := b.args[0].EvalString(b.ctx, row)
+	str, isNull, err := b.args[0].EvalString(b.ctx, row)
 	if isNull || err != nil {
 		return res, isNull, err
 	}
@@ -1139,7 +1139,9 @@ func (b *builtinConvSig) evalString(row chunk.Row) (res string, isNull bool, err
 	if isNull || err != nil {
 		return res, isNull, err
 	}
-
+	return b.conv(str, fromBase, toBase)
+}
+func (b *builtinConvSig) conv(str string, fromBase, toBase int64) (res string, isNull bool, err error) {
 	var (
 		signed     bool
 		negative   bool
@@ -1159,19 +1161,19 @@ func (b *builtinConvSig) evalString(row chunk.Row) (res string, isNull bool, err
 		return res, true, nil
 	}
 
-	n = getValidPrefix(strings.TrimSpace(n), fromBase)
-	if len(n) == 0 {
+	str = getValidPrefix(strings.TrimSpace(str), fromBase)
+	if len(str) == 0 {
 		return "0", false, nil
 	}
 
-	if n[0] == '-' {
+	if str[0] == '-' {
 		negative = true
-		n = n[1:]
+		str = str[1:]
 	}
 
-	val, err := strconv.ParseUint(n, int(fromBase), 64)
+	val, err := strconv.ParseUint(str, int(fromBase), 64)
 	if err != nil {
-		return res, false, types.ErrOverflow.GenWithStackByArgs("BIGINT UNSINGED", n)
+		return res, false, types.ErrOverflow.GenWithStackByArgs("BIGINT UNSINGED", str)
 	}
 	if signed {
 		if negative && val > -math.MinInt64 {
diff --git a/expression/builtin_math_vec.go b/expression/builtin_math_vec.go
index b5e8d7914e1d3..5628b89bde10c 100644
--- a/expression/builtin_math_vec.go
+++ b/expression/builtin_math_vec.go
@@ -19,7 +19,6 @@ import (
 	"math"
 	"math/rand"
 	"strconv"
-	"strings"
 	"time"
 
 	"github.com/cznic/mathutil"
@@ -1081,69 +1080,19 @@ func (b *builtinConvSig) vecEvalString(input *chunk.Chunk, result *chunk.Column)
 	result.ReserveString(n)
 	fromBase := buf2.Int64s()
 	toBase := buf3.Int64s()
-	var (
-		signed     bool
-		negative   bool
-		ignoreSign bool
-	)
 	for i := 0; i < n; i++ {
 		if buf1.IsNull(i) || buf2.IsNull(i) || buf3.IsNull(i) {
 			result.AppendNull()
 			continue
 		}
-		signed = false
-		negative = false
-		ignoreSign = false
-		if fromBase[i] < 0 {
-			fromBase[i] = -fromBase[i]
-			signed = true
-		}
-		if toBase[i] < 0 {
-			toBase[i] = -toBase[i]
-			ignoreSign = true
+		res, isNull, err := b.conv(buf1.GetString(i), fromBase[i], toBase[i])
+		if err != nil {
+			return err
 		}
-		if fromBase[i] > 36 || fromBase[i] < 2 || toBase[i] > 36 || toBase[i] < 2 {
+		if isNull {
 			result.AppendNull()
 			continue
 		}
-		n := getValidPrefix(strings.TrimSpace(buf1.GetString(i)), fromBase[i])
-		if len(n) == 0 {
-			result.AppendString("0")
-			continue
-		}
-		if n[0] == '-' {
-			negative = true
-			n = n[1:]
-		}
-		val, err := strconv.ParseUint(n, int(fromBase[i]), 64)
-		if err != nil {
-			result.AppendNull()
-			return types.ErrOverflow.GenWithStackByArgs("BIGINT UNSINGED", n)
-		}
-		if signed {
-			if negative && val > -math.MinInt64 {
-				val = -math.MinInt64
-			}
-			if !negative && val > math.MaxInt64 {
-				val = math.MaxInt64
-			}
-		}
-		if negative {
-			val = -val
-		}
-		if int64(val) < 0 {
-			negative = true
-		} else {
-			negative = false
-		}
-		if ignoreSign && negative {
-			val = 0 - val
-		}
-		s := strconv.FormatUint(val, int(toBase[i]))
-		if negative && ignoreSign {
-			s = "-" + s
-		}
-		res := strings.ToUpper(s)
 		result.AppendString(res)
 	}
 	return nil