Refactor clause Writer

clause/clause.go

@@ -12,13 +12,16 @@ type ClauseBuilder interface {
 	Build(Clause, Builder)
 }
 
+type Writer interface {
+	WriteByte(byte) error
+	WriteString(string) (int, error)
+}
+
 // Builder builder interface
 type Builder interface {
-	WriteByte(byte) error
+	Writer
-	Write(sql ...string) error
 	WriteQuoted(field interface{}) error
-	AddVar(vars ...interface{}) string
+	AddVar(Writer, ...interface{})
-	Quote(field interface{}) string
 }
 
 // Clause

clause/delete.go

@@ -9,11 +9,11 @@ func (d Delete) Name() string {
 }
 
 func (d Delete) Build(builder Builder) {
-	builder.Write("DELETE")
+	builder.WriteString("DELETE")
 
 	if d.Modifier != "" {
 		builder.WriteByte(' ')
-		builder.Write(d.Modifier)
+		builder.WriteString(d.Modifier)
 	}
 }
 

clause/expression.go

@@ -1,9 +1,5 @@
 package clause
 
-import (
-	"strings"
-)
-
 // Expression expression interface
 type Expression interface {
 	Build(builder Builder)
@@ -22,11 +18,15 @@ type Expr struct {
 
 // Build build raw expression
 func (expr Expr) Build(builder Builder) {
-	sql := expr.SQL
+	var idx int
-	for _, v := range expr.Vars {
+	for _, v := range []byte(expr.SQL) {
-		sql = strings.Replace(sql, "?", builder.AddVar(v), 1)
+		if v == '?' {
+			builder.AddVar(builder, expr.Vars[idx])
+			idx++
+		} else {
+			builder.WriteByte(v)
+		}
 	}
-	builder.Write(sql)
 }
 
 // IN Whether a value is within a set of values
@@ -40,11 +40,14 @@ func (in IN) Build(builder Builder) {
 
 	switch len(in.Values) {
 	case 0:
-		builder.Write(" IN (NULL)")
+		builder.WriteString(" IN (NULL)")
 	case 1:
-		builder.Write(" = ", builder.AddVar(in.Values...))
+		builder.WriteString(" = ")
+		builder.AddVar(builder, in.Values...)
 	default:
-		builder.Write(" IN (", builder.AddVar(in.Values...), ")")
+		builder.WriteString(" IN (")
+		builder.AddVar(builder, in.Values...)
+		builder.WriteByte(')')
 	}
 }
 
@@ -52,9 +55,12 @@ func (in IN) NegationBuild(builder Builder) {
 	switch len(in.Values) {
 	case 0:
 	case 1:
-		builder.Write(" <> ", builder.AddVar(in.Values...))
+		builder.WriteString(" <> ")
+		builder.AddVar(builder, in.Values...)
 	default:
-		builder.Write(" NOT IN (", builder.AddVar(in.Values...), ")")
+		builder.WriteString(" NOT IN (")
+		builder.AddVar(builder, in.Values...)
+		builder.WriteByte(')')
 	}
 }
 
@@ -68,9 +74,10 @@ func (eq Eq) Build(builder Builder) {
 	builder.WriteQuoted(eq.Column)
 
 	if eq.Value == nil {
-		builder.Write(" IS NULL")
+		builder.WriteString(" IS NULL")
 	} else {
-		builder.Write(" = ", builder.AddVar(eq.Value))
+		builder.WriteString(" = ")
+		builder.AddVar(builder, eq.Value)
 	}
 }
 
@@ -85,9 +92,10 @@ func (neq Neq) Build(builder Builder) {
 	builder.WriteQuoted(neq.Column)
 
 	if neq.Value == nil {
-		builder.Write(" IS NOT NULL")
+		builder.WriteString(" IS NOT NULL")
 	} else {
-		builder.Write(" <> ", builder.AddVar(neq.Value))
+		builder.WriteString(" <> ")
+		builder.AddVar(builder, neq.Value)
 	}
 }
 
@@ -100,7 +108,8 @@ type Gt Eq
 
 func (gt Gt) Build(builder Builder) {
 	builder.WriteQuoted(gt.Column)
-	builder.Write(" > ", builder.AddVar(gt.Value))
+	builder.WriteString(" > ")
+	builder.AddVar(builder, gt.Value)
 }
 
 func (gt Gt) NegationBuild(builder Builder) {
@@ -112,7 +121,8 @@ type Gte Eq
 
 func (gte Gte) Build(builder Builder) {
 	builder.WriteQuoted(gte.Column)
-	builder.Write(" >= ", builder.AddVar(gte.Value))
+	builder.WriteString(" >= ")
+	builder.AddVar(builder, gte.Value)
 }
 
 func (gte Gte) NegationBuild(builder Builder) {
@@ -124,7 +134,8 @@ type Lt Eq
 
 func (lt Lt) Build(builder Builder) {
 	builder.WriteQuoted(lt.Column)
-	builder.Write(" < ", builder.AddVar(lt.Value))
+	builder.WriteString(" < ")
+	builder.AddVar(builder, lt.Value)
 }
 
 func (lt Lt) NegationBuild(builder Builder) {
@@ -136,7 +147,8 @@ type Lte Eq
 
 func (lte Lte) Build(builder Builder) {
 	builder.WriteQuoted(lte.Column)
-	builder.Write(" <= ", builder.AddVar(lte.Value))
+	builder.WriteString(" <= ")
+	builder.AddVar(builder, lte.Value)
 }
 
 func (lte Lte) NegationBuild(builder Builder) {
@@ -148,12 +160,14 @@ type Like Eq
 
 func (like Like) Build(builder Builder) {
 	builder.WriteQuoted(like.Column)
-	builder.Write(" LIKE ", builder.AddVar(like.Value))
+	builder.WriteString(" LIKE ")
+	builder.AddVar(builder, like.Value)
 }
 
 func (like Like) NegationBuild(builder Builder) {
 	builder.WriteQuoted(like.Column)
-	builder.Write(" NOT LIKE ", builder.AddVar(like.Value))
+	builder.WriteString(" NOT LIKE ")
+	builder.AddVar(builder, like.Value)
 }
 
 // Map

clause/from.go

@@ -50,18 +50,18 @@ func (from From) Build(builder Builder) {
 
 func (join Join) Build(builder Builder) {
 	if join.Type != "" {
-		builder.Write(string(join.Type))
+		builder.WriteString(string(join.Type))
 		builder.WriteByte(' ')
 	}
 
-	builder.Write("JOIN ")
+	builder.WriteString("JOIN ")
 	builder.WriteQuoted(join.Table)
 
 	if len(join.ON.Exprs) > 0 {
-		builder.Write(" ON ")
+		builder.WriteString(" ON ")
 		join.ON.Build(builder)
 	} else if len(join.Using) > 0 {
-		builder.Write(" USING (")
+		builder.WriteString(" USING (")
 		for idx, c := range join.Using {
 			if idx > 0 {
 				builder.WriteByte(',')

clause/group_by.go

@@ -22,7 +22,7 @@ func (groupBy GroupBy) Build(builder Builder) {
 	}
 
 	if len(groupBy.Having) > 0 {
-		builder.Write(" HAVING ")
+		builder.WriteString(" HAVING ")
 		Where{Exprs: groupBy.Having}.Build(builder)
 	}
 }

clause/insert.go

@@ -13,11 +13,11 @@ func (insert Insert) Name() string {
 // Build build insert clause
 func (insert Insert) Build(builder Builder) {
 	if insert.Modifier != "" {
-		builder.Write(insert.Modifier)
+		builder.WriteString(insert.Modifier)
 		builder.WriteByte(' ')
 	}
 
-	builder.Write("INTO ")
+	builder.WriteString("INTO ")
 	if insert.Table.Name == "" {
 		builder.WriteQuoted(currentTable)
 	} else {

clause/limit.go

@@ -16,12 +16,12 @@ func (limit Limit) Name() string {
 // Build build where clause
 func (limit Limit) Build(builder Builder) {
 	if limit.Limit > 0 {
-		builder.Write("LIMIT ")
+		builder.WriteString("LIMIT ")
-		builder.Write(strconv.Itoa(limit.Limit))
+		builder.WriteString(strconv.Itoa(limit.Limit))
 
 		if limit.Offset > 0 {
-			builder.Write(" OFFSET ")
+			builder.WriteString(" OFFSET ")
-			builder.Write(strconv.Itoa(limit.Offset))
+			builder.WriteString(strconv.Itoa(limit.Offset))
 		}
 	}
 }

clause/locking.go

@@ -22,16 +22,16 @@ func (f For) Build(builder Builder) {
 			builder.WriteByte(' ')
 		}
 
-		builder.Write("FOR ")
+		builder.WriteString("FOR ")
-		builder.Write(locking.Strength)
+		builder.WriteString(locking.Strength)
 		if locking.Table.Name != "" {
-			builder.Write(" OF ")
+			builder.WriteString(" OF ")
 			builder.WriteQuoted(locking.Table)
 		}
 
 		if locking.Options != "" {
 			builder.WriteByte(' ')
-			builder.Write(locking.Options)
+			builder.WriteString(locking.Options)
 		}
 	}
 }

clause/order_by.go

@@ -24,7 +24,7 @@ func (orderBy OrderBy) Build(builder Builder) {
 
 		builder.WriteQuoted(column.Column)
 		if column.Desc {
-			builder.Write(" DESC")
+			builder.WriteString(" DESC")
 		}
 	}
 }

clause/set.go

@@ -19,7 +19,7 @@ func (set Set) Build(builder Builder) {
 			}
 			builder.WriteQuoted(assignment.Column)
 			builder.WriteByte('=')
-			builder.Write(builder.AddVar(assignment.Value))
+			builder.AddVar(builder, assignment.Value)
 		}
 	} else {
 		builder.WriteQuoted(PrimaryColumn)

clause/update.go

@@ -13,7 +13,7 @@ func (update Update) Name() string {
 // Build build update clause
 func (update Update) Build(builder Builder) {
 	if update.Modifier != "" {
-		builder.Write(update.Modifier)
+		builder.WriteString(update.Modifier)
 		builder.WriteByte(' ')
 	}
 

clause/values.go

@@ -22,7 +22,7 @@ func (values Values) Build(builder Builder) {
 		}
 		builder.WriteByte(')')
 
-		builder.Write(" VALUES ")
+		builder.WriteString(" VALUES ")
 
 		for idx, value := range values.Values {
 			if idx > 0 {
@@ -30,11 +30,11 @@ func (values Values) Build(builder Builder) {
 			}
 
 			builder.WriteByte('(')
-			builder.Write(builder.AddVar(value...))
+			builder.AddVar(builder, value...)
 			builder.WriteByte(')')
 		}
 	} else {
-		builder.Write("DEFAULT VALUES")
+		builder.WriteString("DEFAULT VALUES")
 	}
 }
 

clause/where.go

@@ -26,9 +26,9 @@ func (where Where) Build(builder Builder) {
 		if expr != nil {
 			if idx > 0 {
 				if v, ok := expr.(OrConditions); ok && len(v.Exprs) == 1 {
-					builder.Write(" OR ")
+					builder.WriteString(" OR ")
 				} else {
-					builder.Write(" AND ")
+					builder.WriteString(" AND ")
 				}
 			}
 
@@ -65,7 +65,7 @@ func (and AndConditions) Build(builder Builder) {
 	}
 	for idx, c := range and.Exprs {
 		if idx > 0 {
-			builder.Write(" AND ")
+			builder.WriteString(" AND ")
 		}
 		c.Build(builder)
 	}
@@ -91,7 +91,7 @@ func (or OrConditions) Build(builder Builder) {
 	}
 	for idx, c := range or.Exprs {
 		if idx > 0 {
-			builder.Write(" OR ")
+			builder.WriteString(" OR ")
 		}
 		c.Build(builder)
 	}
@@ -117,13 +117,13 @@ func (not NotConditions) Build(builder Builder) {
 	}
 	for idx, c := range not.Exprs {
 		if idx > 0 {
-			builder.Write(" AND ")
+			builder.WriteString(" AND ")
 		}
 
 		if negationBuilder, ok := c.(NegationExpressionBuilder); ok {
 			negationBuilder.NegationBuild(builder)
 		} else {
-			builder.Write(" NOT ")
+			builder.WriteString(" NOT ")
 			c.Build(builder)
 		}
 	}

dialects/mssql/mssql.go

@@ -5,11 +5,11 @@ import (
 	"fmt"
 	"regexp"
 	"strconv"
-	"strings"
 
 	_ "github.com/denisenkom/go-mssqldb"
 	"github.com/jinzhu/gorm"
 	"github.com/jinzhu/gorm/callbacks"
+	"github.com/jinzhu/gorm/clause"
 	"github.com/jinzhu/gorm/logger"
 	"github.com/jinzhu/gorm/migrator"
 	"github.com/jinzhu/gorm/schema"
@@ -42,10 +42,10 @@ func (dialector Dialector) BindVar(stmt *gorm.Statement, v interface{}) string {
 	return "@p" + strconv.Itoa(len(stmt.Vars))
 }
 
-func (dialector Dialector) QuoteTo(builder *strings.Builder, str string) {
+func (dialector Dialector) QuoteTo(writer clause.Writer, str string) {
-	builder.WriteByte('"')
+	writer.WriteByte('"')
-	builder.WriteString(str)
+	writer.WriteString(str)
-	builder.WriteByte('"')
+	writer.WriteByte('"')
 }
 
 var numericPlaceholder = regexp.MustCompile("@p(\\d+)")

dialects/mysql/mysql.go

@@ -4,11 +4,11 @@ import (
 	"database/sql"
 	"fmt"
 	"math"
-	"strings"
 
 	_ "github.com/go-sql-driver/mysql"
 	"github.com/jinzhu/gorm"
 	"github.com/jinzhu/gorm/callbacks"
+	"github.com/jinzhu/gorm/clause"
 	"github.com/jinzhu/gorm/logger"
 	"github.com/jinzhu/gorm/migrator"
 	"github.com/jinzhu/gorm/schema"
@@ -40,10 +40,10 @@ func (dialector Dialector) BindVar(stmt *gorm.Statement, v interface{}) string {
 	return "?"
 }
 
-func (dialector Dialector) QuoteTo(builder *strings.Builder, str string) {
+func (dialector Dialector) QuoteTo(writer clause.Writer, str string) {
-	builder.WriteByte('`')
+	writer.WriteByte('`')
-	builder.WriteString(str)
+	writer.WriteString(str)
-	builder.WriteByte('`')
+	writer.WriteByte('`')
 }
 
 func (dialector Dialector) Explain(sql string, vars ...interface{}) string {

dialects/postgres/postgres.go

@@ -5,10 +5,10 @@ import (
 	"fmt"
 	"regexp"
 	"strconv"
-	"strings"
 
 	"github.com/jinzhu/gorm"
 	"github.com/jinzhu/gorm/callbacks"
+	"github.com/jinzhu/gorm/clause"
 	"github.com/jinzhu/gorm/logger"
 	"github.com/jinzhu/gorm/migrator"
 	"github.com/jinzhu/gorm/schema"
@@ -42,10 +42,10 @@ func (dialector Dialector) BindVar(stmt *gorm.Statement, v interface{}) string {
 	return "$" + strconv.Itoa(len(stmt.Vars))
 }
 
-func (dialector Dialector) QuoteTo(builder *strings.Builder, str string) {
+func (dialector Dialector) QuoteTo(writer clause.Writer, str string) {
-	builder.WriteByte('"')
+	writer.WriteByte('"')
-	builder.WriteString(str)
+	writer.WriteString(str)
-	builder.WriteByte('"')
+	writer.WriteByte('"')
 }
 
 var numericPlaceholder = regexp.MustCompile("\\$(\\d+)")

dialects/sqlite/sqlite.go

@@ -2,10 +2,10 @@ package sqlite
 
 import (
 	"database/sql"
-	"strings"
 
 	"github.com/jinzhu/gorm"
 	"github.com/jinzhu/gorm/callbacks"
+	"github.com/jinzhu/gorm/clause"
 	"github.com/jinzhu/gorm/logger"
 	"github.com/jinzhu/gorm/migrator"
 	"github.com/jinzhu/gorm/schema"
@@ -39,10 +39,10 @@ func (dialector Dialector) BindVar(stmt *gorm.Statement, v interface{}) string {
 	return "?"
 }
 
-func (dialector Dialector) QuoteTo(builder *strings.Builder, str string) {
+func (dialector Dialector) QuoteTo(writer clause.Writer, str string) {
-	builder.WriteByte('`')
+	writer.WriteByte('`')
-	builder.WriteString(str)
+	writer.WriteString(str)
-	builder.WriteByte('`')
+	writer.WriteByte('`')
 }
 
 func (dialector Dialector) Explain(sql string, vars ...interface{}) string {

interfaces.go

@@ -3,8 +3,8 @@ package gorm
 import (
 	"context"
 	"database/sql"
-	"strings"
 
+	"github.com/jinzhu/gorm/clause"
 	"github.com/jinzhu/gorm/schema"
 )
 
@@ -14,7 +14,7 @@ type Dialector interface {
 	Migrator(db *DB) Migrator
 	DataTypeOf(*schema.Field) string
 	BindVar(stmt *Statement, v interface{}) string
-	QuoteTo(*strings.Builder, string)
+	QuoteTo(clause.Writer, string)
 	Explain(sql string, vars ...interface{}) string
 }
 

statement.go

@@ -34,7 +34,6 @@ type Statement struct {
 	SQL                  strings.Builder
 	Vars                 []interface{}
 	NamedVars            []sql.NamedArg
-	placeholders         strings.Builder
 }
 
 // StatementOptimizer statement optimizer interface
@@ -43,15 +42,12 @@ type StatementOptimizer interface {
 }
 
 // Write write string
-func (stmt *Statement) Write(sql ...string) (err error) {
+func (stmt *Statement) WriteString(str string) (int, error) {
-	for _, s := range sql {
+	return stmt.SQL.WriteString(str)
-		_, err = stmt.SQL.WriteString(s)
-	}
-	return
 }
 
 // Write write string
-func (stmt *Statement) WriteByte(c byte) (err error) {
+func (stmt *Statement) WriteByte(c byte) error {
 	return stmt.SQL.WriteByte(c)
 }
 
@@ -62,7 +58,7 @@ func (stmt *Statement) WriteQuoted(value interface{}) error {
 }
 
 // QuoteTo write quoted value to writer
-func (stmt Statement) QuoteTo(writer *strings.Builder, field interface{}) {
+func (stmt Statement) QuoteTo(writer clause.Writer, field interface{}) {
 	switch v := field.(type) {
 	case clause.Table:
 		if v.Name == clause.CurrentTable {
@@ -110,44 +106,41 @@ func (stmt Statement) Quote(field interface{}) string {
 }
 
 // Write write string
-func (stmt *Statement) AddVar(vars ...interface{}) string {
+func (stmt *Statement) AddVar(writer clause.Writer, vars ...interface{}) {
-	stmt.placeholders = strings.Builder{}
-	stmt.placeholders.Reset()
-
 	for idx, v := range vars {
 		if idx > 0 {
-			stmt.placeholders.WriteByte(',')
+			writer.WriteByte(',')
 		}
 
 		switch v := v.(type) {
 		case sql.NamedArg:
 			if len(v.Name) > 0 {
 				stmt.NamedVars = append(stmt.NamedVars, v)
-				stmt.placeholders.WriteByte('@')
+				writer.WriteByte('@')
-				stmt.placeholders.WriteString(v.Name)
+				writer.WriteString(v.Name)
 			} else {
 				stmt.Vars = append(stmt.Vars, v.Value)
-				stmt.placeholders.WriteString(stmt.DB.Dialector.BindVar(stmt, v.Value))
+				writer.WriteString(stmt.DB.Dialector.BindVar(stmt, v.Value))
 			}
 		case clause.Column, clause.Table:
-			stmt.placeholders.WriteString(stmt.Quote(v))
+			stmt.QuoteTo(writer, v)
 		case clause.Expr:
-			stmt.placeholders.WriteString(v.SQL)
+			writer.WriteString(v.SQL)
 			stmt.Vars = append(stmt.Vars, v.Vars...)
 		case []interface{}:
 			if len(v) > 0 {
-				stmt.placeholders.WriteByte('(')
+				writer.WriteByte('(')
-				stmt.placeholders.WriteString(stmt.AddVar(v...))
+				stmt.skipResetPlacehodler = true
-				stmt.placeholders.WriteByte(')')
+				stmt.AddVar(writer, v...)
+				writer.WriteByte(')')
 			} else {
-				stmt.placeholders.WriteString("(NULL)")
+				writer.WriteString("(NULL)")
 			}
 		default:
 			stmt.Vars = append(stmt.Vars, v)
-			stmt.placeholders.WriteString(stmt.DB.Dialector.BindVar(stmt, v))
+			writer.WriteString(stmt.DB.Dialector.BindVar(stmt, v))
 		}
 	}
-	return stmt.placeholders.String()
 }
 
 // AddClause add clause

tests/dummy_dialecter.go

@@ -1,9 +1,8 @@
 package tests
 
 import (
-	"strings"
-
 	"github.com/jinzhu/gorm"
+	"github.com/jinzhu/gorm/clause"
 	"github.com/jinzhu/gorm/logger"
 	"github.com/jinzhu/gorm/schema"
 )
@@ -23,10 +22,10 @@ func (DummyDialector) BindVar(stmt *gorm.Statement, v interface{}) string {
 	return "?"
 }
 
-func (DummyDialector) QuoteTo(builder *strings.Builder, str string) {
+func (DummyDialector) QuoteTo(writer clause.Writer, str string) {
-	builder.WriteByte('`')
+	writer.WriteByte('`')
-	builder.WriteString(str)
+	writer.WriteString(str)
-	builder.WriteByte('`')
+	writer.WriteByte('`')
 }
 
 func (DummyDialector) Explain(sql string, vars ...interface{}) string {