forgejo-federation/vendor/github.com/pingcap/tidb/ast/stringer.go

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// Copyright 2015 PingCAP, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// See the License for the specific language governing permissions and
// limitations under the License.
package ast
import (
"fmt"
"github.com/pingcap/tidb/util/types"
)
// ToString converts a node to a string for debugging purpose.
func ToString(node Node) string {
s := &stringer{strMap: map[Node]string{}}
node.Accept(s)
return s.strMap[node]
}
type stringer struct {
strMap map[Node]string
}
// Enter implements Visitor Enter interface.
func (c *stringer) Enter(node Node) (Node, bool) {
return node, false
}
// Leave implements Visitor Leave interface.
func (c *stringer) Leave(in Node) (out Node, ok bool) {
switch x := in.(type) {
case *BinaryOperationExpr:
left := c.strMap[x.L]
right := c.strMap[x.R]
c.strMap[x] = left + " " + x.Op.String() + " " + right
case *ValueExpr:
str, _ := types.ToString(x.GetValue())
c.strMap[x] = str
case *ParenthesesExpr:
c.strMap[x] = "(" + c.strMap[x.Expr] + ")"
case *ColumnNameExpr:
c.strMap[x] = x.Name.Table.O + "." + x.Name.Name.O
case *BetweenExpr:
c.strMap[x] = c.strMap[x.Expr] + " BETWWEN " + c.strMap[x.Left] + " AND " + c.strMap[x.Right]
default:
c.strMap[in] = fmt.Sprintf("%T", in)
}
return in, true
}