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bleve/search/query/query_string_parser.go
Marty Schoch f6563ed9f5 switch from go tool yacc to goyacc as of Go 1.8
does not imply need for Go 1.8 to use, just for developers
to regenerate the query parser
2017-02-24 09:23:00 -05:00

86 lines
2.0 KiB
Go

// Copyright (c) 2014 Couchbase, 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,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// as of Go 1.8 this requires the goyacc external tool
// available from golang.org/x/tools/cmd/goyacc
//go:generate goyacc -o query_string.y.go query_string.y
//go:generate sed -i.tmp -e 1d query_string.y.go
//go:generate rm query_string.y.go.tmp
// note: OSX sed and gnu sed handle the -i (in-place) option differently.
// using -i.tmp works on both, at the expense of having to remove
// the unsightly .tmp files
package query
import (
"fmt"
"strings"
)
var debugParser bool
var debugLexer bool
func parseQuerySyntax(query string) (rq Query, err error) {
if query == "" {
return NewMatchNoneQuery(), nil
}
lex := newLexerWrapper(newQueryStringLex(strings.NewReader(query)))
doParse(lex)
if len(lex.errs) > 0 {
return nil, fmt.Errorf(strings.Join(lex.errs, "\n"))
}
return lex.query, nil
}
func doParse(lex *lexerWrapper) {
defer func() {
r := recover()
if r != nil {
lex.errs = append(lex.errs, fmt.Sprintf("parse error: %v", r))
}
}()
yyParse(lex)
}
const (
queryShould = iota
queryMust
queryMustNot
)
type lexerWrapper struct {
lex yyLexer
errs []string
query *BooleanQuery
}
func newLexerWrapper(lex yyLexer) *lexerWrapper {
return &lexerWrapper{
lex: lex,
query: NewBooleanQueryForQueryString(nil, nil, nil),
}
}
func (l *lexerWrapper) Lex(lval *yySymType) int {
return l.lex.Lex(lval)
}
func (l *lexerWrapper) Error(s string) {
l.errs = append(l.errs, s)
}