Adding upstream version 2.5.1.

Signed-off-by: Daniel Baumann <daniel@debian.org>

search/query/prefix.go

@@ -0,0 +1,64 @@
+//  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.
+
+package query
+
+import (
+	"context"
+
+	"github.com/blevesearch/bleve/v2/mapping"
+	"github.com/blevesearch/bleve/v2/search"
+	"github.com/blevesearch/bleve/v2/search/searcher"
+	index "github.com/blevesearch/bleve_index_api"
+)
+
+type PrefixQuery struct {
+	Prefix   string `json:"prefix"`
+	FieldVal string `json:"field,omitempty"`
+	BoostVal *Boost `json:"boost,omitempty"`
+}
+
+// NewPrefixQuery creates a new Query which finds
+// documents containing terms that start with the
+// specified prefix.
+func NewPrefixQuery(prefix string) *PrefixQuery {
+	return &PrefixQuery{
+		Prefix: prefix,
+	}
+}
+
+func (q *PrefixQuery) SetBoost(b float64) {
+	boost := Boost(b)
+	q.BoostVal = &boost
+}
+
+func (q *PrefixQuery) Boost() float64 {
+	return q.BoostVal.Value()
+}
+
+func (q *PrefixQuery) SetField(f string) {
+	q.FieldVal = f
+}
+
+func (q *PrefixQuery) Field() string {
+	return q.FieldVal
+}
+
+func (q *PrefixQuery) Searcher(ctx context.Context, i index.IndexReader, m mapping.IndexMapping, options search.SearcherOptions) (search.Searcher, error) {
+	field := q.FieldVal
+	if q.FieldVal == "" {
+		field = m.DefaultSearchField()
+	}
+	return searcher.NewTermPrefixSearcher(ctx, i, q.Prefix, field, q.BoostVal.Value(), options)
+}