Adding upstream version 2.5.1.

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

analysis/tokenizer/regexp/regexp.go

@@ -0,0 +1,87 @@
+//  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 regexp
+
+import (
+	"fmt"
+	"regexp"
+	"strconv"
+
+	"github.com/blevesearch/bleve/v2/analysis"
+	"github.com/blevesearch/bleve/v2/registry"
+)
+
+const Name = "regexp"
+
+var IdeographRegexp = regexp.MustCompile(`\p{Han}|\p{Hangul}|\p{Hiragana}|\p{Katakana}`)
+
+type RegexpTokenizer struct {
+	r *regexp.Regexp
+}
+
+func NewRegexpTokenizer(r *regexp.Regexp) *RegexpTokenizer {
+	return &RegexpTokenizer{
+		r: r,
+	}
+}
+
+func (rt *RegexpTokenizer) Tokenize(input []byte) analysis.TokenStream {
+	matches := rt.r.FindAllIndex(input, -1)
+	rv := make(analysis.TokenStream, 0, len(matches))
+	for i, match := range matches {
+		matchBytes := input[match[0]:match[1]]
+		if match[1]-match[0] > 0 {
+			token := analysis.Token{
+				Term:     matchBytes,
+				Start:    match[0],
+				End:      match[1],
+				Position: i + 1,
+				Type:     detectTokenType(matchBytes),
+			}
+			rv = append(rv, &token)
+		}
+	}
+	return rv
+}
+
+func RegexpTokenizerConstructor(config map[string]interface{}, cache *registry.Cache) (analysis.Tokenizer, error) {
+	rval, ok := config["regexp"].(string)
+	if !ok {
+		return nil, fmt.Errorf("must specify regexp")
+	}
+	r, err := regexp.Compile(rval)
+	if err != nil {
+		return nil, fmt.Errorf("unable to build regexp tokenizer: %v", err)
+	}
+	return NewRegexpTokenizer(r), nil
+}
+
+func init() {
+	err := registry.RegisterTokenizer(Name, RegexpTokenizerConstructor)
+	if err != nil {
+		panic(err)
+	}
+}
+
+func detectTokenType(termBytes []byte) analysis.TokenType {
+	if IdeographRegexp.Match(termBytes) {
+		return analysis.Ideographic
+	}
+	_, err := strconv.ParseFloat(string(termBytes), 64)
+	if err == nil {
+		return analysis.Numeric
+	}
+	return analysis.AlphaNumeric
+}