Adding upstream version 2.5.1.

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

analysis/token/camelcase/parser.go

@@ -0,0 +1,109 @@
+//  Copyright (c) 2016 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 camelcase
+
+import (
+	"github.com/blevesearch/bleve/v2/analysis"
+)
+
+func (p *Parser) buildTokenFromTerm(buffer []rune) *analysis.Token {
+	term := analysis.BuildTermFromRunes(buffer)
+	token := &analysis.Token{
+		Term:     term,
+		Position: p.position,
+		Start:    p.index,
+		End:      p.index + len(term),
+	}
+	p.position++
+	p.index += len(term)
+	return token
+}
+
+// Parser accepts a symbol and passes it to the current state (representing a class).
+// The state can accept it (and accumulate it). Otherwise, the parser creates a new state that
+// starts with the pushed symbol.
+//
+// Parser accumulates a new resulting token every time it switches state.
+// Use FlushTokens() to get the results after the last symbol was pushed.
+type Parser struct {
+	bufferLen int
+	buffer    []rune
+	current   State
+	tokens    []*analysis.Token
+	position  int
+	index     int
+}
+
+func NewParser(length, position, index int) *Parser {
+	return &Parser{
+		bufferLen: length,
+		buffer:    make([]rune, 0, length),
+		tokens:    make([]*analysis.Token, 0, length),
+		position:  position,
+		index:     index,
+	}
+}
+
+func (p *Parser) Push(sym rune, peek *rune) {
+	if p.current == nil {
+		// the start of parsing
+		p.current = p.NewState(sym)
+		p.buffer = append(p.buffer, sym)
+
+	} else if p.current.Member(sym, peek) {
+		// same state, just accumulate
+		p.buffer = append(p.buffer, sym)
+
+	} else {
+		// the old state is no more, thus convert the buffer
+		p.tokens = append(p.tokens, p.buildTokenFromTerm(p.buffer))
+
+		// let the new state begin
+		p.current = p.NewState(sym)
+		p.buffer = make([]rune, 0, p.bufferLen)
+		p.buffer = append(p.buffer, sym)
+	}
+}
+
+// Note. States have to have different starting symbols.
+func (p *Parser) NewState(sym rune) State {
+	var found State
+
+	found = &LowerCaseState{}
+	if found.StartSym(sym) {
+		return found
+	}
+
+	found = &UpperCaseState{}
+	if found.StartSym(sym) {
+		return found
+	}
+
+	found = &NumberCaseState{}
+	if found.StartSym(sym) {
+		return found
+	}
+
+	return &NonAlphaNumericCaseState{}
+}
+
+func (p *Parser) FlushTokens() []*analysis.Token {
+	p.tokens = append(p.tokens, p.buildTokenFromTerm(p.buffer))
+	return p.tokens
+}
+
+func (p *Parser) NextPosition() int {
+	return p.position
+}