Adding upstream version 2.5.1.

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

analysis/lang/pl/stempel/trie.go

@@ -0,0 +1,132 @@
+//  Copyright (c) 2018 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 stempel
+
+import (
+	"fmt"
+
+	"github.com/blevesearch/stempel/javadata"
+)
+
+// trie represents the internal trie structure
+type trie struct {
+	rows    []*row
+	cmds    []string
+	root    int32
+	forward bool
+}
+
+func newTrie(r *javadata.Reader) (rv *trie, err error) {
+	rv = &trie{}
+	rv.forward, err = r.ReadBool()
+	if err != nil {
+		return nil, fmt.Errorf("error reading trie forward: %v", err)
+	}
+	rv.root, err = r.ReadInt32()
+	if err != nil {
+		return nil, fmt.Errorf("error reading trie root: %v", err)
+	}
+
+	// commands
+	nCommands, err := r.ReadInt32()
+	if err != nil {
+		return nil, fmt.Errorf("error reading trie num commands: %v", err)
+	}
+	for nCommands > 0 {
+		utfCommand, nerr := r.ReadUTF()
+		if nerr != nil {
+			return nil, fmt.Errorf("error reading trie command utf: %v", nerr)
+		}
+		rv.cmds = append(rv.cmds, utfCommand)
+		nCommands--
+	}
+
+	// rows
+	nRows, err := r.ReadInt32()
+	if err != nil {
+		return nil, fmt.Errorf("error reading trie num rows: %v", err)
+	}
+	for nRows > 0 {
+		row, err := newRow(r)
+		if err != nil {
+			return nil, fmt.Errorf("error reading trie row: %v", err)
+		}
+		rv.rows = append(rv.rows, row)
+		nRows--
+	}
+
+	return rv, nil
+}
+
+func (t *trie) getRow(i int) *row {
+	if i < 0 || i >= len(t.rows) {
+		return nil
+	}
+	return t.rows[i]
+}
+
+func (t *trie) GetLastOnPath(key []rune) []rune {
+	now := t.getRow(int(t.root))
+	var last []rune
+	var w int32
+	e := newStrEnum(key, t.forward)
+
+	// walk over each rune
+	// if rune has row in the table, note the cmd (as last)
+	// if rune has row in table, see if it transitions to another row
+	// if it does, move to that row and next char on next loop itr
+	// if it does not, return the last cmd
+	// if you get to end of string and there is command in row use it
+	// or return last
+	for i := 0; i < len(key)-1; i++ {
+		r, err := e.next()
+		if err != nil {
+			return last
+		}
+		w = now.getCmd(r)
+		if w >= 0 {
+			last = []rune(t.cmds[w])
+		}
+		w = now.getRef(r)
+		if w >= 0 {
+			now = t.getRow(int(w))
+		} else {
+			return last
+		}
+	}
+	r, err := e.next()
+	if err != nil {
+		return last
+	}
+	w = now.getCmd(r)
+	if err != nil {
+		return last
+	}
+	if w >= 0 {
+		return []rune(t.cmds[w])
+	}
+	return last
+}
+
+func (t *trie) String() string {
+	rv := ""
+	for _, cmd := range t.cmds {
+		rv += fmt.Sprintf("cmd: %s\n", string(cmd))
+	}
+	for _, row := range t.rows {
+		rv += fmt.Sprintf("row: %v\n", row)
+	}
+	return rv
+}