Adding upstream version 2.5.1.

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

analysis/lang/pl/stempel/strenum.go

@@ -0,0 +1,48 @@
+//  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 (
+	"io"
+)
+
+type strEnum struct {
+	r    []rune
+	from int
+	by   int
+}
+
+func newStrEnum(s []rune, up bool) *strEnum {
+	rv := &strEnum{
+		r: s,
+	}
+	if up {
+		rv.from = 0
+		rv.by = 1
+	} else {
+		rv.from = len(s) - 1
+		rv.by = -1
+	}
+	return rv
+}
+
+func (s *strEnum) next() (rune, error) {
+	if s.from < 0 || s.from >= len(s.r) {
+		return 0, io.EOF
+	}
+	rv := s.r[s.from]
+	s.from += s.by
+	return rv, nil
+}