1// Copyright 2016 The Go Authors. All rights reserved.
 2// Use of this source code is governed by a BSD-style
 3// license that can be found in the LICENSE file.
 4
 5package cases
 6
 7import "golang.org/x/text/transform"
 8
 9type caseFolder struct{ transform.NopResetter }
10
11// caseFolder implements the Transformer interface for doing case folding.
12func (t *caseFolder) Transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error) {
13	c := context{dst: dst, src: src, atEOF: atEOF}
14	for c.next() {
15		foldFull(&c)
16		c.checkpoint()
17	}
18	return c.ret()
19}
20
21func (t *caseFolder) Span(src []byte, atEOF bool) (n int, err error) {
22	c := context{src: src, atEOF: atEOF}
23	for c.next() && isFoldFull(&c) {
24		c.checkpoint()
25	}
26	return c.retSpan()
27}
28
29func makeFold(o options) transform.SpanningTransformer {
30	// TODO: Special case folding, through option Language, Special/Turkic, or
31	// both.
32	// TODO: Implement Compact options.
33	return &caseFolder{}
34}