diff options
Diffstat (limited to 'vendor/golang.org/x/text/secure/precis/nickname.go')
-rw-r--r-- | vendor/golang.org/x/text/secure/precis/nickname.go | 72 |
1 files changed, 72 insertions, 0 deletions
diff --git a/vendor/golang.org/x/text/secure/precis/nickname.go b/vendor/golang.org/x/text/secure/precis/nickname.go new file mode 100644 index 0000000..11e0ccb --- /dev/null +++ b/vendor/golang.org/x/text/secure/precis/nickname.go @@ -0,0 +1,72 @@ +// Copyright 2015 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package precis + +import ( + "unicode" + "unicode/utf8" + + "golang.org/x/text/transform" +) + +type nickAdditionalMapping struct { + // TODO: This transformer needs to be stateless somehow… + notStart bool + prevSpace bool +} + +func (t *nickAdditionalMapping) Reset() { + t.prevSpace = false + t.notStart = false +} + +func (t *nickAdditionalMapping) Transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error) { + // RFC 8266 §2.1. Rules + // + // 2. Additional Mapping Rule: The additional mapping rule consists of + // the following sub-rules. + // + // a. Map any instances of non-ASCII space to SPACE (U+0020); a + // non-ASCII space is any Unicode code point having a general + // category of "Zs", naturally with the exception of SPACE + // (U+0020). (The inclusion of only ASCII space prevents + // confusion with various non-ASCII space code points, many of + // which are difficult to reproduce across different input + // methods.) + // + // b. Remove any instances of the ASCII space character at the + // beginning or end of a nickname (e.g., "stpeter " is mapped to + // "stpeter"). + // + // c. Map interior sequences of more than one ASCII space character + // to a single ASCII space character (e.g., "St Peter" is + // mapped to "St Peter"). + for nSrc < len(src) { + r, size := utf8.DecodeRune(src[nSrc:]) + if size == 0 { // Incomplete UTF-8 encoding + if !atEOF { + return nDst, nSrc, transform.ErrShortSrc + } + size = 1 + } + if unicode.Is(unicode.Zs, r) { + t.prevSpace = true + } else { + if t.prevSpace && t.notStart { + dst[nDst] = ' ' + nDst += 1 + } + if size != copy(dst[nDst:], src[nSrc:nSrc+size]) { + nDst += size + return nDst, nSrc, transform.ErrShortDst + } + nDst += size + t.prevSpace = false + t.notStart = true + } + nSrc += size + } + return nDst, nSrc, nil +} |