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-rw-r--r--vendor/golang.org/x/text/encoding/unicode/override.go82
1 files changed, 0 insertions, 82 deletions
diff --git a/vendor/golang.org/x/text/encoding/unicode/override.go b/vendor/golang.org/x/text/encoding/unicode/override.go
deleted file mode 100644
index 35d62fc..0000000
--- a/vendor/golang.org/x/text/encoding/unicode/override.go
+++ /dev/null
@@ -1,82 +0,0 @@
-// 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 unicode
-
-import (
- "golang.org/x/text/transform"
-)
-
-// BOMOverride returns a new decoder transformer that is identical to fallback,
-// except that the presence of a Byte Order Mark at the start of the input
-// causes it to switch to the corresponding Unicode decoding. It will only
-// consider BOMs for UTF-8, UTF-16BE, and UTF-16LE.
-//
-// This differs from using ExpectBOM by allowing a BOM to switch to UTF-8, not
-// just UTF-16 variants, and allowing falling back to any encoding scheme.
-//
-// This technique is recommended by the W3C for use in HTML 5: "For
-// compatibility with deployed content, the byte order mark (also known as BOM)
-// is considered more authoritative than anything else."
-// http://www.w3.org/TR/encoding/#specification-hooks
-//
-// Using BOMOverride is mostly intended for use cases where the first characters
-// of a fallback encoding are known to not be a BOM, for example, for valid HTML
-// and most encodings.
-func BOMOverride(fallback transform.Transformer) transform.Transformer {
- // TODO: possibly allow a variadic argument of unicode encodings to allow
- // specifying details of which fallbacks are supported as well as
- // specifying the details of the implementations. This would also allow for
- // support for UTF-32, which should not be supported by default.
- return &bomOverride{fallback: fallback}
-}
-
-type bomOverride struct {
- fallback transform.Transformer
- current transform.Transformer
-}
-
-func (d *bomOverride) Reset() {
- d.current = nil
- d.fallback.Reset()
-}
-
-var (
- // TODO: we could use decode functions here, instead of allocating a new
- // decoder on every NewDecoder as IgnoreBOM decoders can be stateless.
- utf16le = UTF16(LittleEndian, IgnoreBOM)
- utf16be = UTF16(BigEndian, IgnoreBOM)
-)
-
-const utf8BOM = "\ufeff"
-
-func (d *bomOverride) Transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error) {
- if d.current != nil {
- return d.current.Transform(dst, src, atEOF)
- }
- if len(src) < 3 && !atEOF {
- return 0, 0, transform.ErrShortSrc
- }
- d.current = d.fallback
- bomSize := 0
- if len(src) >= 2 {
- if src[0] == 0xFF && src[1] == 0xFE {
- d.current = utf16le.NewDecoder()
- bomSize = 2
- } else if src[0] == 0xFE && src[1] == 0xFF {
- d.current = utf16be.NewDecoder()
- bomSize = 2
- } else if len(src) >= 3 &&
- src[0] == utf8BOM[0] &&
- src[1] == utf8BOM[1] &&
- src[2] == utf8BOM[2] {
- d.current = transform.Nop
- bomSize = 3
- }
- }
- if bomSize < len(src) {
- nDst, nSrc, err = d.current.Transform(dst, src[bomSize:], atEOF)
- }
- return nDst, nSrc + bomSize, err
-}