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-rw-r--r--vendor/gopkg.in/mgo.v2/internal/json/fold.go143
1 files changed, 0 insertions, 143 deletions
diff --git a/vendor/gopkg.in/mgo.v2/internal/json/fold.go b/vendor/gopkg.in/mgo.v2/internal/json/fold.go
deleted file mode 100644
index 9e17012..0000000
--- a/vendor/gopkg.in/mgo.v2/internal/json/fold.go
+++ /dev/null
@@ -1,143 +0,0 @@
-// Copyright 2013 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 json
-
-import (
- "bytes"
- "unicode/utf8"
-)
-
-const (
- caseMask = ^byte(0x20) // Mask to ignore case in ASCII.
- kelvin = '\u212a'
- smallLongEss = '\u017f'
-)
-
-// foldFunc returns one of four different case folding equivalence
-// functions, from most general (and slow) to fastest:
-//
-// 1) bytes.EqualFold, if the key s contains any non-ASCII UTF-8
-// 2) equalFoldRight, if s contains special folding ASCII ('k', 'K', 's', 'S')
-// 3) asciiEqualFold, no special, but includes non-letters (including _)
-// 4) simpleLetterEqualFold, no specials, no non-letters.
-//
-// The letters S and K are special because they map to 3 runes, not just 2:
-// * S maps to s and to U+017F 'ſ' Latin small letter long s
-// * k maps to K and to U+212A 'K' Kelvin sign
-// See https://play.golang.org/p/tTxjOc0OGo
-//
-// The returned function is specialized for matching against s and
-// should only be given s. It's not curried for performance reasons.
-func foldFunc(s []byte) func(s, t []byte) bool {
- nonLetter := false
- special := false // special letter
- for _, b := range s {
- if b >= utf8.RuneSelf {
- return bytes.EqualFold
- }
- upper := b & caseMask
- if upper < 'A' || upper > 'Z' {
- nonLetter = true
- } else if upper == 'K' || upper == 'S' {
- // See above for why these letters are special.
- special = true
- }
- }
- if special {
- return equalFoldRight
- }
- if nonLetter {
- return asciiEqualFold
- }
- return simpleLetterEqualFold
-}
-
-// equalFoldRight is a specialization of bytes.EqualFold when s is
-// known to be all ASCII (including punctuation), but contains an 's',
-// 'S', 'k', or 'K', requiring a Unicode fold on the bytes in t.
-// See comments on foldFunc.
-func equalFoldRight(s, t []byte) bool {
- for _, sb := range s {
- if len(t) == 0 {
- return false
- }
- tb := t[0]
- if tb < utf8.RuneSelf {
- if sb != tb {
- sbUpper := sb & caseMask
- if 'A' <= sbUpper && sbUpper <= 'Z' {
- if sbUpper != tb&caseMask {
- return false
- }
- } else {
- return false
- }
- }
- t = t[1:]
- continue
- }
- // sb is ASCII and t is not. t must be either kelvin
- // sign or long s; sb must be s, S, k, or K.
- tr, size := utf8.DecodeRune(t)
- switch sb {
- case 's', 'S':
- if tr != smallLongEss {
- return false
- }
- case 'k', 'K':
- if tr != kelvin {
- return false
- }
- default:
- return false
- }
- t = t[size:]
-
- }
- if len(t) > 0 {
- return false
- }
- return true
-}
-
-// asciiEqualFold is a specialization of bytes.EqualFold for use when
-// s is all ASCII (but may contain non-letters) and contains no
-// special-folding letters.
-// See comments on foldFunc.
-func asciiEqualFold(s, t []byte) bool {
- if len(s) != len(t) {
- return false
- }
- for i, sb := range s {
- tb := t[i]
- if sb == tb {
- continue
- }
- if ('a' <= sb && sb <= 'z') || ('A' <= sb && sb <= 'Z') {
- if sb&caseMask != tb&caseMask {
- return false
- }
- } else {
- return false
- }
- }
- return true
-}
-
-// simpleLetterEqualFold is a specialization of bytes.EqualFold for
-// use when s is all ASCII letters (no underscores, etc) and also
-// doesn't contain 'k', 'K', 's', or 'S'.
-// See comments on foldFunc.
-func simpleLetterEqualFold(s, t []byte) bool {
- if len(s) != len(t) {
- return false
- }
- for i, b := range s {
- if b&caseMask != t[i]&caseMask {
- return false
- }
- }
- return true
-}