diff options
Diffstat (limited to 'vendor/github.com/matterbridge/msgraph.go/jsonx/fold.go')
-rw-r--r-- | vendor/github.com/matterbridge/msgraph.go/jsonx/fold.go | 143 |
1 files changed, 0 insertions, 143 deletions
diff --git a/vendor/github.com/matterbridge/msgraph.go/jsonx/fold.go b/vendor/github.com/matterbridge/msgraph.go/jsonx/fold.go deleted file mode 100644 index 316ea018..00000000 --- a/vendor/github.com/matterbridge/msgraph.go/jsonx/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 jsonx - -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 -} |