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Diffstat (limited to 'vendor/golang.org/x/text/unicode/bidi/prop.go')
| -rw-r--r-- | vendor/golang.org/x/text/unicode/bidi/prop.go | 206 |
1 files changed, 0 insertions, 206 deletions
diff --git a/vendor/golang.org/x/text/unicode/bidi/prop.go b/vendor/golang.org/x/text/unicode/bidi/prop.go deleted file mode 100644 index 7c9484e..0000000 --- a/vendor/golang.org/x/text/unicode/bidi/prop.go +++ /dev/null @@ -1,206 +0,0 @@ -// Copyright 2016 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 bidi - -import "unicode/utf8" - -// Properties provides access to BiDi properties of runes. -type Properties struct { - entry uint8 - last uint8 -} - -var trie = newBidiTrie(0) - -// TODO: using this for bidirule reduces the running time by about 5%. Consider -// if this is worth exposing or if we can find a way to speed up the Class -// method. -// -// // CompactClass is like Class, but maps all of the BiDi control classes -// // (LRO, RLO, LRE, RLE, PDF, LRI, RLI, FSI, PDI) to the class Control. -// func (p Properties) CompactClass() Class { -// return Class(p.entry & 0x0F) -// } - -// Class returns the Bidi class for p. -func (p Properties) Class() Class { - c := Class(p.entry & 0x0F) - if c == Control { - c = controlByteToClass[p.last&0xF] - } - return c -} - -// IsBracket reports whether the rune is a bracket. -func (p Properties) IsBracket() bool { return p.entry&0xF0 != 0 } - -// IsOpeningBracket reports whether the rune is an opening bracket. -// IsBracket must return true. -func (p Properties) IsOpeningBracket() bool { return p.entry&openMask != 0 } - -// TODO: find a better API and expose. -func (p Properties) reverseBracket(r rune) rune { - return xorMasks[p.entry>>xorMaskShift] ^ r -} - -var controlByteToClass = [16]Class{ - 0xD: LRO, // U+202D LeftToRightOverride, - 0xE: RLO, // U+202E RightToLeftOverride, - 0xA: LRE, // U+202A LeftToRightEmbedding, - 0xB: RLE, // U+202B RightToLeftEmbedding, - 0xC: PDF, // U+202C PopDirectionalFormat, - 0x6: LRI, // U+2066 LeftToRightIsolate, - 0x7: RLI, // U+2067 RightToLeftIsolate, - 0x8: FSI, // U+2068 FirstStrongIsolate, - 0x9: PDI, // U+2069 PopDirectionalIsolate, -} - -// LookupRune returns properties for r. -func LookupRune(r rune) (p Properties, size int) { - var buf [4]byte - n := utf8.EncodeRune(buf[:], r) - return Lookup(buf[:n]) -} - -// TODO: these lookup methods are based on the generated trie code. The returned -// sizes have slightly different semantics from the generated code, in that it -// always returns size==1 for an illegal UTF-8 byte (instead of the length -// of the maximum invalid subsequence). Most Transformers, like unicode/norm, -// leave invalid UTF-8 untouched, in which case it has performance benefits to -// do so (without changing the semantics). Bidi requires the semantics used here -// for the bidirule implementation to be compatible with the Go semantics. -// They ultimately should perhaps be adopted by all trie implementations, for -// convenience sake. -// This unrolled code also boosts performance of the secure/bidirule package by -// about 30%. -// So, to remove this code: -// - add option to trie generator to define return type. -// - always return 1 byte size for ill-formed UTF-8 runes. - -// Lookup returns properties for the first rune in s and the width in bytes of -// its encoding. The size will be 0 if s does not hold enough bytes to complete -// the encoding. -func Lookup(s []byte) (p Properties, sz int) { - c0 := s[0] - switch { - case c0 < 0x80: // is ASCII - return Properties{entry: bidiValues[c0]}, 1 - case c0 < 0xC2: - return Properties{}, 1 - case c0 < 0xE0: // 2-byte UTF-8 - if len(s) < 2 { - return Properties{}, 0 - } - i := bidiIndex[c0] - c1 := s[1] - if c1 < 0x80 || 0xC0 <= c1 { - return Properties{}, 1 - } - return Properties{entry: trie.lookupValue(uint32(i), c1)}, 2 - case c0 < 0xF0: // 3-byte UTF-8 - if len(s) < 3 { - return Properties{}, 0 - } - i := bidiIndex[c0] - c1 := s[1] - if c1 < 0x80 || 0xC0 <= c1 { - return Properties{}, 1 - } - o := uint32(i)<<6 + uint32(c1) - i = bidiIndex[o] - c2 := s[2] - if c2 < 0x80 || 0xC0 <= c2 { - return Properties{}, 1 - } - return Properties{entry: trie.lookupValue(uint32(i), c2), last: c2}, 3 - case c0 < 0xF8: // 4-byte UTF-8 - if len(s) < 4 { - return Properties{}, 0 - } - i := bidiIndex[c0] - c1 := s[1] - if c1 < 0x80 || 0xC0 <= c1 { - return Properties{}, 1 - } - o := uint32(i)<<6 + uint32(c1) - i = bidiIndex[o] - c2 := s[2] - if c2 < 0x80 || 0xC0 <= c2 { - return Properties{}, 1 - } - o = uint32(i)<<6 + uint32(c2) - i = bidiIndex[o] - c3 := s[3] - if c3 < 0x80 || 0xC0 <= c3 { - return Properties{}, 1 - } - return Properties{entry: trie.lookupValue(uint32(i), c3)}, 4 - } - // Illegal rune - return Properties{}, 1 -} - -// LookupString returns properties for the first rune in s and the width in -// bytes of its encoding. The size will be 0 if s does not hold enough bytes to -// complete the encoding. -func LookupString(s string) (p Properties, sz int) { - c0 := s[0] - switch { - case c0 < 0x80: // is ASCII - return Properties{entry: bidiValues[c0]}, 1 - case c0 < 0xC2: - return Properties{}, 1 - case c0 < 0xE0: // 2-byte UTF-8 - if len(s) < 2 { - return Properties{}, 0 - } - i := bidiIndex[c0] - c1 := s[1] - if c1 < 0x80 || 0xC0 <= c1 { - return Properties{}, 1 - } - return Properties{entry: trie.lookupValue(uint32(i), c1)}, 2 - case c0 < 0xF0: // 3-byte UTF-8 - if len(s) < 3 { - return Properties{}, 0 - } - i := bidiIndex[c0] - c1 := s[1] - if c1 < 0x80 || 0xC0 <= c1 { - return Properties{}, 1 - } - o := uint32(i)<<6 + uint32(c1) - i = bidiIndex[o] - c2 := s[2] - if c2 < 0x80 || 0xC0 <= c2 { - return Properties{}, 1 - } - return Properties{entry: trie.lookupValue(uint32(i), c2), last: c2}, 3 - case c0 < 0xF8: // 4-byte UTF-8 - if len(s) < 4 { - return Properties{}, 0 - } - i := bidiIndex[c0] - c1 := s[1] - if c1 < 0x80 || 0xC0 <= c1 { - return Properties{}, 1 - } - o := uint32(i)<<6 + uint32(c1) - i = bidiIndex[o] - c2 := s[2] - if c2 < 0x80 || 0xC0 <= c2 { - return Properties{}, 1 - } - o = uint32(i)<<6 + uint32(c2) - i = bidiIndex[o] - c3 := s[3] - if c3 < 0x80 || 0xC0 <= c3 { - return Properties{}, 1 - } - return Properties{entry: trie.lookupValue(uint32(i), c3)}, 4 - } - // Illegal rune - return Properties{}, 1 -} |