From 7b320119ba532fd409ec7dade7ad02011c309599 Mon Sep 17 00:00:00 2001 From: Niall Sheridan Date: Wed, 18 Oct 2017 13:15:14 +0100 Subject: Update dependencies --- .../golang.org/x/text/internal/colltab/contract.go | 145 +++++++++++++++++++++ 1 file changed, 145 insertions(+) create mode 100644 vendor/golang.org/x/text/internal/colltab/contract.go (limited to 'vendor/golang.org/x/text/internal/colltab/contract.go') diff --git a/vendor/golang.org/x/text/internal/colltab/contract.go b/vendor/golang.org/x/text/internal/colltab/contract.go new file mode 100644 index 0000000..25649d4 --- /dev/null +++ b/vendor/golang.org/x/text/internal/colltab/contract.go @@ -0,0 +1,145 @@ +// Copyright 2012 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 colltab + +import "unicode/utf8" + +// For a description of ContractTrieSet, see text/collate/build/contract.go. + +type ContractTrieSet []struct{ L, H, N, I uint8 } + +// ctScanner is used to match a trie to an input sequence. +// A contraction may match a non-contiguous sequence of bytes in an input string. +// For example, if there is a contraction for , it should match +// the sequence , as combining_cedilla does +// not block combining_ring. +// ctScanner does not automatically skip over non-blocking non-starters, but rather +// retains the state of the last match and leaves it up to the user to continue +// the match at the appropriate points. +type ctScanner struct { + states ContractTrieSet + s []byte + n int + index int + pindex int + done bool +} + +type ctScannerString struct { + states ContractTrieSet + s string + n int + index int + pindex int + done bool +} + +func (t ContractTrieSet) scanner(index, n int, b []byte) ctScanner { + return ctScanner{s: b, states: t[index:], n: n} +} + +func (t ContractTrieSet) scannerString(index, n int, str string) ctScannerString { + return ctScannerString{s: str, states: t[index:], n: n} +} + +// result returns the offset i and bytes consumed p so far. If no suffix +// matched, i and p will be 0. +func (s *ctScanner) result() (i, p int) { + return s.index, s.pindex +} + +func (s *ctScannerString) result() (i, p int) { + return s.index, s.pindex +} + +const ( + final = 0 + noIndex = 0xFF +) + +// scan matches the longest suffix at the current location in the input +// and returns the number of bytes consumed. +func (s *ctScanner) scan(p int) int { + pr := p // the p at the rune start + str := s.s + states, n := s.states, s.n + for i := 0; i < n && p < len(str); { + e := states[i] + c := str[p] + // TODO: a significant number of contractions are of a form that + // cannot match discontiguous UTF-8 in a normalized string. We could let + // a negative value of e.n mean that we can set s.done = true and avoid + // the need for additional matches. + if c >= e.L { + if e.L == c { + p++ + if e.I != noIndex { + s.index = int(e.I) + s.pindex = p + } + if e.N != final { + i, states, n = 0, states[int(e.H)+n:], int(e.N) + if p >= len(str) || utf8.RuneStart(str[p]) { + s.states, s.n, pr = states, n, p + } + } else { + s.done = true + return p + } + continue + } else if e.N == final && c <= e.H { + p++ + s.done = true + s.index = int(c-e.L) + int(e.I) + s.pindex = p + return p + } + } + i++ + } + return pr +} + +// scan is a verbatim copy of ctScanner.scan. +func (s *ctScannerString) scan(p int) int { + pr := p // the p at the rune start + str := s.s + states, n := s.states, s.n + for i := 0; i < n && p < len(str); { + e := states[i] + c := str[p] + // TODO: a significant number of contractions are of a form that + // cannot match discontiguous UTF-8 in a normalized string. We could let + // a negative value of e.n mean that we can set s.done = true and avoid + // the need for additional matches. + if c >= e.L { + if e.L == c { + p++ + if e.I != noIndex { + s.index = int(e.I) + s.pindex = p + } + if e.N != final { + i, states, n = 0, states[int(e.H)+n:], int(e.N) + if p >= len(str) || utf8.RuneStart(str[p]) { + s.states, s.n, pr = states, n, p + } + } else { + s.done = true + return p + } + continue + } else if e.N == final && c <= e.H { + p++ + s.done = true + s.index = int(c-e.L) + int(e.I) + s.pindex = p + return p + } + } + i++ + } + return pr +} -- cgit v1.2.3