hunk.code_window:         "ClusterLogTimeoutMilliseconds": 2000,
           "EnablePreviewFeatures": true,
           "CloseUnusedDirectMessages": false,
           "EnableTutorial": true,
           "ExperimentalEnableDefaultChannelLeaveJoinMessages": true,
           "ImageProxyType": "",
           "ImageProxyURL": ""
       },
  
hunk.labels: keep keep keep keep add keep keep keep
hunk.after_edit:         "ExperimentalGroupUnreadChannels": false,
  
hunk.file_path: config/default.json
hunk.type: add
file: // 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 build
  
  import (
  	"fmt"
  	"io"
  	"reflect"
  	"sort"
  	"strings"
  
  	"golang.org/x/text/internal/colltab"
  )
  
  // This file contains code for detecting contractions and generating
  // the necessary tables.
  // Any Unicode Collation Algorithm (UCA) table entry that has more than
  // one rune one the left-hand side is called a contraction.
  // See http://www.unicode.org/reports/tr10/#Contractions for more details.
  //
  // We define the following terms:
  //   initial:     a rune that appears as the first rune in a contraction.
  //   suffix:      a sequence of runes succeeding the initial rune
  //                in a given contraction.
  //   non-initial: a rune that appears in a suffix.
  //
  // A rune may be both an initial and a non-initial and may be so in
  // many contractions.  An initial may typically also appear by itself.
  // In case of ambiguities, the UCA requires we match the longest
  // contraction.
  //
  // Many contraction rules share the same set of possible suffixes.
  // We store sets of suffixes in a trie that associates an index with
  // each suffix in the set.  This index can be used to look up a
  // collation element associated with the (starter rune, suffix) pair.
  //
  // The trie is defined on a UTF-8 byte sequence.
  // The overall trie is represented as an array of ctEntries.  Each node of the trie
  // is represented as a subsequence of ctEntries, where each entry corresponds to
  // a possible match of a next character in the search string.  An entry
  // also includes the length and offset to the next sequence of entries
  // to check in case of a match.
  
  const (
  	final   = 0
  	noIndex = 0xFF
  )
  
  // ctEntry associates to a matching byte an offset and/or next sequence of
  // bytes to check. A ctEntry c is called final if a match means that the
  // longest suffix has been found.  An entry c is final if c.N == 0.
  // A single final entry can match a range of characters to an offset.
  // A non-final entry always matches a single byte. Note that a non-final
  // entry might still resemble a completed suffix.
  // Examples:
  // The suffix strings "ab" and "ac" can be represented as:
  // []ctEntry{
  //     {'a', 1, 1, noIndex},  // 'a' by itself does not match, so i is 0xFF.
  //     {'b', 'c', 0, 1},   // "ab" -> 1, "ac" -> 2
  // }
  //
  // The suffix strings "ab", "abc", "abd", and "abcd" can be represented as:
  // []ctEntry{
  //     {'a', 1, 1, noIndex}, // 'a' must be followed by 'b'.
  //     {'b', 1, 2, 1},    // "ab" -> 1, may be followed by 'c' or 'd'.
  //     {'d', 'd', final, 3},  // "abd" -> 3
  //     {'c', 4, 1, 2},    // "abc" -> 2, may be followed by 'd'.
  //     {'d', 'd', final, 4},  // "abcd" -> 4
  // }
  // See genStateTests in contract_test.go for more examples.
  type ctEntry struct {
  	L uint8 // non-final: byte value to match; final: lowest match in range.
  	H uint8 // non-final: relative index to next block; final: highest match in range.
  	N uint8 // non-final: length of next block; final: final
  	I uint8 // result offset. Will be noIndex if more bytes are needed to complete.
  }
  
  // contractTrieSet holds a set of contraction tries. The tries are stored
  // consecutively in the entry field.
  type contractTrieSet []struct{ l, h, n, i uint8 }
  
  // ctHandle is used to identify a trie in the trie set, consisting in an offset
  // in the array and the size of the first node.
  type ctHandle struct {
  	index, n int
  }
  
  // appendTrie adds a new trie for the given suffixes to the trie set and returns
  // a handle to it.  The handle will be invalid on error.
  func appendTrie(ct *colltab.ContractTrieSet, suffixes []string) (ctHandle, error) {
  	es := make([]stridx, len(suffixes))
  	for i, s := range suffixes {
  		es[i].str = s
  	}
  	sort.Sort(offsetSort(es))
  	for i := range es {
  		es[i].index = i + 1
  	}
  	sort.Sort(genidxSort(es))
  	i := len(*ct)
  	n, err := genStates(ct, es)
  	if err != nil {
  		*ct = (*ct)[:i]
  		return ctHandle{}, err
  	}
  	return ctHandle{i, n}, nil
  }
  
  // genStates generates ctEntries for a given suffix set and returns
  // the number of entries for the first node.
  func genStates(ct *colltab.ContractTrieSet, sis []stridx) (int, error) {
  	if len(sis) == 0 {
  		return 0, fmt.Errorf("genStates: list of suffices must be non-empty")
  	}
  	start := len(*ct)
  	// create entries for differing first bytes.
  	for _, si := range sis {
  		s := si.str
  		if len(s) == 0 {
  			continue
  		}
  		added := false
  		c := s[0]
  		if len(s) > 1 {
  			for j := len(*ct) - 1; j >= start; j-- {
  				if (*ct)[j].L == c {
  					added = true
  					break
  				}
  			}
  			if !added {
  				*ct = append(*ct, ctEntry{L: c, I: noIndex})
  			}
  		} else {
  			for j := len(*ct) - 1; j >= start; j-- {
  				// Update the offset for longer suffixes with the same byte.
  				if (*ct)[j].L == c {
  					(*ct)[j].I = uint8(si.index)
  					added = true
  				}
  				// Extend range of final ctEntry, if possible.
  				if (*ct)[j].H+1 == c {
  					(*ct)[j].H = c
  					added = true
  				}
  			}
  			if !added {
  				*ct = append(*ct, ctEntry{L: c, H: c, N: final, I: uint8(si.index)})
  			}
  		}
  	}
  	n := len(*ct) - start
  	// Append nodes for the remainder of the suffixes for each ctEntry.
  	sp := 0
  	for i, end := start, len(*ct); i < end; i++ {
  		fe := (*ct)[i]
  		if fe.H == 0 { // uninitialized non-final
  			ln := len(*ct) - start - n
  			if ln > 0xFF {
  				return 0, fmt.Errorf("genStates: relative block offset too large: %d > 255", ln)
  			}
  			fe.H = uint8(ln)
  			// Find first non-final strings with same byte as current entry.
  			for ; sis[sp].str[0] != fe.L; sp++ {
  			}
  			se := sp + 1
  			for ; se < len(sis) && len(sis[se].str) > 1 && sis[se].str[0] == fe.L; se++ {
  			}
  			sl := sis[sp:se]
  			sp = se
  			for i, si := range sl {
  				sl[i].str = si.str[1:]
  			}
  			nn, err := genStates(ct, sl)
  			if err != nil {
  				return 0, err
  			}
  			fe.N = uint8(nn)
  			(*ct)[i] = fe
  		}
  	}
  	sort.Sort(entrySort((*ct)[start : start+n]))
  	return n, nil
  }
  
  // There may be both a final and non-final entry for a byte if the byte
  // is implied in a range of matches in the final entry.
  // We need to ensure that the non-final entry comes first in that case.
  type entrySort colltab.ContractTrieSet
  
  func (fe entrySort) Len() int      { return len(fe) }
  func (fe entrySort) Swap(i, j int) { fe[i], fe[j] = fe[j], fe[i] }
  func (fe entrySort) Less(i, j int) bool {
  	return fe[i].L > fe[j].L
  }
  
  // stridx is used for sorting suffixes and their associated offsets.
  type stridx struct {
  	str   string
  	index int
  }
  
  // For computing the offsets, we first sort by size, and then by string.
  // This ensures that strings that only differ in the last byte by 1
  // are sorted consecutively in increasing order such that they can
  // be packed as a range in a final ctEntry.
  type offsetSort []stridx
  
  func (si offsetSort) Len() int      { return len(si) }
  func (si offsetSort) Swap(i, j int) { si[i], si[j] = si[j], si[i] }
  func (si offsetSort) Less(i, j int) bool {
  	if len(si[i].str) != len(si[j].str) {
  		return len(si[i].str) > len(si[j].str)
  	}
  	return si[i].str < si[j].str
  }
  
  // For indexing, we want to ensure that strings are sorted in string order, where
  // for strings with the same prefix, we put longer strings before shorter ones.
  type genidxSort []stridx
  
  func (si genidxSort) Len() int      { return len(si) }
  func (si genidxSort) Swap(i, j int) { si[i], si[j] = si[j], si[i] }
  func (si genidxSort) Less(i, j int) bool {
  	if strings.HasPrefix(si[j].str, si[i].str) {
  		return false
  	}
  	if strings.HasPrefix(si[i].str, si[j].str) {
  		return true
  	}
  	return si[i].str < si[j].str
  }
  
  // lookup matches the longest suffix in str and returns the associated offset
  // and the number of bytes consumed.
  func lookup(ct *colltab.ContractTrieSet, h ctHandle, str []byte) (index, ns int) {
  	states := (*ct)[h.index:]
  	p := 0
  	n := h.n
  	for i := 0; i < n && p < len(str); {
  		e := states[i]
  		c := str[p]
  		if c >= e.L {
  			if e.L == c {
  				p++
  				if e.I != noIndex {
  					index, ns = int(e.I), p
  				}
  				if e.N != final {
  					// set to new state
  					i, states, n = 0, states[int(e.H)+n:], int(e.N)
  				} else {
  					return
  				}
  				continue
  			} else if e.N == final && c <= e.H {
  				p++
  				return int(c-e.L) + int(e.I), p
  			}
  		}
  		i++
  	}
  	return
  }
  
  // print writes the contractTrieSet t as compilable Go code to w. It returns
  // the total number of bytes written and the size of the resulting data structure in bytes.
  func print(t *colltab.ContractTrieSet, w io.Writer, name string) (n, size int, err error) {
  	update3 := func(nn, sz int, e error) {
  		n += nn
  		if err == nil {
  			err = e
  		}
  		size += sz
  	}
  	update2 := func(nn int, e error) { update3(nn, 0, e) }
  
  	update3(printArray(*t, w, name))
  	update2(fmt.Fprintf(w, "var %sContractTrieSet = ", name))
  	update3(printStruct(*t, w, name))
  	update2(fmt.Fprintln(w))
  	return
  }
  
  func printArray(ct colltab.ContractTrieSet, w io.Writer, name string) (n, size int, err error) {
  	p := func(f string, a ...interface{}) {
  		nn, e := fmt.Fprintf(w, f, a...)
  		n += nn
  		if err == nil {
  			err = e
  		}
  	}
  	size = len(ct) * 4
  	p("// %sCTEntries: %d entries, %d bytes\n", name, len(ct), size)
  	p("var %sCTEntries = [%d]struct{L,H,N,I uint8}{\n", name, len(ct))
  	for _, fe := range ct {
  		p("\t{0x%X, 0x%X, %d, %d},\n", fe.L, fe.H, fe.N, fe.I)
  	}
  	p("}\n")
  	return
  }
  
  func printStruct(ct colltab.ContractTrieSet, w io.Writer, name string) (n, size int, err error) {
  	n, err = fmt.Fprintf(w, "colltab.ContractTrieSet( %sCTEntries[:] )", name)
  	size = int(reflect.TypeOf(ct).Size())
  	return
  }
  