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authorChristoph Blecker <admin@toph.ca>2018-03-04 14:36:40 -0800
committerChristoph Blecker <admin@toph.ca>2018-03-05 09:31:45 -0800
commit5c3b5582924ff744831fca08572b54d5c8f86a2d (patch)
treeb8a917087a1aa80e4e0bc5d2d3a09da7a0c9a734 /vendor/github.com/client9/misspell/stringreplacer.go
parent2bd679812c5cc204ba7c329451effa56151142ac (diff)
Move vendor to root, add misspell util
Diffstat (limited to 'vendor/github.com/client9/misspell/stringreplacer.go')
-rw-r--r--vendor/github.com/client9/misspell/stringreplacer.go336
1 files changed, 336 insertions, 0 deletions
diff --git a/vendor/github.com/client9/misspell/stringreplacer.go b/vendor/github.com/client9/misspell/stringreplacer.go
new file mode 100644
index 00000000..3151eceb
--- /dev/null
+++ b/vendor/github.com/client9/misspell/stringreplacer.go
@@ -0,0 +1,336 @@
+// Copyright 2011 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 misspell
+
+import (
+ "io"
+ // "log"
+ "strings"
+)
+
+// StringReplacer replaces a list of strings with replacements.
+// It is safe for concurrent use by multiple goroutines.
+type StringReplacer struct {
+ r replacer
+}
+
+// replacer is the interface that a replacement algorithm needs to implement.
+type replacer interface {
+ Replace(s string) string
+ WriteString(w io.Writer, s string) (n int, err error)
+}
+
+// NewStringReplacer returns a new Replacer from a list of old, new string pairs.
+// Replacements are performed in order, without overlapping matches.
+func NewStringReplacer(oldnew ...string) *StringReplacer {
+ if len(oldnew)%2 == 1 {
+ panic("strings.NewReplacer: odd argument count")
+ }
+
+ return &StringReplacer{r: makeGenericReplacer(oldnew)}
+}
+
+// Replace returns a copy of s with all replacements performed.
+func (r *StringReplacer) Replace(s string) string {
+ return r.r.Replace(s)
+}
+
+// WriteString writes s to w with all replacements performed.
+func (r *StringReplacer) WriteString(w io.Writer, s string) (n int, err error) {
+ return r.r.WriteString(w, s)
+}
+
+// trieNode is a node in a lookup trie for prioritized key/value pairs. Keys
+// and values may be empty. For example, the trie containing keys "ax", "ay",
+// "bcbc", "x" and "xy" could have eight nodes:
+//
+// n0 -
+// n1 a-
+// n2 .x+
+// n3 .y+
+// n4 b-
+// n5 .cbc+
+// n6 x+
+// n7 .y+
+//
+// n0 is the root node, and its children are n1, n4 and n6; n1's children are
+// n2 and n3; n4's child is n5; n6's child is n7. Nodes n0, n1 and n4 (marked
+// with a trailing "-") are partial keys, and nodes n2, n3, n5, n6 and n7
+// (marked with a trailing "+") are complete keys.
+type trieNode struct {
+ // value is the value of the trie node's key/value pair. It is empty if
+ // this node is not a complete key.
+ value string
+ // priority is the priority (higher is more important) of the trie node's
+ // key/value pair; keys are not necessarily matched shortest- or longest-
+ // first. Priority is positive if this node is a complete key, and zero
+ // otherwise. In the example above, positive/zero priorities are marked
+ // with a trailing "+" or "-".
+ priority int
+
+ // A trie node may have zero, one or more child nodes:
+ // * if the remaining fields are zero, there are no children.
+ // * if prefix and next are non-zero, there is one child in next.
+ // * if table is non-zero, it defines all the children.
+ //
+ // Prefixes are preferred over tables when there is one child, but the
+ // root node always uses a table for lookup efficiency.
+
+ // prefix is the difference in keys between this trie node and the next.
+ // In the example above, node n4 has prefix "cbc" and n4's next node is n5.
+ // Node n5 has no children and so has zero prefix, next and table fields.
+ prefix string
+ next *trieNode
+
+ // table is a lookup table indexed by the next byte in the key, after
+ // remapping that byte through genericReplacer.mapping to create a dense
+ // index. In the example above, the keys only use 'a', 'b', 'c', 'x' and
+ // 'y', which remap to 0, 1, 2, 3 and 4. All other bytes remap to 5, and
+ // genericReplacer.tableSize will be 5. Node n0's table will be
+ // []*trieNode{ 0:n1, 1:n4, 3:n6 }, where the 0, 1 and 3 are the remapped
+ // 'a', 'b' and 'x'.
+ table []*trieNode
+}
+
+func (t *trieNode) add(key, val string, priority int, r *genericReplacer) {
+ if key == "" {
+ if t.priority == 0 {
+ t.value = val
+ t.priority = priority
+ }
+ return
+ }
+
+ if t.prefix != "" {
+ // Need to split the prefix among multiple nodes.
+ var n int // length of the longest common prefix
+ for ; n < len(t.prefix) && n < len(key); n++ {
+ if t.prefix[n] != key[n] {
+ break
+ }
+ }
+ if n == len(t.prefix) {
+ t.next.add(key[n:], val, priority, r)
+ } else if n == 0 {
+ // First byte differs, start a new lookup table here. Looking up
+ // what is currently t.prefix[0] will lead to prefixNode, and
+ // looking up key[0] will lead to keyNode.
+ var prefixNode *trieNode
+ if len(t.prefix) == 1 {
+ prefixNode = t.next
+ } else {
+ prefixNode = &trieNode{
+ prefix: t.prefix[1:],
+ next: t.next,
+ }
+ }
+ keyNode := new(trieNode)
+ t.table = make([]*trieNode, r.tableSize)
+ t.table[r.mapping[t.prefix[0]]] = prefixNode
+ t.table[r.mapping[key[0]]] = keyNode
+ t.prefix = ""
+ t.next = nil
+ keyNode.add(key[1:], val, priority, r)
+ } else {
+ // Insert new node after the common section of the prefix.
+ next := &trieNode{
+ prefix: t.prefix[n:],
+ next: t.next,
+ }
+ t.prefix = t.prefix[:n]
+ t.next = next
+ next.add(key[n:], val, priority, r)
+ }
+ } else if t.table != nil {
+ // Insert into existing table.
+ m := r.mapping[key[0]]
+ if t.table[m] == nil {
+ t.table[m] = new(trieNode)
+ }
+ t.table[m].add(key[1:], val, priority, r)
+ } else {
+ t.prefix = key
+ t.next = new(trieNode)
+ t.next.add("", val, priority, r)
+ }
+}
+
+func (r *genericReplacer) lookup(s string, ignoreRoot bool) (val string, keylen int, found bool) {
+ // Iterate down the trie to the end, and grab the value and keylen with
+ // the highest priority.
+ bestPriority := 0
+ node := &r.root
+ n := 0
+ for node != nil {
+ if node.priority > bestPriority && !(ignoreRoot && node == &r.root) {
+ bestPriority = node.priority
+ val = node.value
+ keylen = n
+ found = true
+ }
+
+ if s == "" {
+ break
+ }
+ if node.table != nil {
+ index := r.mapping[ByteToLower(s[0])]
+ if int(index) == r.tableSize {
+ break
+ }
+ node = node.table[index]
+ s = s[1:]
+ n++
+ } else if node.prefix != "" && StringHasPrefixFold(s, node.prefix) {
+ n += len(node.prefix)
+ s = s[len(node.prefix):]
+ node = node.next
+ } else {
+ break
+ }
+ }
+ return
+}
+
+// genericReplacer is the fully generic algorithm.
+// It's used as a fallback when nothing faster can be used.
+type genericReplacer struct {
+ root trieNode
+ // tableSize is the size of a trie node's lookup table. It is the number
+ // of unique key bytes.
+ tableSize int
+ // mapping maps from key bytes to a dense index for trieNode.table.
+ mapping [256]byte
+}
+
+func makeGenericReplacer(oldnew []string) *genericReplacer {
+ r := new(genericReplacer)
+ // Find each byte used, then assign them each an index.
+ for i := 0; i < len(oldnew); i += 2 {
+ key := strings.ToLower(oldnew[i])
+ for j := 0; j < len(key); j++ {
+ r.mapping[key[j]] = 1
+ }
+ }
+
+ for _, b := range r.mapping {
+ r.tableSize += int(b)
+ }
+
+ var index byte
+ for i, b := range r.mapping {
+ if b == 0 {
+ r.mapping[i] = byte(r.tableSize)
+ } else {
+ r.mapping[i] = index
+ index++
+ }
+ }
+ // Ensure root node uses a lookup table (for performance).
+ r.root.table = make([]*trieNode, r.tableSize)
+
+ for i := 0; i < len(oldnew); i += 2 {
+ r.root.add(strings.ToLower(oldnew[i]), oldnew[i+1], len(oldnew)-i, r)
+ }
+ return r
+}
+
+type appendSliceWriter []byte
+
+// Write writes to the buffer to satisfy io.Writer.
+func (w *appendSliceWriter) Write(p []byte) (int, error) {
+ *w = append(*w, p...)
+ return len(p), nil
+}
+
+// WriteString writes to the buffer without string->[]byte->string allocations.
+func (w *appendSliceWriter) WriteString(s string) (int, error) {
+ *w = append(*w, s...)
+ return len(s), nil
+}
+
+type stringWriterIface interface {
+ WriteString(string) (int, error)
+}
+
+type stringWriter struct {
+ w io.Writer
+}
+
+func (w stringWriter) WriteString(s string) (int, error) {
+ return w.w.Write([]byte(s))
+}
+
+func getStringWriter(w io.Writer) stringWriterIface {
+ sw, ok := w.(stringWriterIface)
+ if !ok {
+ sw = stringWriter{w}
+ }
+ return sw
+}
+
+func (r *genericReplacer) Replace(s string) string {
+ buf := make(appendSliceWriter, 0, len(s))
+ r.WriteString(&buf, s)
+ return string(buf)
+}
+
+func (r *genericReplacer) WriteString(w io.Writer, s string) (n int, err error) {
+ sw := getStringWriter(w)
+ var last, wn int
+ var prevMatchEmpty bool
+ for i := 0; i <= len(s); {
+ // Fast path: s[i] is not a prefix of any pattern.
+ if i != len(s) && r.root.priority == 0 {
+ index := int(r.mapping[ByteToLower(s[i])])
+ if index == r.tableSize || r.root.table[index] == nil {
+ i++
+ continue
+ }
+ }
+
+ // Ignore the empty match iff the previous loop found the empty match.
+ val, keylen, match := r.lookup(s[i:], prevMatchEmpty)
+ prevMatchEmpty = match && keylen == 0
+ if match {
+ orig := s[i : i+keylen]
+ switch CaseStyle(orig) {
+ case CaseUnknown:
+ // pretend we didn't match
+ // i++
+ // continue
+ case CaseUpper:
+ val = strings.ToUpper(val)
+ case CaseLower:
+ val = strings.ToLower(val)
+ case CaseTitle:
+ if len(val) < 2 {
+ val = strings.ToUpper(val)
+ } else {
+ val = strings.ToUpper(val[:1]) + strings.ToLower(val[1:])
+ }
+ }
+ wn, err = sw.WriteString(s[last:i])
+ n += wn
+ if err != nil {
+ return
+ }
+ //log.Printf("%d: Going to correct %q with %q", i, s[i:i+keylen], val)
+ wn, err = sw.WriteString(val)
+ n += wn
+ if err != nil {
+ return
+ }
+ i += keylen
+ last = i
+ continue
+ }
+ i++
+ }
+ if last != len(s) {
+ wn, err = sw.WriteString(s[last:])
+ n += wn
+ }
+ return
+}