More expansions in template repositories (#10021)

* Super expansion
* Explain which features are in 1.11 vs 1.12
* Move imports

Signed-off-by: jolheiser <john.olheiser@gmail.com>

vendor/github.com/huandu/xstrings/count.go

@@ -0,0 +1,120 @@
+// Copyright 2015 Huan Du. All rights reserved.
+// Licensed under the MIT license that can be found in the LICENSE file.
+
+package xstrings
+
+import (
+	"unicode"
+	"unicode/utf8"
+)
+
+// Len returns str's utf8 rune length.
+func Len(str string) int {
+	return utf8.RuneCountInString(str)
+}
+
+// WordCount returns number of words in a string.
+//
+// Word is defined as a locale dependent string containing alphabetic characters,
+// which may also contain but not start with `'` and `-` characters.
+func WordCount(str string) int {
+	var r rune
+	var size, n int
+
+	inWord := false
+
+	for len(str) > 0 {
+		r, size = utf8.DecodeRuneInString(str)
+
+		switch {
+		case isAlphabet(r):
+			if !inWord {
+				inWord = true
+				n++
+			}
+
+		case inWord && (r == '\'' || r == '-'):
+			// Still in word.
+
+		default:
+			inWord = false
+		}
+
+		str = str[size:]
+	}
+
+	return n
+}
+
+const minCJKCharacter = '\u3400'
+
+// Checks r is a letter but not CJK character.
+func isAlphabet(r rune) bool {
+	if !unicode.IsLetter(r) {
+		return false
+	}
+
+	switch {
+	// Quick check for non-CJK character.
+	case r < minCJKCharacter:
+		return true
+
+	// Common CJK characters.
+	case r >= '\u4E00' && r <= '\u9FCC':
+		return false
+
+	// Rare CJK characters.
+	case r >= '\u3400' && r <= '\u4D85':
+		return false
+
+	// Rare and historic CJK characters.
+	case r >= '\U00020000' && r <= '\U0002B81D':
+		return false
+	}
+
+	return true
+}
+
+// Width returns string width in monotype font.
+// Multi-byte characters are usually twice the width of single byte characters.
+//
+// Algorithm comes from `mb_strwidth` in PHP.
+// http://php.net/manual/en/function.mb-strwidth.php
+func Width(str string) int {
+	var r rune
+	var size, n int
+
+	for len(str) > 0 {
+		r, size = utf8.DecodeRuneInString(str)
+		n += RuneWidth(r)
+		str = str[size:]
+	}
+
+	return n
+}
+
+// RuneWidth returns character width in monotype font.
+// Multi-byte characters are usually twice the width of single byte characters.
+//
+// Algorithm comes from `mb_strwidth` in PHP.
+// http://php.net/manual/en/function.mb-strwidth.php
+func RuneWidth(r rune) int {
+	switch {
+	case r == utf8.RuneError || r < '\x20':
+		return 0
+
+	case '\x20' <= r && r < '\u2000':
+		return 1
+
+	case '\u2000' <= r && r < '\uFF61':
+		return 2
+
+	case '\uFF61' <= r && r < '\uFFA0':
+		return 1
+
+	case '\uFFA0' <= r:
+		return 2
+	}
+
+	return 0
+}