working commit

vendor/github.com/mitchellh/go-wordwrap/wordwrap.go

@@ -0,0 +1,83 @@
+package wordwrap
+
+import (
+	"bytes"
+	"unicode"
+)
+
+const nbsp = 0xA0
+
+// WrapString wraps the given string within lim width in characters.
+//
+// Wrapping is currently naive and only happens at white-space. A future
+// version of the library will implement smarter wrapping. This means that
+// pathological cases can dramatically reach past the limit, such as a very
+// long word.
+func WrapString(s string, lim uint) string {
+	// Initialize a buffer with a slightly larger size to account for breaks
+	init := make([]byte, 0, len(s))
+	buf := bytes.NewBuffer(init)
+
+	var current uint
+	var wordBuf, spaceBuf bytes.Buffer
+	var wordBufLen, spaceBufLen uint
+
+	for _, char := range s {
+		if char == '\n' {
+			if wordBuf.Len() == 0 {
+				if current+spaceBufLen > lim {
+					current = 0
+				} else {
+					current += spaceBufLen
+					spaceBuf.WriteTo(buf)
+				}
+				spaceBuf.Reset()
+				spaceBufLen = 0
+			} else {
+				current += spaceBufLen + wordBufLen
+				spaceBuf.WriteTo(buf)
+				spaceBuf.Reset()
+				spaceBufLen = 0
+				wordBuf.WriteTo(buf)
+				wordBuf.Reset()
+				wordBufLen = 0
+			}
+			buf.WriteRune(char)
+			current = 0
+		} else if unicode.IsSpace(char) && char != nbsp {
+			if spaceBuf.Len() == 0 || wordBuf.Len() > 0 {
+				current += spaceBufLen + wordBufLen
+				spaceBuf.WriteTo(buf)
+				spaceBuf.Reset()
+				spaceBufLen = 0
+				wordBuf.WriteTo(buf)
+				wordBuf.Reset()
+				wordBufLen = 0
+			}
+
+			spaceBuf.WriteRune(char)
+			spaceBufLen++
+		} else {
+			wordBuf.WriteRune(char)
+			wordBufLen++
+
+			if current+wordBufLen+spaceBufLen > lim && wordBufLen < lim {
+				buf.WriteRune('\n')
+				current = 0
+				spaceBuf.Reset()
+				spaceBufLen = 0
+			}
+		}
+	}
+
+	if wordBuf.Len() == 0 {
+		if current+spaceBufLen <= lim {
+			spaceBuf.WriteTo(buf)
+		}
+	} else {
+		spaceBuf.WriteTo(buf)
+		wordBuf.WriteTo(buf)
+	}
+
+	return buf.String()
+}