M esc.go → esc.go

@@ -17,15 +17,41 @@ var start, end int
 	for end < len(s) {
 		escSeq := htmlEscaper[s[end]]
 		if escSeq != nil {
-			w.Write(s[start:end])
-			w.Write(escSeq)
-			start = end + 1
+			isEntity, entityEnd := nodeIsEntity(s, end)
+			if isEntity {
+				w.Write(s[start : entityEnd+1])
+				start = entityEnd + 1
+			} else {
+				w.Write(s[start:end])
+				w.Write(escSeq)
+				start = end + 1
+			}
 		}
 		end++
 	}
 	if start < len(s) && end <= len(s) {
 		w.Write(s[start:end])
 	}
+}
+
+func nodeIsEntity(s []byte, end int) (isEntity bool, endEntityPos int) {
+	isEntity = false
+	endEntityPos = end + 1
+
+	if s[end] == '&' {
+		for endEntityPos < len(s) {
+			if s[endEntityPos] == ';' {
+				isEntity = true
+				break
+			}
+			if !isalnum(s[endEntityPos]) && s[endEntityPos] != '&' && s[endEntityPos] != '#' {
+				break
+			}
+			endEntityPos++
+		}
+	}
+
+	return isEntity, endEntityPos
 }
 
 func escLink(w io.Writer, text []byte) {