don't handle format char at end.

fix https://gna.org/bugs/?7197

src/marked-up_text.cpp

@@ -317,7 +317,7 @@ std::string word_wrap_text(const std::string& unwrapped_text, int font_size, int
 		if(start_of_line) {
 			line_width = 0;
 			format_string = "";
-			while(ch != end && *ch < (wchar_t)0x100 && is_format_char(*ch)) {
+			while(ch != end && *ch < (wchar_t)0x100 && is_format_char(*ch) && !ch.next_is_end()) {
 				format_string.append(ch.substr().first, ch.substr().second);
 				++ch;
 			}

src/serialization/string_utils.cpp

@@ -437,6 +437,13 @@ wchar_t utf8_iterator::operator*() const
 	return current_char;
 }
 
+bool utf8_iterator::next_is_end()
+{
+	if(current_substr.second == string_end)
+		return true;
+	return false;
+}
+
 const std::pair<std::string::const_iterator, std::string::const_iterator>& utf8_iterator::substr() const
 {
 	return current_substr;

src/serialization/string_utils.hpp

@@ -96,6 +96,7 @@ public:
 	bool operator!=(const utf8_iterator& a) const { return ! (*this == a); }
 	utf8_iterator& operator++();
 	wchar_t operator*() const;
+	bool next_is_end();
 	const std::pair<std::string::const_iterator, std::string::const_iterator>& substr() const;
 private:
 	void update();