replace char: fix unicode handling

src/input_handler.cc

@@ -61,14 +61,6 @@ private:
     int m_count = 0;
 };
 
-String codepoint_to_str(Codepoint cp)
-{
-    std::string str;
-    auto it = back_inserter(str);
-    utf8::dump(it, cp);
-    return String(str);
-}
-
 class LineEditor
 {
 public:

src/main.cc

@@ -102,7 +102,7 @@ void do_replace_with_char(Context& context)
         SelectionList sels = editor.selections();
         auto restore_sels = on_scope_end([&]{ editor.select(std::move(sels)); });
         editor.multi_select(std::bind(select_all_matches, _1, "."));
-        editor.insert(String() + key.key, InsertMode::Replace);
+        editor.insert(codepoint_to_str(key.key), InsertMode::Replace);
     });
 }
 

src/string.hh

@@ -101,6 +101,14 @@ inline String operator"" _str(const char* str, size_t)
     return String(str);
 }
 
+inline String codepoint_to_str(Codepoint cp)
+{
+    std::string str;
+    auto it = back_inserter(str);
+    utf8::dump(it, cp);
+    return String(str);
+}
+
 }
 
 namespace std