Move control character escaping responsibility to the terminal UI

Fix atom text at display time, allow tabs/eol/etc... in display
atoms and escape them just-in-time

Fixes #4293

src/client.cc

@@ -107,8 +107,7 @@ bool Client::process_pending_inputs()
         catch (Kakoune::runtime_error& error)
         {
             write_to_debug_buffer(format("Error: {}", error.what()));
-            context().print_status({ fix_atom_text(error.what().str()),
+            context().print_status({error.what().str(), context().faces()["Error"] });
-                                     context().faces()["Error"] });
             context().hooks().run_hook(Hook::RuntimeError, error.what(), context());
         }
     }

src/client_manager.cc

@@ -74,8 +74,7 @@ Client* ClientManager::create_client(std::unique_ptr<UserInterface>&& ui, int pi
     }
     catch (Kakoune::runtime_error& error)
     {
-        client->context().print_status({ fix_atom_text(error.what().str()),
+        client->context().print_status({error.what().str(), client->context().faces()["Error"]});
-                                         client->context().faces()["Error"] });
         client->context().hooks().run_hook(Hook::RuntimeError, error.what(),
                                            client->context());
     }

src/commands.cc

@@ -1359,13 +1359,12 @@ const CommandDesc echo_cmd = {
         if (auto filename = parser.get_switch("to-file"))
             return write_to_file(*filename, message);
 
-        message = fix_atom_text(message);
         if (parser.get_switch("debug"))
             write_to_debug_buffer(message);
         else if (parser.get_switch("markup"))
             context.print_status(parse_display_line(message, context.faces()));
         else
-            context.print_status({replace(message, '\t', ' '), context.faces()["StatusLine"]});
+            context.print_status({message, context.faces()["StatusLine"]});
     }
 };
 
@@ -2161,7 +2160,7 @@ const CommandDesc prompt_cmd = {
                 }
                 catch (Kakoune::runtime_error& error)
                 {
-                    context.print_status({fix_atom_text(error.what()), context.faces()["Error"]});
+                    context.print_status({error.what().str(), context.faces()["Error"]});
                     context.hooks().run_hook(Hook::RuntimeError, error.what(), context);
                 }
             });
@@ -2542,7 +2541,7 @@ const CommandDesc fail_cmd = {
     CommandCompleter{},
     [](const ParametersParser& parser, Context&, const ShellContext&)
     {
-        throw failure{fix_atom_text(join(parser, " "))};
+        throw failure{join(parser, " ")};
     }
 };
 

src/display_buffer.cc

@@ -332,22 +332,4 @@ DisplayLine parse_display_line(StringView line, const FaceRegistry& faces, const
     return res;
 }
 
-String fix_atom_text(StringView str)
-{
-    String res;
-    auto pos = str.begin();
-    for (auto it = str.begin(), end = str.end(); it != end; ++it)
-    {
-        char c = *it;
-        if (c >= 0 and c <= 0x1F)
-        {
-            res += StringView{pos, it};
-            res += String{Codepoint{(uint32_t)(0x2400 + c)}};
-            pos = it+1;
-        }
-    }
-    res += StringView{pos, str.end()};
-    return res;
-}
-
 }

src/display_buffer.hh

@@ -156,7 +156,6 @@ private:
 using DisplayLineList = Vector<DisplayLine>;
 class FaceRegistry;
 
-String fix_atom_text(StringView str);
 DisplayLine parse_display_line(StringView line, const FaceRegistry& faces, const HashMap<String, DisplayLine>& builtins = {});
 
 class DisplayBuffer : public UseMemoryDomain<MemoryDomain::Display>

src/input_handler.cc

@@ -575,12 +575,12 @@ public:
         const Face cursor_face = m_faces["StatusCursor"];
 
         if (m_cursor_pos == str.char_length())
-            return DisplayLine{{ { fix_atom_text(str.substr(m_display_pos, width-1)), line_face },
+            return DisplayLine{{ { str.substr(m_display_pos, width-1).str(), line_face },
                                  { " "_str, cursor_face} } };
         else
-            return DisplayLine({ { fix_atom_text(str.substr(m_display_pos, m_cursor_pos - m_display_pos)), line_face },
+            return DisplayLine({ { str.substr(m_display_pos, m_cursor_pos - m_display_pos).str(), line_face },
-                                 { fix_atom_text(str.substr(m_cursor_pos,1)), cursor_face },
+                                 { str.substr(m_cursor_pos,1).str(), cursor_face },
-                                 { fix_atom_text(str.substr(m_cursor_pos+1, width - m_cursor_pos + m_display_pos - 1)), line_face } });
+                                 { str.substr(m_cursor_pos+1, width - m_cursor_pos + m_display_pos - 1).str(), line_face } });
     }
 private:
     CharCount  m_cursor_pos = 0;

src/normal.cc

@@ -966,7 +966,7 @@ void use_selection_as_search_pattern(Context& context, NormalParams params)
     const char reg = to_lower(params.reg ? params.reg : '/');
 
     context.print_status({
-        format("register '{}' set to '{}'", reg, fix_atom_text(pattern)),
+        format("register '{}' set to '{}'", reg, pattern),
         context.faces()["Information"] });
 
     RegisterManager::instance()[reg].set(context, {pattern});

src/terminal_ui.cc

@@ -23,6 +23,24 @@ namespace Kakoune
 using std::min;
 using std::max;
 
+static String fix_atom_text(StringView str)
+{
+    String res;
+    auto pos = str.begin();
+    for (auto it = str.begin(), end = str.end(); it != end; ++it)
+    {
+        char c = *it;
+        if (c >= 0 and c <= 0x1F)
+        {
+            res += StringView{pos, it};
+            res += String{Codepoint{(uint32_t)(0x2400 + c)}};
+            pos = it+1;
+        }
+    }
+    res += StringView{pos, str.end()};
+    return res;
+}
+
 struct TerminalUI::Window::Line
 {
     struct Atom
@@ -58,11 +76,11 @@ struct TerminalUI::Window::Line
     {
         if (not atoms.empty() and atoms.back().face == face and (atoms.back().skip == 0 or text.empty()))
         {
-            atoms.back().text += text;
+            atoms.back().text += fix_atom_text(text);
             atoms.back().skip += skip;
         }
         else
-            atoms.push_back({text.str(), skip, face});
+            atoms.push_back({fix_atom_text(text), skip, face});
     }
 
     void resize(ColumnCount width)