reader: Add delete-or-exit bind function

This is an important binding and should therefore be in C++.

src/input.cpp

@@ -132,6 +132,7 @@ static const input_function_metadata_t input_function_metadata[] = {
     {readline_cmd_t::reverse_repeat_jump, L"repeat-jump-reverse"},
     {readline_cmd_t::func_and, L"and"},
     {readline_cmd_t::expand_abbr, L"expand-abbr"},
+    {readline_cmd_t::delete_or_exit, L"delete-or-exit"},
     {readline_cmd_t::cancel, L"cancel"}};
 
 static_assert(sizeof(input_function_metadata) / sizeof(input_function_metadata[0]) ==

src/input_common.h

@@ -66,6 +66,7 @@ enum class readline_cmd_t {
     backward_jump_till,
     func_and,
     expand_abbr,
+    delete_or_exit,
     cancel,
     repeat_jump,
     // NOTE: This one has to be last.

src/reader.cpp

@@ -1010,6 +1010,7 @@ static bool command_ends_paging(readline_cmd_t c, bool focused_on_search_field)
         case rl::history_token_search_backward:
         case rl::history_token_search_forward:
         case rl::accept_autosuggestion:
+        case rl::delete_or_exit:
         case rl::cancel: {
             // These commands always end paging.
             return true;
@@ -2456,6 +2457,17 @@ void reader_data_t::handle_readline_command(readline_cmd_t c, readline_loop_stat
             reader_repaint_needed();
             break;
         }
+        case rl::delete_or_exit: {
+            if (!command_line.text.empty()) {
+                command_line.position = 0;
+                command_line.text = L"";
+                update_buff_pos(&command_line, 0);
+                reader_repaint_needed();
+            } else {
+                reader_set_end_loop(true);
+            }
+            break;
+        }
         case rl::cancel: {
             // The only thing we can cancel right now is paging, which we handled up above.
             break;