fish_key_reader: ignore sentinel key

Also, move the undo grouping for paste to the right place.

src/bin/fish_key_reader.rs

@@ -20,7 +20,7 @@
     eprintf, fprintf,
     input::input_terminfo_get_name,
     input_common::{CharEvent, InputEventQueue, InputEventQueuer},
-    key::Key,
+    key::{self, Key},
     panic::panic_handler,
     print_help::print_help,
     printf,
@@ -117,6 +117,9 @@ fn process_input(continuous_mode: bool) -> i32 {
             continue;
         };
         let c = kevt.key.codepoint;
+        if c == key::Invalid {
+            continue;
+        }
         bind_chars.push((kevt.key, kevt.seq));
         output_bind_command(&mut bind_chars);
         if output_matching_key_name(&mut recent_chars1, c) {

src/input.rs

@@ -456,11 +456,13 @@ fn uvar_change_notified(&mut self) {
 
     fn paste_start_buffering(&mut self) {
         self.paste_buffer = Some(vec![]);
+        self.push_front(CharEvent::from_readline(ReadlineCmd::BeginUndoGroup));
     }
     fn paste_is_buffering(&self) -> bool {
         self.paste_buffer.is_some()
     }
     fn paste_commit(&mut self) {
+        self.push_front(CharEvent::from_readline(ReadlineCmd::EndUndoGroup));
         let buffer = self.paste_buffer.take().unwrap();
         self.push_front(CharEvent::Command(sprintf!(
             "__fish_paste %s",

src/input_common.rs

@@ -869,11 +869,9 @@ fn parse_csi(&mut self, buffer: &mut Vec<u8>) -> Option<Key> {
                 } // rxvt style
                 200 => {
                     self.paste_start_buffering();
-                    self.push_front(CharEvent::from_readline(ReadlineCmd::BeginUndoGroup));
                     return Some(Key::from_raw(key::Invalid));
                 }
                 201 => {
-                    self.push_front(CharEvent::from_readline(ReadlineCmd::EndUndoGroup));
                     self.paste_commit();
                     return Some(Key::from_raw(key::Invalid));
                 }

src/key.rs

@@ -22,7 +22,7 @@
 pub(crate) const Insert: char = '\u{F50c}';
 pub(crate) const Tab: char = '\u{F50d}';
 pub(crate) const Space: char = '\u{F50e}';
-pub(crate) const Invalid: char = '\u{F50f}';
+pub const Invalid: char = '\u{F50f}';
 pub(crate) fn function_key(n: u32) -> char {
     assert!((1..=12).contains(&n));
     char::from_u32(u32::from(Invalid) + n).unwrap()