[3.13] gh-119035: Add Ctrl+← and Ctrl+→ word-skipping keybindings to new repl (GH-119248) (#119323)

add word-skipping ctrl keybindings to new repl
(cherry picked from commit 0398d93)

Co-authored-by: Alastair Stanley <alastairstanley@ntlworld.com>

Author: miss-islington

Diff for: Lib/_pyrepl/keymap.py

@@ -177,9 +177,12 @@ def _parse_key1(key, s):
             ret = key[s]
             s += 1
     if ctrl:
-        if len(ret) > 1:
-            raise KeySpecError("\\C- must be followed by a character")
-        ret = chr(ord(ret) & 0x1F)  # curses.ascii.ctrl()
+        if len(ret) == 1:
+            ret = chr(ord(ret) & 0x1F)  # curses.ascii.ctrl()
+        elif ret in {"left", "right"}:
+            ret = f"ctrl {ret}"
+        else:
+            raise KeySpecError("\\C- followed by invalid key")
     if meta:
         ret = ["\033", ret]
     else:

Diff for: Lib/_pyrepl/reader.py

@@ -136,7 +136,9 @@ def make_default_commands() -> dict[CommandName, type[Command]]:
         (r"\<up>", "up"),
         (r"\<down>", "down"),
         (r"\<left>", "left"),
+        (r"\C-\<left>", "backward-word"),
         (r"\<right>", "right"),
+        (r"\C-\<right>", "forward-word"),
         (r"\<delete>", "delete"),
         (r"\<backspace>", "backspace"),
         (r"\M-\<backspace>", "backward-kill-word"),