Merge pull request #447 from python-cmd2/pyreadline

Corrected how we force a redisplay in pyreadline

Author: tleonhardt

cmd2/rl_utils.py

@@ -75,22 +75,24 @@ def pyreadline_remove_history_item(pos: int) -> None:
         readline_lib = ctypes.CDLL(readline.__file__)
 
 
+# noinspection PyProtectedMember
 def rl_force_redisplay() -> None:
     """
-    Causes readline to redraw prompt and input line
+    Causes readline to display the prompt and input text wherever the cursor is and start
+    reading input from this location. This is the proper way to restore the input line after
+    printing to the screen
     """
     if not sys.stdout.isatty():
         return
 
     if rl_type == RlType.GNU:  # pragma: no cover
-        # rl_forced_update_display() is the proper way to redraw the prompt and line, but we
-        # have to use ctypes to do it since Python's readline API does not wrap the function
         readline_lib.rl_forced_update_display()
 
         # After manually updating the display, readline asks that rl_display_fixed be set to 1 for efficiency
         display_fixed = ctypes.c_int.in_dll(readline_lib, "rl_display_fixed")
         display_fixed.value = 1
 
     elif rl_type == RlType.PYREADLINE:  # pragma: no cover
-        # noinspection PyProtectedMember
+        # Call _print_prompt() first to set the new location of the prompt
         readline.rl.mode._print_prompt()
+        readline.rl.mode._update_line()