Reset the buffer, unless the accept_handler returns True (keep_text).

This is a backwards incompatible change.

Author: jonathanslenders

prompt_toolkit/buffer.py

@@ -134,7 +134,6 @@ class Buffer(object):
  current input line and implements all text manipulations on top of it. It
  also implements the history, undo stack and the completion state.
 
- :param eventloop: :class:`~prompt_toolkit.eventloop.EventLoop` instance.
  :param completer: :class:`~prompt_toolkit.completion.Completer` instance.
  :param history: :class:`~prompt_toolkit.history.History` instance.
  :param tempfile_suffix: The tempfile suffix (extension) to be used for the
@@ -144,8 +143,14 @@ class Buffer(object):
  :param name: Name for this buffer. E.g. DEFAULT_BUFFER. This is mostly
  useful for key bindings where we sometimes prefer to refer to a buffer
  by their name instead of by reference.
- :param accept_handler: Callback that takes this buffer as input. Called when
- the buffer input is accepted. (Usually when the user presses `enter`.)
+ :param accept_handler: Called when the buffer input is accepted. (Usually
+ when the user presses `enter`.) The accept handler receives this
+ `Buffer` as input and should return True when the buffer text should be
+ kept instead of calling reset.
+
+ In case of a `PromptSession` for instance, we want to keep the text,
+ because we will exit the application, and only reset it during the next
+ run.
 
  Events:
 
@@ -1608,10 +1613,16 @@ def validate_and_handle(self):
 
  # When the validation succeeded, accept the input.
  if valid:
- if self.accept_handler:
- self.accept_handler(self)
  self.append_to_history()
 
+ if self.accept_handler:
+ keep_text = self.accept_handler(self)
+ else:
+ keep_text = False
+
+ if not keep_text:
+ self.reset()
+
 
 def _only_one_at_a_time(coroutine):
  """

prompt_toolkit/shortcuts/prompt.py

@@ -338,6 +338,7 @@ def accept(buff):
  """ Accept the content of the default buffer. This is called when
  the validation succeeds. """
  self.app.exit(result=buff.document.text)
+ return True # Keep text, we call 'reset' later on.
 
  return Buffer(
  name=DEFAULT_BUFFER,