You can input multiline text in TextArea when multiline=False

[eight04]

The app:

from prompt_toolkit import Application
from prompt_toolkit.buffer import Buffer
from prompt_toolkit.layout.containers import Window, HSplit
from prompt_toolkit.layout.controls import BufferControl
from prompt_toolkit.layout.layout import Layout

from prompt_toolkit.key_binding import KeyBindings
from prompt_toolkit.widgets import TextArea

kb = KeyBindings()

@kb.add('c-q')
def exit_(event):
  event.app.exit()

buffer1 = Buffer()  # Editable buffer.

root_container = HSplit([
  TextArea(
    prompt='Type something: ',
    multiline=False,
    wrap_lines=False,
    accept_handler=lambda buff: buffer1.insert_text(f"accept_handler called: {buff.text}\n"),
  ),
  Window(height=1, char='-'),
  Window(content=BufferControl(buffer=buffer1)),
])

layout = Layout(root_container)

app = Application(key_bindings=kb, layout=layout, full_screen=True)
app.run()

When multiline=False, pressing enter should trigger accept_handler.

However, when pasting multi-line text to the console, TextArea draws a new line then scroll down. In this case, accept_handler won't be triggered.

Another way to trigger this bug is to type very fast when the computer is slow. I guess it works similarly as copy-pasting.

Windows 10
prompt_toolkit 3.0.47
cmd.exe + Windows Terminal

[eight04]

It seems that the problem is: there is no "paste" event on Windows, and prompt-toolkit will try to guess a paste event when getting multiline text:

python-prompt-toolkit/src/prompt_toolkit/input/win32.py

Line 260 in 6695411

if self.recognize_paste and self._is_paste(all_keys):

However, since it is just a guess, it is not reliable. When the app is slow responding and the user presses enter multiple times, these chars will be treated as a paste event.

To avoid this behavior, add this line after creating the app:

app.input.console_input_reader.recognize_paste = False

1. I suggest documenting this behavior.
2. We should handle the paste event better. Since pasting multiline text into a single-line prompt doesn't really make sense, we can reject the paste event and re-feed those keys into input. On vt100, it should throw or replace \n with a space.