Space character does not appear in VS Code integrated terminal starting from VS Code 1.110

[kimadeline]

Have you checked closed issues? (https://github.com/Textualize/textual/issues?q=is%3Aissue+is%3Aclosed) yes

Have you checked against the most recent version of Textual? (https://pypi.org/search/?q=textual) yes

The bug

Textual 8.0.2, Python 3.12

Given the following code:

from textual.app import App
from textual.widgets import Input


class TestApp(App):
    def compose(self):
        yield Input(placeholder="Type here...")

if __name__ == "__main__":
    app = TestApp()
    app.run()

When I press the spacebar the space character does not get displayed when running inside the VS Code integrated terminal:

test.mov

It works if I disable the terminal.integrated.enableKittyKeyboardProtocol setting in VS Code. This started happening in VS Code version 1.110 (release notes) which was just released with additional Kitty support.

It might be related to #6074 as #6074 (comment) mentions issues with the space character as well.

[github-actions]

We found the following entries in the FAQ which you may find helpful:

• Why doesn't Textual look good on macOS?
• How do I pass arguments to an app?
• How can I set a translucent app background?
• Does Textual support images?

Feel free to close this issue if you found an answer in the FAQ. Otherwise, please give us a little time to review.

This project is developed and maintained by Will McGugan. Consider sponsoring Will's work on this project (and others).

This is an automated reply, generated by FAQtory

[TomJGooding]

Could you try running your test with TEXTUAL_DEBUG=1 python repro_6408.py and paste the resulting log from keys.log here?

[kimadeline]

Here you go, I typed test abc and then killed the terminal:

---
FEED '\x1b[I'
character='\x1b'
sequence='\x1b['
sequence='\x1b[I'
AppFocus()
FEED '\x1b[?2026;2$y\x1b[?2048;0$y'
character='\x1b'
sequence='\x1b['
sequence='\x1b[?'
sequence='\x1b[?2'
sequence='\x1b[?20'
sequence='\x1b[?202'
sequence='\x1b[?2026'
sequence='\x1b[?2026;'
sequence='\x1b[?2026;2'
sequence='\x1b[?2026;2$'
sequence='\x1b[?2026;2$y'
TerminalSupportsSynchronizedOutput()
character='\x1b'
sequence='\x1b['
sequence='\x1b[?'
sequence='\x1b[?2'
sequence='\x1b[?20'
sequence='\x1b[?204'
sequence='\x1b[?2048'
sequence='\x1b[?2048;'
sequence='\x1b[?2048;0'
sequence='\x1b[?2048;0$'
sequence='\x1b[?2048;0$y'
InBandWindowResize(supported=False, enabled=False)
FEED 't'
character='t'
Key(key='t', character='t', name='t', is_printable=True)
FEED 'e'
character='e'
Key(key='e', character='e', name='e', is_printable=True)
FEED 's'
character='s'
Key(key='s', character='s', name='s', is_printable=True)
FEED 't'
character='t'
Key(key='t', character='t', name='t', is_printable=True)
FEED '\x1b[32u'
character='\x1b'
sequence='\x1b['
sequence='\x1b[3'
sequence='\x1b[32'
sequence='\x1b[32u'
Key(key='space', character=None, name='space', is_printable=False)
FEED 'a'
character='a'
Key(key='a', character='a', name='a', is_printable=True)
FEED 'b'
character='b'
Key(key='b', character='b', name='b', is_printable=True)
FEED 'c'
character='c'
Key(key='c', character='c', name='c', is_printable=True)

[TomJGooding]

It looks like VS Code is reporting space as a CSI u escape code. I might be wrong, but that isn't correct from my understanding of the Kitty keyboard spec: https://sw.kovidgoyal.net/kitty/keyboard-protocol/#disambiguate-escape-codes Checking other terminals which support this protocol, space is reported as plain text:

FEED ' '
character=' '
Key(key='space', character=' ', name='space', is_printable=True)

[kimadeline]

Kitty keyboard spec: https://sw.kovidgoyal.net/kitty/keyboard-protocol/#disambiguate-escape-codes
Checking other terminals which support this protocol, space is reported as plain text

Is that because these other terminals still report legacy codes while VS Code only reports the "new" ones? Or are you saying that space should not be included in the list of keys covered by the CSI u encoding? The table further down that same page at https://sw.kovidgoyal.net/kitty/keyboard-protocol/#id7 mentions space (and #6074 (comment) as well), but I don't know what that means in terms of support.

[TomJGooding]

Based on this sentence from the Disambiguate escape codes section:

With this flag turned on, all key events that do not generate text are represented in one of the following two forms [emphasis mine]

My understanding is that space should not be reported with CSI u encoding.

The comment you mention in issue #6074 is about other progressive enhancements so isn't really relevant here.

[mdrxy]

Same, makes our TUI totally unusable

[TomJGooding]

Fixed upstream in xtermjs which presumably should be included in the next version of VS Code:

• Fix kitty keyboard disambiguate mode for space, enter, tab, backspace xtermjs/xterm.js#5752

[willmcgugan]

Thanks @TomJGooding Looks like this is an upstream issue. I'll keep the issue open until VSCode gets the update.