Pasting long line in new REPL causes text to appear after >>>

[Siecje]

Bug report

Bug description:

When I paste code that is one line and my REPL window is small the text that would not be shown because it is offscreen is displayed after pressing enter.

For example I am pasting

thread = threading.Thread(target=lambda: threading.current_thread().name == 'MainThread')

After I paste and then press enter to create the object I see

>>> read')

I can't remove the text or use the arrow keys to navigate the letters since the >>> prompt is empty.

When the window is smaller more text is shown after >>>.

>>> thread = threading.Thread(target=lambda: threading.current_thread()\
                                                                                                                        >
>>> name == 'MainThread')

CPython versions tested on:

3.13

Operating systems tested on:

macOS

Linked PRs

• gh-123177: Deactivate line wrap for Apple Terminal via scape codes in the new REPL #123267
• [3.13] gh-123177: Deactivate line wrap for Apple Terminal via scape codes in the new REPL (GH-123267) #123322
• gh-123177: Fix prompt for wrapped lines in pyrepl #123324
• [3.13] gh-123177: Fix prompt for wrapped lines in pyrepl (GH-123324) #123327

[skirpichev]

Hmm, can someone reproduce this on recent main? Is this Mac-specific? I can't reproduce this on Linux.

[pablogsal]

I cannot reproduce exactly this, but there is something weird happening with macOS terminal application (I could not reproduce this with iTerm):

Screen.Recording.2024-08-23.at.14.20.38.mov

[pablogsal]

This seems partially related to the cache but not fully. Removing the line cache shows the following problem:

Screen.Recording.2024-08-23.at.14.34.00.mov

[pablogsal]

For some reason this only happens in the terminal app and not in iterm

[pablogsal]

Another problem: seems like the cache forces lines that warp around to also start with >>> (but they should not).

[pablogsal]

@godlygeek could you take a look at this if you have some free cycles?

[Siecje]

When I type random words like that as soon as I get to the end of the line I see strange behaviour including >>> moving.

Screen.Recording.2024-08-23.at.9.39.44.AM.mov

[pablogsal]

What terminal are you using?

[pablogsal]

Can you try if #123267 fixes the other problem for you?

[Siecje]

What terminal are you using?

The default "Terminal"

[pablogsal]

Can you run echo $TERM_PROGRAM?

[Siecje]

Apple_Terminal

[godlygeek]

Seems like there's two separate issues here, one with how Apple Terminal behaves when something is written to the last column of a line, and one with the cache. I understand what's causing the cache bug, but I'm still deciding how best to fix it.