Window Resizing Causes Duplicate Session History

[Connor-McMillin]

Describe the bug

When the terminal is resized while copilot cli is running it produces duplicate output to the session history. The duplication happens for every resizing event. So for example if the terminal starts maximized and then it gets restored down and maximized again there will now be 3 copies of the session history (1 for the original first printing, 1 for sizing down, and 1 for sizing back up). This makes it very hard to see previous answers if you've done any screen resizing while in the middle of a copilot session which happens often for me

Affected version

GitHub Copilot CLI 0.0.420

Steps to reproduce the behavior

1. Launch copilot
2. Resize the screen
3. Scroll up to see duplicate output
4. You can repeat 2 and 3 any number of times to continue seeing additional duplicate output

Initial Copilot load (no duplication)

Screen resized once and we scroll up to see the original output is now duplicated once for a total of 2 sets of output

Screen resized 2 more times (total of 3 times) and scroll up to see the original output is now seen 4 times (1 original + 3 total resizes)

Windows Terminal repro (3 resizes)

Expected behavior

Screen resize should not change or add to the contents of the session history. It should only reformat the history to fit the new terminal size

Additional context

• Logs: process-1772547539465-44208.log
• CPU: x86_64
• OS: Windows 10
• Terminal: Windows Console Host, also repro'ed on Windows Terminal

[devm33]

This is unfortunately an unavoidable limitation of running in the main scrollback buffer. We are currently working on running in the alt-screen buffer which solves this problems and many others. You can try it with --alt-screen (which will be persisted) Would love to get your feedback!