microsoft/Terminal

Alternate console buffers of different sizes confuse ConPTY (and therefore Windows Terminal)

Open

#4,389 opened on Jan 28, 2020

View on GitHub
 (2 comments) (0 reactions) (0 assignees)C++ (3,212 forks)batch import
Area-OutputArea-RenderingHelp WantedIssue-BugPriority-2Product-Conpty

Repository metrics

Stars
 (35,764 stars)
PR merge metrics
 (Avg merge 27d 19h) (24 merged PRs in 30d)

Description

Environment

Microsoft Windows [Version 10.0.18362.535]
Version: 0.8.10261.0

Steps to reproduce

  1. Open a TUI application in Windows Terminal.
  2. Resize the Terminal Window
  3. Close the TUI application

The resulting terminal window acts like it is the original size before resizing, but the resized area remains visible.

For reference, the TUI application I was testing is a command line 2048 game: https://github.com/jwlodek/py_cui_2048 It can be installed with pip for python3:

pip install py_cui_2048
py2048

Expected behavior

When performing the same steps in cmd the terminal is resized back to its original size after resize and TUI application closed. This is also the case for a standalone powershell window.

Actual behavior

The window does seem to internally resize, but the extra space is still drawn. Please see video below for visual example:

TUIResizeBug

Contributor guide

Research direction
Investigate how ConPTY handles alternate screen buffer resizing and trace the event path when a TUI application exits after window resize.
Tech stack
cpp
Domain
backend
Issue type
Bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
3
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
Half day
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
GitC++
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
60