starred/terminal
1
0
Fork 0
mirror of https://github.com/microsoft/terminal.git synced 2026-02-04 05:35:20 +00:00
Code Issues 19.0k Packages Projects Releases 20 Wiki Activity

3-line commands that scrolled the window in powershell visually duplicate if partially deleted #17451

New Issue
Closed
opened 2026-01-31 05:42:56 +00:00 by claunia · 5 comments
claunia commented 2026-01-31 05:42:56 +00:00
Owner
Copy Link

Originally created by @omgitsraven on GitHub (May 10, 2022).

Windows Terminal version

1.12.10982.0

Windows build number

10.0.19044.0

Other Software

No response

Steps to reproduce

  1. Open Windows Terminal
  2. Open a Powershell terminal
  3. Press the enter key repeatedly, until the content of the window begins to scroll (so that the active prompt is at the bottom of the window.)
  4. Type a command that wraps onto three lines, but do not hit enter. (The command doesn't have to be valid, you can just hold down the q key.)
  5. Start deleting characters with the backspace key, until the command should fit onto two lines. (Go slightly past it fitting exactly; make some empty space on the end of the second line.)

Expected Behavior

You should see a two-line-long command after your prompt.

Actual Behavior

Once you delete enough characters to fit exactly on two lines, the window scrolls up for some reason... And then, once you delete one character MORE than that, the first two lines visually mash up to create a command that appears to still be three lines long! (The command actually still runs normally, it's just very confusing to edit...)

Here is an example, where I filled the first line with as, the second line with bs, and the third line with cs, and then deleted the third line and some of the second:

Before deleting anything:
image

After pressing backspace several times:
image

Also, note that this happens in Powershell running inside Windows Terminal, but NOT when attempted in the standalone Powershell prompt.

Originally created by @omgitsraven on GitHub (May 10, 2022). ### Windows Terminal version 1.12.10982.0 ### Windows build number 10.0.19044.0 ### Other Software _No response_ ### Steps to reproduce 1. Open Windows Terminal 2. Open a Powershell terminal 3. Press the enter key repeatedly, until the content of the window begins to scroll (so that the active prompt is at the *bottom* of the window.) 4. Type a command that wraps onto *three* lines, but do *not* hit enter. (The command doesn't have to be valid, you can just hold down the `q` key.) 5. Start *deleting* characters with the backspace key, until the command should fit onto two lines. (Go slightly *past* it fitting exactly; make some empty space on the end of the second line.) ### Expected Behavior You should see a two-line-long command after your prompt. ### Actual Behavior Once you delete enough characters to fit *exactly* on two lines, the window scrolls up for some reason... And then, once you delete one character MORE than that, the first two lines visually mash up to create a command that appears to still be three lines long! (The command actually still runs normally, it's just very confusing to edit...) Here is an example, where I filled the first line with `a`s, the second line with `b`s, and the third line with `c`s, and then deleted the third line and some of the second: Before deleting anything: ![image](https://user-images.githubusercontent.com/8540042/167512931-5b61beaf-3152-499b-840b-d3992e7473cc.png) After pressing backspace several times: ![image](https://user-images.githubusercontent.com/8540042/167512952-577281d1-d81c-4ec7-adc4-9d0ab465d432.png) Also, note that this happens in Powershell running inside Windows Terminal, but NOT when attempted in the *standalone* Powershell prompt.
claunia added the Issue-BugResolution-ExternalNeeds-Tag-Fix labels 2026-01-31 05:42:56 +00:00
claunia commented 2026-01-31 05:42:57 +00:00
Author
Owner
Copy Link

@j4james commented on GitHub (May 12, 2022):

I don't know what the problem is here, but I did briefly look into it, and I just wanted to note some of the things I discovered.

  1. When the PowerShell prompt wraps at the bottom of the viewport, it's just calling SetConsoleCursorPosition to position the cursor below the viewport bottom, and that triggers a SetViewportOrigin call which pans the viewport down. As far as I can tell, that viewport movement doesn't propagate over conpty as a scroll event, so you lose any lines that scroll off the top.
  2. When the prompt has wrapped over 3 lines, and you backspace to the start of that third line, PowerShell generates a linefeed for some reason. That forces the viewport to pan down an additional row leaving an extra blank line. You can see that in conhost too - it's not just a conpty thing. As weird as that is, though, it shouldn't be causing anything to break, but I thought it might be the trigger for whatever is subsequently going wrong.

It's also worth noting that point 1 is possibly the same bug we're seeing in #10905.

@j4james commented on GitHub (May 12, 2022): I don't know what the problem is here, but I did briefly look into it, and I just wanted to note some of the things I discovered. 1. When the PowerShell prompt wraps at the bottom of the viewport, it's just calling `SetConsoleCursorPosition` to position the cursor below the viewport bottom, and that triggers a `SetViewportOrigin` call which pans the viewport down. As far as I can tell, that viewport movement doesn't propagate over conpty as a scroll event, so you lose any lines that scroll off the top. 2. When the prompt has wrapped over 3 lines, and you backspace to the start of that third line, PowerShell generates a linefeed for some reason. That forces the viewport to pan down an additional row leaving an extra blank line. You can see that in conhost too - it's not just a conpty thing. As weird as that is, though, it shouldn't be causing anything to break, but I thought it might be the trigger for whatever is subsequently going wrong. It's also worth noting that point 1 is possibly the same bug we're seeing in #10905.
claunia commented 2026-01-31 05:42:57 +00:00
Author
Owner
Copy Link

@zadjii-msft commented on GitHub (May 16, 2022):

Oh, that does sound familiar, yea. @omgitsraven I wonder if an updated PsReadline might just fix this for you/?

@zadjii-msft commented on GitHub (May 16, 2022): Oh, that does sound familiar, yea. @omgitsraven I wonder if an updated PsReadline might just fix this for you/?
claunia commented 2026-01-31 05:42:57 +00:00
Author
Owner
Copy Link

@omgitsraven commented on GitHub (May 16, 2022):

Updating PSReadLine to 2.2.5 has fixed it!! Thank you :)

Does that mean I should close this issue then, if that fix will work its way to everyone eventually?

@omgitsraven commented on GitHub (May 16, 2022): Updating PSReadLine to 2.2.5 has fixed it!! Thank you :) Does that mean I should close this issue then, if that fix will work its way to everyone eventually?
claunia commented 2026-01-31 05:42:57 +00:00
Author
Owner
Copy Link

@zadjii-msft commented on GitHub (May 16, 2022):

Yea, we can close this out as /dup https://github.com/PowerShell/PSReadLine/issues/724

@zadjii-msft commented on GitHub (May 16, 2022): Yea, we can close this out as /dup https://github.com/PowerShell/PSReadLine/issues/724
claunia commented 2026-01-31 05:42:57 +00:00
Author
Owner
Copy Link

@ghost commented on GitHub (May 16, 2022):

Hi! We've identified this issue as a duplicate of one that exists on somebody else's Issue Tracker. Please make sure you subscribe to the referenced external issue for future updates. Thanks for your report!

@ghost commented on GitHub (May 16, 2022): Hi! We've identified this issue as a duplicate of one that exists on somebody else's Issue Tracker. Please make sure you subscribe to the referenced external issue for future updates. Thanks for your report!
Sign in to join this conversation.
No Branch/Tag Specified
Branches Tags
Labels
Clear labels
⛺ Reserved
A11yCO
A11yMAS
A11ySev1
A11ySev2
A11ySev3
A11yTTValidated
A11yUsable
A11yVoiceAccess
A11yWCAG
Area-Accessibility
Area-AtlasEngine
Area-AzureShell
Area-Build
Area-Build
Area-Chat
Area-CmdPal
Area-CodeHealth
Area-Commandline
Area-CookedRead
Area-DefApp
Area-Extensibility
Area-Fonts
Area-GroupPolicy
Area-i18n
Area-Input
Area-Interaction
Area-Interop
Area-Localization
Area-Output
Area-Performance
Area-Portable
Area-Quality
Area-Remoting
Area-Rendering
Area-Schema
Area-Server
Area-Settings
Area-SettingsUI
Area-ShellExtension
Area-ShellExtension
Area-ShellExtension
Area-Suggestions
Area-Suggestions
Area-TerminalConnection
Area-TerminalControl
Area-Theming
Area-UserInterface
Area-VT
Area-Windowing
Area-WPFControl
AutoMerge
Blocking-Ingestion
Culprit-Centennial
Culprit-WinUI
Disability-All
Disability-Blind
Disability-LowVision
Disability-Mobility
External-Blocked-WinUI3
Fixed
Gathering-Data
good first issue
HCL-E+D
HCL-WindowsTerminal
Help Wanted
Impact-Compatibility
Impact-Compliance
Impact-Correctness
Impact-Visual
In-PR
InclusionBacklog
InclusionBacklog-Windows TerminalWin32
InclusionCommitted-202206
Issue-Bug
Issue-Docs
Issue-Feature
Issue-Feature
Issue-Question
Issue-Samples
Issue-Scenario
Issue-Task
Needs-Attention
Needs-Author-Feedback
Needs-Bisect
Needs-Discussion
Needs-Repro
Needs-Tag-Fix
Needs-Tag-Fix
Needs-Triage
No-Recent-Activity
Priority-0
Priority-1
Priority-2
Priority-3
Product-Cmd.exe
Product-Colortool
Product-Colortool
Product-Colortool
Product-Conhost
Product-Conpty
Product-Meta
Product-Powershell
Product-Terminal
Product-WSL
pull-request
Mirrored from GitHub Pull Request
 Resolution-Answered
Resolution-By-Design
Resolution-Duplicate
Resolution-External
Resolution-Fix-Available
Resolution-Fix-Committed
Resolution-No-Repro
Resolution-Won't-Fix
Severity-Blocking
Severity-Crash
Severity-DataLoss
spam
this-will-be-a-breaking-change
Tracking-External
WindowsTerminal_Win32
Work-Item
zAskModeBug
zInbox-Bug
No Label Issue-Bug Needs-Tag-Fix Resolution-External
Milestone
No items
No Milestone
Projects
Clear projects
No project
Assignees
Clear assignees
claunia
No Assignees
1 Participants
Notifications
Due Date
No due date set.
Dependencies

No dependencies set.

Reference: starred/terminal#17451
Delete Branch "%!s()"

Deleting a branch is permanent. Although the deleted branch may continue to exist for a short time before it actually gets removed, it CANNOT be undone in most cases. Continue?