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EncoderFallbackException: Unable to translate Unicode character

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
45/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
csharp
Domain
cli

Research direction

Start with the PSConsoleReadLine.WriteHistoryRange and IncrementalHistoryWrite paths shown in the exception stack trace, then reproduce the paste, cursor movement, deletion, and Enter sequence on Windows. Done means the Unicode input is handled without EncoderFallbackException and the terminal shows the expected text after deletion.

Written by the indexing model from the issue text.

Description

Needs-Triage :mag:
Prerequisites
  • Write a descriptive title.
  • Make sure you are able to repro it on the latest released version
  • Search the existing issues, especially the pinned issues.
Exception report
PS C:\Users\x> ✓ ✔ �

Oops, something went wrong.
Please report this bug with ALL the details below, including both the 'Environment' and 'Exception' sections.
Please report on GitHub: https://github.com/PowerShell/PSReadLine/issues/new?template=Bug_Report.yaml
Thank you!

### Environment
PSReadLine: 2.3.6+d2e770f93b7a53d8660a6402eb29d1ae1c35e767
PowerShell: 7.5.4
OS: Microsoft Windows 10.0.26200
BufferWidth: 378
BufferHeight: 70

Last 37 Keys:

 ✓ Spacebar ✔ Spacebar � � LeftArrow End Delete RightArrow LeftArrow Delete Enter
 Ctrl+Backspace Backspace Backspace Backspace Ctrl+Backspace Ctrl+Backspace Ctrl+Backspace Ctrl+Backspace RightArrow RightArrow Backspace c l s Enter
 ✓ Spacebar ✔ Spacebar � � LeftArrow Delete Enter


### Exception

System.Text.EncoderFallbackException: Unable to translate Unicode character \\uD83D at index 4 to specified code page.
   at System.Text.EncoderExceptionFallbackBuffer.Fallback(Char charUnknown, Int32 index)
   at System.Text.Encoding.GetBytesWithFallback(ReadOnlySpan`1 chars, Int32 originalCharsLength, Span`1 bytes, Int32 originalBytesLength, EncoderNLS encoder, Boolean throwForDestinationOverflow)
   at System.Text.Encoding.GetBytesWithFallback(Char* pOriginalChars, Int32 originalCharCount, Byte* pOriginalBytes, Int32 originalByteCount, Int32 charsConsumedSoFar, Int32 bytesWrittenSoFar, EncoderNLS encoder)
   at System.IO.StreamWriter.Flush(Boolean flushStream, Boolean flushEncoder)
   at System.IO.StreamWriter.Dispose(Boolean disposing)
   at System.IO.TextWriter.Dispose()
   at Microsoft.PowerShell.PSConsoleReadLine.<>c__DisplayClass103_0.<WriteHistoryRange>b__0()
   at Microsoft.PowerShell.PSConsoleReadLine.<>c__DisplayClass103_0.<WriteHistoryRange>b__0()
   at Microsoft.PowerShell.PSConsoleReadLine.WithHistoryFileMutexDo(Int32 timeout, Action action)
   at Microsoft.PowerShell.PSConsoleReadLine.WriteHistoryRange(Int32 start, Int32 end, Boolean overwritten)
   at Microsoft.PowerShell.PSConsoleReadLine.IncrementalHistoryWrite()
   at Microsoft.PowerShell.PSConsoleReadLine.MaybeAddToHistory(String result, List`1 edits, Int32 undoEditIndex, Boolean fromDifferentSession, Boolean fromInitialRead)
   at Microsoft.PowerShell.PSConsoleReadLine.InputLoop()
   at Microsoft.PowerShell.PSConsoleReadLine.ReadLine(Runspace runspace, EngineIntrinsics engineIntrinsics, CancellationToken cancellationToken, Nullable`1 lastRunStatus)


PS C:\Users\x> ✓ ✔ �
Screenshot

Pasting:
PS C:\Users\x> ✓ ✔ 🗸
Actually pastes:
PS C:\Users\x> ✓ ✔ 🗸�
So performing the above mentioned steps will result in the given error.
Visual Example of input:

Image

PS C:\Users\x> ✓ ✔ 🗸|�

Environment data
PS Version: 7.5.4
PS HostName: ConsoleHost (Windows Terminal)
PSReadLine Version: 2.3.6
PSReadLine EditMode: Windows
OS: 10.0.26100.1 (WinBuild.160101.0800)
BufferWidth: 340
BufferHeight: 67
Steps to reproduce

Pasting:
PS C:\Users\x> ✓ ✔ 🗸
Actually pastes:
PS C:\Users\x> ✓ ✔ 🗸�
So performing the above mentioned steps will result in the given error.
Visual Example of input:
Paste:
Image
Press [Left arrow key]:
Image
Press [delete]:
Image
Press [enter]:
Image

Expected behavior
Terminal should show:

PS C:\Users\x> ✓ ✔ 🗸
PS C:\Users\x> ✓ ✔ -> Where the last chracter is deleted

Actual behavior
Terminal shows:

PS C:\Users\x> ✓ ✔ 🗸\
PS C:\Users\x> ✓ ✔ �� -> Where the last chracter is deleted

Image
Dominant language
C#
Stars
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Forks
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PR merge metrics
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