Can't paste a comment (`#`) after a pipe (`|`) and a newline

Prerequisites

• Write a descriptive title.
• Make sure you are able to repro it on the latest released version
• Search the existing issues.
• Refer to the FAQ.
• Refer to Differences between Windows PowerShell 5.1 and PowerShell.

Steps to reproduce

Paste the following 3 lines into PowerShell (same for Windows PowerShell and VS Code):

1..3 |
# I do 't expect an error here
ForEach-Object { $_ }

Expected behavior

No errors, the commented line (# ...) to be neglected. Similar to putting the comment directly after the pipe character:

1..3 | # I don 't expect an error here
ForEach-Object { $_ }

Actual behavior

Error

Error details

>> # I don 't expect an error here
ParserError:
Line |
   1 |  1..3 |
     |        ~
     | An empty pipe element is not allowed.

Environment data

Name                           Value
----                           -----
PSVersion                      7.2.6
PSEdition                      Core
GitCommitId                    7.2.6
OS                             Microsoft Windows 10.0.22000
Platform                       Win32NT
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0…}
PSRemotingProtocolVersion      2.3
SerializationVersion           1.1.0.1
WSManStackVersion              3.0

Visuals

[mklement0]

Indeed this relates to the specific pasting method being employed: simulated typing (which breaks) vs. pasting the multi-line string as a whole, and the issue is being tracked in:

• https://github.com/PowerShell/PSReadLine/issues/579
  • Pasting works as intended with <kbd>Ctrl-V</kbd>, but not with right-clicking.
• The solution for Unix terminals will be to use paste bracketing:
  • https://github.com/PowerShell/PSReadLine/issues/1471

To recap briefly:

• On Windows, you can avoid the issue by using <kbd>Ctrl-V</kbd> for pasting; a fix being discussed for right-clicking - should it ever be implemented - would have to guess what constitutes a single paste action based on which simulated keystrokes occur in rapid succession.
• On Unix-like platforms: I think we’ll have to wait for PSReadLine to support paste bracketing (at least in my macOS terminals I currently see the problem).

[mklement0]

As an aside: It is a separate issue, but it is curious that parsing stops after the comment line and considers the statement complete, given that it would make more sense to keep reading, based on the pending |.

A more obvious example would be to try to paste the following (PS Core now allows placing the | on the next line):

# Breaks when pasted with right-clicking on Windows and in Unix terminals
1..3
  | Write-Output