Add $env:__SuppressAnsiEscapeSequences to control whether to have VT escape sequence in output

[SteveL-MSFT]

PR Summary

After some discussion, we decided we want to spend more time on the design for customer facing use. Since we need this due to issues with AzDevOps pipelines having some rendering problems, we will make it an undocumented env var for now to use internally and revisit this post PS7 as part of #10811.

Introduce $env:__SuppressAnsiEscapeSequences to suppress VT escape sequences in their output. Updated Select-String, ConciseView, and Get-Error to respect this variable. Also added helper to retrieve VT escape sequences.

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  • Documentation needed
    • Issue filed: Document $OutputPreference MicrosoftDocs/PowerShell-Docs#4947
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[PaulHigin]

LGTM

[SteveL-MSFT]

The remaining CodeFactor issue is wrong. Looks like it's looking at an older version of that source file.

[SteveL-MSFT]

Remaining Codacy issues are by-design

[lzybkr]

Why not add a command line option instead?

It's somewhat common to support an option like --color [always|auto|never].

[TravisEz13]

@lzybkr This would cause this to be needed in a lot of places in testing.

[SteveL-MSFT]

@lzybkr you mean cmdline option to pwsh?

[lzybkr]

@SteveL-MSFT - exactly. There are many tools that have such an option, mostly with the same syntax and options - here's a sampling:

• ls
• fd
• git diff
• ripgrep
• exa
• lsd

[ghost]

🎉v7.0.0-preview.6 has been released which incorporates this pull request.:tada:

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• Release Notes