Provide a way to distinguish between terminating error vs. non-terminating error

[HemantMahawar]

Add more details later

Steps to reproduce

Expected behavior

Actual behavior

Environment data

> $PSVersionTable

[apetitjean]

That is definitely something that should be addressed! That makes just 10 years we struggle with that ;-)

[mklement0]

Related: #4292

Given the current capabilities:

• In hindsight, by inspecting $Error, I don't think there's a (straightforward) way to classify previous errors - though I'm not sure that's needed. [Update: It is needed in order to provide error type-specific coloring, for instance - see Suggestion: Add an $ErrorView option that displays concise, single-line error information and consider making that the default - default formatting of ErrorRecord #3647]

• To distinguish errors as they occur, use a Try / Catch statement: only terminating errors will trigger the Catch handler:

Note: I'm using 1 / 0 as a stand-in for a pipeline-terminating error here:

# Trigger a pipeline-terminating error; works the same with a script-terminating error (Throw).
$errCountBefore = $Error.Count
$terminatingErrorOccurred = $False
Try {
  1 / 0
}  Catch { # TRIGGERED by a TERMINATING ERROR - both pipeline-terminating and script-terminating
  # Note: To also *output* the error, use Write-Error $_, but note that this
  #       *duplicates* the automatically generated $Error entry.
  Write-Error $_
  $terminatingErrorOccurred = $True
}
if ($terminatingErrorOccurred)            { 'Terminating error occurred.' }
elseif ($Error.Count -gt $errCountBefore) { 'Non-terminating error occurred.' }

'---'

# Trigger a non-terminating error.
$errCountBefore = $Error.Count
$terminatingErrorOccurred = $False
Try {
  # A non-terminating error prints its output to the error stream,
  # irrespective of any enclosing Try/Catch handler.
  Get-Item /NoSuch
}  Catch {  # NOT triggered by a NON-TERMINATING ERROR
 $terminatingErrorOccurred = $True
}
if ($terminatingErrorOccurred)            { 'Terminating error occurred.' }
elseif ($Error.Count -gt $errCountBefore) { 'Non-terminating error occurred.' }

The above yields:

/Users/jdoe/Desktop/pg/pg1.ps1 : Attempted to divide by zero.
....
Terminating error occurred.
---
Get-Item : Cannot find path '/NoSuch' because it does not exist.
...
Non-terminating error occurred.

[joeyaiello]

@SteveL-MSFT: I want this for Functions per our discussion on critical vs error logs.

/cc @TylerLeonhardt @daxian-dbw

[SteveL-MSFT]

Dupe of #4781. Yes, this one is older, but the latter has more discussion.