Calling action scriptblock for registered Powershel.Exiting EngineEvent throws NullReferenceException if script block contains 'finally' block #11869
Description
Steps to reproduce
- create file
code.ps1with content:
Register-EngineEvent -SourceIdentifier Powershell.Exiting -Action {
Write-Host "Start ExitHandler"
try{
try{}
catch{}
finally{ }
}
catch{
# print all exceptions (with all inner)
# code from the book "Windows Powershell in action 3rd edition, page 534"
$ErrorRecord = $Error[0]
$out=""
$out+= $($ErrorRecord | Format-List -Property * -Force | out-string)
$out+= $($ErrorRecord.InvocationInfo | Format-List -Property * | out-string)
$Exception = $ErrorRecord.Exception
for ($depth = 0; $Exception -ne $null; $depth++)
{
$out+= $("$depth" * 80)
$out+= $($Exception | Format-List -Property * -Force | out-string)
$Exception = $Exception.InnerException
}
Write-Host "$out"
}
Write-Host "End ExitHandler"
}
exit
- Create second file
run_code.ps1with content (in the same directory):
pwsh "${PsScriptRoot}/code.ps1"
- run file
run_code.ps1
Expected behavior
User should see two printed lines
Start ExitHandler
End ExitHandler
Actual behavior
User sees exception details similar to this:
PSMessageDetails :
Exception : System.NullReferenceException: Object reference not set to an instance of an object.
at System.Management.Automation.ExceptionHandlingOps.SuspendStoppingPipeline(ExecutionContext context)
at System.Management.Automation.Interpreter.FuncCallInstruction`2.Run(InterpretedFrame frame)
at System.Management.Automation.Interpreter.EnterTryCatchFinallyInstruction.Run(InterpretedFrame frame)
at System.Management.Automation.Interpreter.EnterTryCatchFinallyInstruction.Run(InterpretedFrame frame)
TargetObject :
CategoryInfo : OperationStopped: (:) [], NullReferenceException
FullyQualifiedErrorId : System.NullReferenceException
ErrorDetails :
InvocationInfo : System.Management.Automation.InvocationInfo
ScriptStackTrace : at <ScriptBlock>, ...\code.ps1: line 7
PipelineIterationInfo : {}
MyCommand :
BoundParameters : {}
UnboundArguments : {}
ScriptLineNumber : 7
OffsetInLine : 5
HistoryId : -1
ScriptName : ...\code.ps1
Line : Write-Host "Start ExitHandler"
PositionMessage : At ...\code.ps1:7 char:5
+ Write-Host "Start ExitHandler"
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PSScriptRoot : ...
PSCommandPath : ...\code.ps1
InvocationName :
PipelineLength : 0
PipelinePosition : 0
ExpectingInput : False
CommandOrigin : Internal
DisplayScriptPosition :
00000000000000000000000000000000000000000000000000000000000000000000000000000000
Message : Object reference not set to an instance of an object.
Data : {System.Management.Automation.Interpreter.InterpretedFrameInfo}
InnerException :
TargetSite : Boolean SuspendStoppingPipeline(System.Management.Automation.ExecutionContext)
StackTrace : at System.Management.Automation.ExceptionHandlingOps.SuspendStoppingPipeline(ExecutionContext context)
at System.Management.Automation.Interpreter.FuncCallInstruction`2.Run(InterpretedFrame frame)
at System.Management.Automation.Interpreter.EnterTryCatchFinallyInstruction.Run(InterpretedFrame frame)
at System.Management.Automation.Interpreter.EnterTryCatchFinallyInstruction.Run(InterpretedFrame frame)
HelpLink :
Source : System.Management.Automation
HResult : -2147467261
Environment data
Name Value
---- -----
PSVersion 6.2.4
PSEdition Core
GitCommitId 6.2.4
OS Microsoft Windows 10.0.18362
Platform Win32NT
PSCompatibleVersions {1.0, 2.0, 3.0, 4.0…}
PSRemotingProtocolVersion 2.3
SerializationVersion 1.1.0.1
WSManStackVersion 3.0
The funny thing is that if you comment out line 6 finally{ } the code will work.
I was trying to find some more information about what kind of code can/cannot appear in Powershell.Exiting action scriptblock but did not find any restrictions etc.