Test-Error.ps1

param(
	[ValidateSet("Test-ErrorCustom","Test-ErrorCustomBroken","Test-ErrorWriteErrorThrowString","Test-ErrorWriteErrorThrowObject","Test-ErrorWriteErrorErrActionStop","Test-ErrorWriteErrorReturn","Test-ErrorWriteErrorReturnTryCatch","Test-ErrorWriteErrorErrActionStopTryCatch","Test-ErrorWriteErrorErrActionStopSimpleFunction","Test-ErrorWriteErrorErrActionStopSimpleFunctionWithERRStringConversion")] 
    [string]$testFunction,
    [ValidateSet("dollarQuestionCapture","tryCatchCapture")]
    [string]$testType,
    [string]$outputFile
)

function Test-ErrorCustom {
    [CmdletBinding()]
    Param([Parameter(Position=0,mandatory=$false)][int]$divideBy=0)

    Write-Host "Executing custom error with return"
    1/$divideBy
    if (!$?){
        $errObj = new-object System.Management.Automation.RuntimeException "Omigosh you tried to divide by 0?"
        $category = [System.Management.Automation.ErrorCategory]::NotSpecified
        $errRecord = new-object System.Management.Automation.ErrorRecord $errObj, "PathNotFound", $category, $divideBy
        $psCmdlet.WriteError($errRecord)
        return $errRecord
    }
}

function Test-ErrorCustomBroken {
    [CmdletBinding()]
    Param([Parameter(Position=0,mandatory=$false)][int]$divideBy=0)

    Write-Host "Executing broken custom error with return"
    1/$divideBy
    if (!$?){
        $errObj = new-object System.Management.Automation.ItemNotFoundException "Omigosh you tried to divide by 0?"
        $category = [This.Error.Is.NOT.Right.Because.the.Error.is.About.the.Error]::ObjectNotFound
        $errRecord = new-object System.Management.Automation.ErrorRecord $errObj, "PathNotFound", $category, $divideBy
        $psCmdlet.WriteError($errRecord)
        return $errRecord
    }
}

function Test-ErrorWriteErrorThrowString {
    # Write-Error with throw
    [CmdletBinding()]
    Param([Parameter(Position=0,mandatory=$false)][int]$divideBy=0)
    
    Write-Host "Executing Write-Error with throw (string)"
    1/$divideBy
    if (!$?){
        Write-Error "here is my error in my function"
        throw "git outta here"
    }
}

function Test-ErrorWriteErrorThrowObject {
    [CmdletBinding()]
    Param([Parameter(Position=0,mandatory=$false)][int]$divideBy=0)
    Write-Host "Executing Write-Error with throw (object)"
    1/$divideBy
    if (!$?){
        Write-Error "here is my error in my function"
        Throw [System.Management.Automation.ValidationMetadataException] "I returned an error and I'm so proud."
    }
}

function Test-ErrorWriteErrorReturn {
    [CmdletBinding()]
    Param([Parameter(Position=0,mandatory=$false)][int]$divideBy=0)

    Write-Host "Executing Write-Error with ErrorAction Stop using Try/Catch"
	1/$divideBy
    if (!$?){
        Write-error "here is my error in my function using dollarquestion and return for stdout"
        return "Hey buddy you had an error that you should check out"
    }
	write-host "We got past the error" -foregroundcolor green
}

function Test-ErrorWriteErrorReturnTryCatch {
    [CmdletBinding()]
    Param([Parameter(Position=0,mandatory=$false)][int]$divideBy=0)

    Write-Host "Executing Write-Error with ErrorAction Stop using Try/Catch"
	try {1/$divideBy}
	catch {
        Write-error "here is my error in my function using try/catch and return for stdout"
        return "Hey buddy you had an error that you should check out"
    }
	write-host "We got past the error" -foregroundcolor green
}

function Test-ErrorWriteErrorErrActionStop {
    [CmdletBinding()]
    Param([Parameter(Position=0,mandatory=$false)][int]$divideBy=0)

    Write-Host "Executing Write-Error with ErrorAction Stop"
    1/$divideBy
    if (!$?){Write-Error "here is my error in my function" -ErrorAction Stop}
}

function Test-ErrorWriteErrorErrActionStopTryCatch {
    [CmdletBinding()]
    Param([Parameter(Position=0,mandatory=$false)][int]$divideBy=0)

    Write-Host "Executing Write-Error with ErrorAction Stop using Try/Catch"
	try {1/$divideBy}
	catch {Write-error "here is my error in my function using try/catch" -ErrorAction stop}
	write-host "We got past the error" -foregroundcolor green
}

function Test-ErrorWriteErrorErrActionStopSimpleFunction {

    Write-Host "Executing non-advanced function with try/catch and terminating write-error/erroraction stop"
	try {1/0}
	catch {Write-error "here is my error in my simple, similar behaving function" -ErrorAction stop}
	write-host "We got past the error" -foregroundcolor green
}

function Test-ErrorWriteErrorErrActionStopSimpleFunctionWithERRStringConversion {    
    Write-Host "Executing non-advanced function with try/catch, error[0] conversion to string, and terminating write-error/erroraction stop"
    try {1/0}
    catch {Write-error "That really didn't work.  System Error:`r`n`t$($Error[0] | Out-String)" -ErrorAction stop}
    write-host "We got past the error" -foregroundcolor green
}

function Set-OutputTrackerObject {
    Param(
        [Parameter(Position=0,mandatory=$true)]$testFunction,
        [Parameter(Position=1,mandatory=$true)]$testType,
        [Parameter(Position=2,mandatory=$true)]$trapStatus,
        [Parameter(Position=3,mandatory=$true)]$standardOut,
        [Parameter(Position=4,mandatory=$true)]$errorStream
    )
    $trackerObject=@([pscustomobject]@{entry=$testFunction;type=$testType;successfulTrap=$trapStatus;standardOutput=$standardOut;errorStream=$errorStream})
    return $trackerObject
}

function Write-OutputTrackerObject {
    Param(
        [Parameter(Position=0,mandatory=$true)]$objectToWrite,
        [Parameter(Position=1,mandatory=$true)]$fileToWriteTo
    )
    $objectToWrite| Export-Clixml $fileToWriteTo -Force
    if (!$?){return $false}
    else {return $true}
}

$Error.Clear()
if ($output){Remove-Variable output}
$successfultrap=$false
$standardOut="null"
$errorStream=$Error.Clone()
$outputTrackerDataObject=Set-OutputTrackerObject $testFunction $testType $successfultrap $standardOut $errorStream
$writeStatus=Write-OutputTrackerObject $outputTrackerDataObject $PSScriptRoot\object$random.xml
if (!$writeStatus){throw "Could not persist object to file"}
Write-Warning "*******************************TESTING FUNCTION $testFunction using $testType ********************************** `n"
switch ($testType){
    dollarQuestionCapture{
        #NOTE: We can't do Invoke-Expression $testFunction because $? will always be true since invoke-expression actually succeeded. 
        switch ($testFunction){
            Test-ErrorCustom{$output=Test-ErrorCustom}
            Test-ErrorCustomBroken{$output=Test-ErrorCustomBroken}
            Test-ErrorWriteErrorThrowString{$output=Test-ErrorWriteErrorThrowString}
            Test-ErrorWriteErrorThrowObject{$output=Test-ErrorWriteErrorThrowObject}
            Test-ErrorWriteErrorErrActionStop{$output=Test-ErrorWriteErrorErrActionStop}
            Test-ErrorWriteErrorErrActionStopTryCatch{$output=Test-ErrorWriteErrorErrActionStopTryCatch}
            Test-ErrorWriteErrorErrActionStopSimpleFunction{$output=Test-ErrorWriteErrorErrActionStopSimpleFunction}
            Test-ErrorWriteErrorErrActionStopSimpleFunctionWithERRStringConversion{$output=Test-ErrorWriteErrorErrActionStopSimpleFunctionWithERRStringConversion}
        }
        if (!$?){
            $successfultrap=$true
            if ($output -eq $null){$standardOut="null"}
            else {$standardOut=$output}
            $errorStream=$Error.Clone()
            $outputTrackerDataObject=Set-OutputTrackerObject $testFunction $testType $successfultrap $standardOut $errorStream
            $writeStatus=Write-OutputTrackerObject $outputTrackerDataObject $outputFile
            if (!$writeStatus){throw "Could not persist object to file"}
        }
        else {
            $successfultrap=$false
            if ($output -eq $null){$standardOut="null"}
            else {$standardOut=$output}
            $errorStream=$Error.Clone()
            $outputTrackerDataObject=Set-OutputTrackerObject $testFunction $testType $successfultrap $standardOut $errorStream
            $writeStatus=Write-OutputTrackerObject $outputTrackerDataObject $outputFile
            if (!$writeStatus){throw "Could not persist object to file"}
        }
    }
    tryCatchCapture{
        try{
            switch ($testFunction){
                Test-ErrorCustom{$output=Test-ErrorCustom}
                Test-ErrorCustomBroken{$output=Test-ErrorCustomBroken}
                Test-ErrorWriteErrorThrowString{$output=Test-ErrorWriteErrorThrowString}
                Test-ErrorWriteErrorThrowObject{$output=Test-ErrorWriteErrorThrowObject}
                Test-ErrorWriteErrorErrActionStop{$output=Test-ErrorWriteErrorErrActionStop}
                Test-ErrorWriteErrorErrActionStopTryCatch{$output=Test-ErrorWriteErrorErrActionStopTryCatch}
                Test-ErrorWriteErrorErrActionStopSimpleFunction{$output=Test-ErrorWriteErrorErrActionStopSimpleFunction}
                Test-ErrorWriteErrorErrActionStopSimpleFunctionWithERRStringConversion{$output=Test-ErrorWriteErrorErrActionStopSimpleFunctionWithERRStringConversion}
            }
        }
        catch {
            $successfultrap=$true
            if ($output -eq $null){$standardOut="null"}
            else {$standardOut=$output}
            $errorStream=$Error.Clone()
            $outputTrackerDataObject=Set-OutputTrackerObject $testFunction $testType $successfultrap $standardOut $errorStream
            $writeStatus=Write-OutputTrackerObject $outputTrackerDataObject $outputFile
            if (!$writeStatus){throw "Could not persist object to file"}
        }
        if (!$successfultrap){
            $successfultrap=$false
            if ($output -eq $null){$standardOut="null"}
            else {$standardOut=$output}
            $errorStream=$Error.Clone()
            $outputTrackerDataObject=Set-OutputTrackerObject $testFunction $testType $successfultrap $standardOut $errorStream
            $writeStatus=Write-OutputTrackerObject $outputTrackerDataObject $outputFile
            if (!$writeStatus){throw "Could not persist object to file"}
        }
    }
}
Write-Host "******************************* $testFunction TESTING COMPLETE using $testType **********************************`n`n" -ForegroundColor Black -BackgroundColor White