Expected path System.Collections.Hashtable to exist, but it did not exist.

[riosengineer]

Hey all,

Looking for some guidance or a solution. I'm a bit stuck. My test seems to work fine but it seems to give this error even though my tests pass. I'm using Pester v5 in an Azure DevOps pipeline with a PowerShell task.

I'm essentially collecting all files in a specific path, then joining these to create an array with a list of file paths to run a 'Test-Path' / Should -Exist test.

Starting discovery in 1 files.
Discovery found 25 tests in 326ms.
Running tests.
##[error] [-] .tests file. should exist 110ms (86ms|24ms)
##[error]  Expected path System.Collections.Hashtable to exist, but it did not exist.
##[error]  at $_ | Should -Exist, /home/vsts/work/1/s/pipelines/.tests/pester/tests.ps1:17
##[error]  at <ScriptBlock>, /home/vsts/work/1/s/pipelines/.tests/pester/tests.ps1:17
Tests completed in 1.19s
Tests Passed: 24, Failed: 1, Skipped: 0 NotRun: 0

##[error]PowerShell exited with code '1'.

My test:

BeforeDiscovery {
    # Change the current directory to the Bicep module folder
    Set-Location -Path "/modules"
    # Define the module and test paths
    $testPath = "/home/vsts/work/1/s/modules/.tests"
    $moduleFiles = Get-ChildItem -Filter *.bicep

    foreach ($moduleFile in $moduleFiles) {
    $testFile = Join-Path $testPath ($moduleFile.BaseName + ".tests.bicep")
    $testFiles = @($testFiles) + @($testFile)
    }
}

Describe "test file" -ForEach $testFiles {
    # Check if a corresponding .tests.bicep file exists for each .bicep module file
    It "$_ should exist" {
        $_ | Should -Exist 
    }
}

It is running the tests successfully. It's like it's adding an extra Should -Exist that I can't understand currently. If I print the $testFiles out to Write-Host it all looks as expected.

What am I missing here?

Thank you!

[fflaten]

Hi. $testFiles = @($testFiles) + @($testFile) adds a null-element at the start of your array due to $testFiles being undefined on the first foreach-iteration. The test generated for the $null-element has $_ set to an empty hashtable atm. Related #2320.

To avoid the null-element, you can either:

• Declare $testFiles = @() before the loop
• Or avoid the array merging in the first place. It is inefficient anyways. Try:

    $testFiles = foreach ($moduleFile in $moduleFiles) {
        Join-Path $testPath ($moduleFile.BaseName + '.tests.bicep')
    }

[riosengineer]

Hey @fflaten. Thank you for this - your efficiency fix worked a treat and all is well. Moreover, I learnt something. I appreciate you taking the time to help.