Template placeholders not expanded the same way as in pester itself

[Christian Sandfeld]

There is a mismatch between how placeholders are expanded in the "Pester Tests" (vscode-adapter) extension, and how they are expanded in Pester. I would expect them to be expanded the same by both.

As an example these tests ...

Template.tests.ps1

BeforeDiscovery {
    $arrayOfHashtables = @(
        @{ Emoji = '🌵' ; Description = 'cactus' }
        @{ Emoji = '🦒' ; Description = 'giraffe' }
        @{ Emoji = '🍎' ; Description = 'apple' }
        @{ Emoji = '🐧' ; Description = 'penguin' }
        @{ Emoji = '😊' ; Description = 'smiling face with smiling eyes' }
    )

    $arrayOfObjects = @(
        [pscustomobject]@{ Emoji = '🌵' ; Description = 'cactus' }
        [pscustomobject]@{ Emoji = '🦒' ; Description = 'giraffe' }
        [pscustomobject]@{ Emoji = '🍎' ; Description = 'apple' }
        [pscustomobject]@{ Emoji = '🐧' ; Description = 'penguin' }
        [pscustomobject]@{ Emoji = '😊' ; Description = 'smiling face with smiling eyes' }
    )
}


Describe 'Template expansion' {
    Context 'Array of hashtables' {
        It 'Using PropertyName:   Returns <Emoji> (<Description>)' -ForEach $arrayOfHashtables {}
        It 'Using _.PropertyName: Returns <_.Emoji> (<_.Description>)' -ForEach $arrayOfHashtables {}
    }

    Context 'Array of objects' {
        It 'Using PropertyName:   Returns <Emoji> (<Description>)' -ForEach $arrayOfObjects {}
        It 'Using _.PropertyName: Returns <_.Emoji> (<_.Description>)' -ForEach $arrayOfObjects {}
    }
}

... are expanded and rendered like this by the "Pester Tests" extension:

... whereas they are expanded and rendered like this by Pester:

PowerShell version (tested with PS5 as well)

$PSVersionTable

Name                           Value
----                           -----
PSVersion                      7.4.1
PSEdition                      Core
GitCommitId                    7.4.1
OS                             Microsoft Windows 10.0.22631
Platform                       Win32NT
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0…}
PSRemotingProtocolVersion      2.3
SerializationVersion           1.1.0.1
WSManStackVersion              3.0

Pester Tests Extension version

Published
2023-07-31, 06:15:27
Last released
2023-08-01, 17:24:12
Last updated
2023-10-19, 19:25:47
Identifier
pspester.pester-test

Pester version

Get-Module -Name Pester

ModuleType Version    PreRelease Name                                ExportedCommands
---------- -------    ---------- ----                                ----------------
Script     5.5.0                 Pester                              ...

[Justin Grote]

It uses the same name processing as Pester, but using hooks it occurs prior to final output for performance, so there may be an issue here especially with that referencing of a property rather than a direct object.

Thanks for the note! I'll see if I can sort this but in the meantime look in the tests directly for tested/supported name cases.
https://github.com/pester/vscode-adapter/blob/main/sample/Tests/Basic.Tests.ps1

[Kevin Crouch]

I also had some good success with just creating a HashTable manually, so that it could parse directly from a template in the meantime
Previously, I was trying to use } -ForEach $AllAccountsT2 and Context "<_.GivenName> <_.SurName>-<_.SamAccountName>" {, but it was not populating any of the templates since they relied on Properties off the template.

To work around that I just created a HashTable from each returned case, then fed that Array of HashTables to the next block, and everything worked well for me and the templates filled in.

Describe "Tier 2 Accounts" {
    BeforeDiscovery -Scriptblock {
        $AllAccountsT2 = Get-ADUser -SearchBase 'OU=Tier 2,DC=CompanyDom,DC=org' -Filter * -Properties *
        $AllAccountsT2HashT = $AllAccountsT2 | Foreach {
            @{
                GivenName       = $_.GivenName
                SurName         = $_.SurName
                SamAccountName  = $_.SamAccountName
                CurrAdUserObj   = $_
            }
        }
    }
    Context "<GivenName> <SurName> - <SamAccountName> " {
        IT "tests" {} 
    } -ForEach $AllAccountsT2HashT
}

I'm passing $CurrAdUserObj so that I can be lazy inside my tests and just call for other attributes like $CurrAdUserObj.MemberOf or $CurrAdUserObj.DisplayName without having them declared in the "full" hashtable passed in.

Before, with the properties, these were just $_.MemberOf and $_.DisplayName, but it isn't much trouble with the $CurrAdUserObj to use