Pester 5.50 Test scoping each block

Question

param (
    [Parameter()]
    $ParameterPath = "Approved-rule.json"
)

# BeforeDiscovery {
#     ## Store the data from the json file to be re-used
#     $parameterFile = Get-Content $ParameterPath  
# }

Describe "Rules validation (Base)" -Tag "CI" {
    BeforeAll {
        $parameterFile = Get-Content $ParameterPath 
        $incommingParamObject = $parameterFile.Parameters
        $rules = $parameterFile.Parameters.Test.value
    }
    Context "Validate for Parameter" {

        It "File should not be null or empty" {
            Write-Host "rule: $($rules)"
            $rules | Should -Not -BeNullOrEmpty
        }
    }

}

When i am running the pester script the rule is coming as empty value. How does the scoping in pester works does the BeforeAll block be a global or i should add BeforeDiscovery?

Another question where should I add a Inline function ?

When running the above pester code all the variables are getting printed null. The file exists with correct path.

Solution:

To resolve this issue, you should define your functions in the appropriate block based on where you need to use them. If you need to use a function/varaible in an It block, you should define it in a BeforeAll block. If you need to use a function in a Describe or Context block, you should define it in a BeforeDiscovery block.

Answer 1

You have a typo in your It statement, should be $rules instead of $rule and you're missing ConvertFrom-Json in your BeforeAll block, then your code should work fine.

Using this Json as an example:

• Approved-rule.json

{
  "Parameters": {
    "Test": {
      "value" : [
        "foo",
        "bar",
        "baz"
      ]
    }
  }
}

And the Pester test code:

param (
    [Parameter()]
    $ParameterPath = 'Approved-rule.json'
)

Describe 'Rules validation (Base)' -Tag 'CI' {
    BeforeAll {
        $parameterFile = Get-Content $ParameterPath | ConvertFrom-Json
        $incommingParamObject = $parameterFile.Parameters
        $rules = $parameterFile.Parameters.Test.value
    }
    Context 'Validate for Parameter' {
        It 'File should not be null or empty' {
            Write-Host "rule: $($rules)"
            $rules | Should -Not -BeNullOrEmpty
        }
    }
}

When running you can get:

Starting discovery in 1 files.
Discovery found 1 tests in 75ms.
Running tests.
rule: foo bar baz
[+] C:\Users\User\Documents\pwsh\Pester.test.ps1 240ms (65ms|103ms)
Tests completed in 250ms
Tests Passed: 1, Failed: 0, Skipped: 0 NotRun: 0