new-pester-test

Create New Pester Test

Scaffold a Pester 5 test file following the *.Tests.ps1 naming convention.

Required Information

Before generating, ask for:

1. What are we testing? — a PowerShell function, a deployed Azure resource, or a pipeline script?
2. Unit or integration? — unit mocks Az cmdlets; integration tests run against real Azure
3. Function/script name — used for Describe block naming and file naming
4. What should it validate? — list success cases, failure/edge cases

Unit Test Template

# tests/unit/{FunctionName}.Tests.ps1
#Requires -Modules @{ ModuleName = 'Pester'; ModuleVersion = '5.0' }

BeforeAll {
    # Import the function under test via dot-sourcing
    . $PSScriptRoot/../../modules/{ModuleName}/{FunctionName}.ps1

    # Stub out Az cmdlets — never hit real Azure in unit tests
    Mock New-AzResourceGroupDeployment {
        [PSCustomObject]@{
            DeploymentName    = 'mock-deployment'
            ProvisioningState = 'Succeeded'
            Outputs           = @{}
        }
    }
}

Describe '{FunctionName}' {
    Context 'Given valid input' {
        It 'calls the Az cmdlet once with correct parameters' {
            {FunctionName} -ParameterA 'value-a' -ParameterB 'value-b'

            Should -Invoke New-AzResourceGroupDeployment -Times 1 -ParameterFilter {
                $ResourceGroupName -eq 'expected-rg'
            }
        }

        It 'returns a succeeded result' {
            $result = {FunctionName} -ParameterA 'value-a' -ParameterB 'value-b'
            $result.ProvisioningState | Should -Be 'Succeeded'
        }
    }

    Context 'Given invalid input' {
        It 'throws when required parameter is missing' {
            { {FunctionName} -ParameterB 'value-b' } | Should -Throw
        }

        It 'throws when environment is invalid' {
            { {FunctionName} -ParameterA 'invalid' } | Should -Throw -ExpectedMessage '*must be one of*'
        }
    }
}

Integration Test Template