tests/Help.Tests.ps1

$script:ModuleName = 'Chocolatey-tools'

# Removes all versions of the module from the session before importing
Get-Module $ModuleName | Remove-Module

$ModuleBase = Split-Path -Parent $MyInvocation.MyCommand.Path

# Get the list of functions we are not going to run tests against
$FunctionHelpTestExceptions = Get-Content -Path "$ModuleBase\Help.Exceptions.txt"

# For tests in .\Tests subdirectory
if ((Split-Path $ModuleBase -Leaf) -eq 'Tests') {
    $ModuleBase = Split-Path $ModuleBase -Parent
}

$Module = Import-Module $ModuleBase\$ModuleName.psd1 -PassThru -ErrorAction Stop
$commands = Get-Command -Module $module -CommandType Cmdlet, Function, Workflow  # Not alias

## When testing help, remember that help is cached at the beginning of each session.
## To test, restart session.

foreach ($command in $commands) {
    $commandName = $command.Name

    # Skip all functions that are on the exclusions list
    if ($script:FunctionHelpTestExceptions -contains $commandName) { continue } ## may not be correct check with a function that needs exceptions

    # The module-qualified command fails on Microsoft.PowerShell.Archive cmdlets
    $Help = Get-Help $commandName -ErrorAction SilentlyContinue

    Describe "Test help for $commandName" -Tag Help {

        # If help is not found, synopsis in auto-generated help is the syntax diagram
        It "should not be auto-generated" {
            $Help.Synopsis | Should Not BeLike '*`[`<CommonParameters`>`]*'
        }

        # Should be a description for every function
        It "gets description for $commandName" {
            $Help.Description | Should Not BeNullOrEmpty
        }

        # Should be at least one example
        It "gets example code from $commandName" {
            ($Help.Examples.Example | Select-Object -First 1).Code | Should Not BeNullOrEmpty
        }

        # Should be at least one example description
        It "gets example help from $commandName" {
            ($Help.Examples.Example.Remarks | Select-Object -First 1).Text | Should Not BeNullOrEmpty
        }

        Context "Test parameter help for $commandName" {

            $Common = 'Debug', 'ErrorAction', 'ErrorVariable', 'InformationAction', 'InformationVariable', 'OutBuffer', 'OutVariable',
            'PipelineVariable', 'Verbose', 'WarningAction', 'WarningVariable'

            $parameters = $command.ParameterSets.Parameters | Sort-Object -Property Name -Unique | Where-Object Name -notin $common
            $parameterNames = $parameters.Name
            $HelpParameterNames = $Help.Parameters.Parameter.Name | Sort-Object -Unique

            foreach ($parameter in $parameters) {
                $parameterName = $parameter.Name
                $parameterHelp = $Help.parameters.parameter | Where-Object Name -EQ $parameterName

                # Should be a description for every parameter
                It "gets help for parameter: $parameterName : in $commandName" {
                    $parameterHelp.Description.Text | Should Not BeNullOrEmpty
                }

                # Required value in Help should match IsMandatory property of parameter
                It "help for $parameterName parameter in $commandName has correct Mandatory value" {
                    $codeMandatory = $parameter.IsMandatory.toString()
                    $parameterHelp.Required | Should Be $codeMandatory
                }

                # Parameter type in Help should match code
                It "help for $commandName has correct parameter type for $parameterName" {
                    $codeType = $parameter.ParameterType.Name
                    # To avoid calling Trim method on a null object.
                    $helpType = if ($parameterHelp.parameterValue) { $parameterHelp.parameterValue.Trim() }
                    $helpType | Should be $codeType
                }
            }

            foreach ($helpParm in $HelpParameterNames) {
                # Shouldn't find extra parameters in help.
                It "finds help parameter in code: $helpParm" {
                    $helpParm -in $parameterNames | Should Be $true
                }
            }
        }
    }
}