Add-AssertionOperator

SYNOPSIS

Register an Assertion Operator with Pester

SYNTAX

Add-AssertionOperator [-Name] <String> [-Test] <ScriptBlock> [[-Alias] <String[]>] [[-InternalName] <String>]
[-SupportsArrayInput] [<CommonParameters>]

DESCRIPTION

This function allows you to create custom Should assertions.

EXAMPLES

EXAMPLE 1

function BeAwesome($ActualValue, [switch] $Negate)
{
[bool] $succeeded = $ActualValue -eq 'Awesome'
if ($Negate) { $succeeded = -not $succeeded }
if (-not $succeeded)
{
if ($Negate)
{
$failureMessage = "{$ActualValue} is Awesome"
}
else
{
$failureMessage = "{$ActualValue} is not Awesome"
}
}
return New-Object psobject -Property @{
Succeeded = $succeeded
FailureMessage = $failureMessage
}
}
Add-AssertionOperator -Name BeAwesome `
-Test $function:BeAwesome `
-Alias 'BA'
PS C:\> "bad" | should -BeAwesome
{bad} is not Awesome

PARAMETERS

-Name

The name of the assertion. This will become a Named Parameter of Should.

Type: String
Parameter Sets: (All)
Aliases:
Required: True
Position: 1
Default value: None
Accept pipeline input: False
Accept wildcard characters: False

-Test

The test function. The function must return a PSObject with a [Bool]succeeded and a [string]failureMessage property.

Type: ScriptBlock
Parameter Sets: (All)
Aliases:
Required: True
Position: 2
Default value: None
Accept pipeline input: False
Accept wildcard characters: False

-Alias

A list of aliases for the Named Parameter.

Type: String[]
Parameter Sets: (All)
Aliases:
Required: False
Position: 3
Default value: @()
Accept pipeline input: False
Accept wildcard characters: False

-InternalName

If -Name is different from the actual function name, record the actual function name here. Used by Get-ShouldOperator to pull function help.

Type: String
Parameter Sets: (All)
Aliases:
Required: False
Position: 4
Default value: None
Accept pipeline input: False
Accept wildcard characters: False

-SupportsArrayInput

Does the test function support the passing an array of values to test.

Type: SwitchParameter
Parameter Sets: (All)
Aliases:
Required: False
Position: Named
Default value: False
Accept pipeline input: False
Accept wildcard characters: False

CommonParameters

This cmdlet supports the common parameters: -Debug, -ErrorAction, -ErrorVariable, -InformationAction, -InformationVariable, -OutVariable, -OutBuffer, -PipelineVariable, -Verbose, -WarningAction, and -WarningVariable. For more information, see about_CommonParameters.

INPUTS

OUTPUTS

NOTES

RELATED LINKS