Validate-MandatoryOptionalParameters.ps1

<#
.SYNOPSIS
Checks parameters of a specific command for parameters that should have a value but are not Mandatory.

.DESCRIPTION
If a parameter is not marked as Mandatory but the intention is for a value to be supplied, this function 
will look for an alias that begins with the string "Required_". If such an alias is found and the 
parameter is not bound, this function will throw an exception or set a breakpoint depending on the 
options supplied.

.PARAMETER Context
You must pass $MyInvocation.MyCommand as the value of this parameter.

.PARAMETER BoundParams
You must pass $PSBoundParameters as the value of this parameter. It can also be supplied by pipeline.

.PARAMETER SetBreakpoint
If this is set, then an exception will not be thrown. Instead, a breakpoint will be set on the line 
where this function was called. Because that is earlier in the stack however, the breakpoint will 
not be hit unless the parameter fails validation again.

.PARAMETER Debug
If you set -Debug with -SetBreakpoint, then the breakpoint info will be written to the Debug stream.

.NOTES
SetBreakpoint is not well-tested and may not work on scripts that aren't saved to disk.

.EXAMPLE
$PSBoundParameters | Validate-MandatoryOptionalParameters -Context $MyInvocation.MyCommand

.LINK
https://www.briantist.com/how-to/throw-exception-on-unbound-mandatory-powershell-parameter/

#>
function Validate-MandatoryOptionalParameters {
[CmdletBinding()]
param(
    [Parameter(
        Mandatory=$true
    )]
    [System.Management.Automation.CommandInfo]
    $Context ,

    [Parameter(
        Mandatory=$true,
        ValueFromPipeline=$true
    )]
    [System.Collections.Generic.Dictionary[System.String,System.Object]]
    $BoundParams ,

    [Switch]
    $SetBreakpoint
)

    Process {
        foreach($param in $Context.Parameters.GetEnumerator()) {
            if ($param.Value.Aliases.Where({$_ -imatch '^Required_'})) {
                if (!$BoundParams[$param.Key]) {
                    if ($SetBreakpoint) {
                        $stack = Get-PSCallStack | Select-Object -Index 1
                        Set-PSBreakpoint -Line $stack.ScriptLineNumber -Script $stack.ScriptName | Write-Debug
                    } else {
                        throw [System.ArgumentException]"'$($param.Key)' in command '$($Context.Name)' must be supplied by the caller."
                    }
                }
            }
        }
    }
}

Full explanation and examples are available here.