Public/New-PSFunction.ps1

<#
.SYNOPSIS
    Creates a new function file.
.DESCRIPTION
    Creates a new function file and scaffolds base structure, to the target module.
.PARAMETER Name
    <String> The name of the function to create.
.PARAMETER Module
    <String> The name of a module, or the parent path of a module manifest.
.PARAMETER Scope
    <String> The scope of the function according to Redeploy scaffolding standards. Allowed values: Private and Public. Default: Public.
.PARAMETER PesterTest
    <switch> If used, a Pester Test file will be created in the module.
.NOTES
    Written by Karl Wallenius, Redeploy AB.
#>

function New-PSFunction {
    [CmdletBinding()]
    param(
        [Parameter(Mandatory = $True, Position = 0)]
        [string]
        $Name,
        [Parameter(Mandatory = $False, Position = 1)]
        [string]
        $Module,
        [Parameter(Mandatory = $False, Position = 2)]
        [ValidateSet('Public', 'Private')]
        [string]
        $Scope = "Public",
        [Parameter(Mandatory = $False)]
        [switch]
        $PesterTest = $False
    )

    process {

        . "$PSScriptRoot\..\templates\t_function.ps1"

        $modulePath = $null 

        if ($Module.Contains("\")) {
            if (!(Test-Path $Module)) {
                throw "A module with that path does not exist."
            }
            $modulePath = $Module.Trim("\") + "\" + (Split-Path $Module -Leaf)
        } else {

            if ($Module -eq ".") {
                $path = (Resolve-Path $Module).Path
            } else {
                $path = (Get-Location).Path
            }

            $moduleName = Split-Path $path -Leaf
            $modulePath = Join-Path $path $moduleName 
        }

        $fileName = $Name + ".ps1"
        $filePath = Join-Path $modulePath "$Scope\$fileName"

        Write-Verbose "Creating function template..."
        $FunctionFileContent -replace "<name>", "$Name" | Out-File $filePath -Encoding utf8
        Write-Verbose "Function template is done."

        if ($PesterTest) {
            New-PSPesterTest -Module (Split-Path $modulePath -Parent) -Name $Name -Scope $Scope
        }
    }


}