PSFunctionTools

1.0.0

functions/public/Get-FunctionAlias.ps1

Function Get-FunctionAlias {
    [cmdletbinding()]
    [alias("gfal", "ga")]
    [outputType("string")]
    Param(
        [Parameter(
            Position = 0,
            Mandatory,
            ValueFromPipelineByPropertyName,
            HelpMessage = "Specify the .ps1 or .psm1 file with defined functions."
        )]
        [alias("pspath")]
        [ValidateScript({
            If (Test-Path $_ ) {
                $True
                If ($_ -match "\.ps(m)?1$") {
                    $True
                }
                Else {
                    Throw "The path must be to a .ps1 or .psm1 file."
                    $False
                }
            }
            Else {
                Throw "Can't validate that $_ exists. Please verify and try again."
                $False
            }
        })]
        [string]$Path
    )
    Begin {
        Write-Verbose "[$((Get-Date).TimeofDay) BEGIN] Starting $($myinvocation.mycommand)"
    } #begin
    Process {
        $Path = Convert-Path -Path $path
        Write-Verbose "[$((Get-Date).TimeofDay) PROCESS]Processing $path for AST data."
        $AST = _getAST $path

        #parse out functions using the AST
        Write-Verbose "[$((Get-Date).TimeofDay) PROCESS]Parsing AST data for functions."
        $functions = $ast.FindAll( { $args[0] -is [System.Management.Automation.Language.FunctionDefinitionAst] }, $true)
        if ($functions.count -gt 0) {
            foreach ($f in $functions) {
                #thanks to https://twitter.com/PrzemyslawKlys for this suggestion
                $aliasAST = $f.FindAll( {
                        $args[0] -is [System.Management.Automation.Language.AttributeAst] -and
                        $args[0].TypeName.Name -eq 'Alias' -and
                        $args[0].Parent -is [System.Management.Automation.Language.ParamBlockAst]
                    }, $true)

                if ($aliasAST.positionalArguments) {
                    [pscustomobject]@{
                        PSTypeName = "PSFunctionAlias"
                        Name       = $f.name
                        Alias      = $aliasAST.PositionalArguments.Value
                    }
                }
            }
        } #if functions.count > 0
    } #process
    End {
        Write-Verbose "[$((Get-Date).TimeofDay) END ] Ending $($myinvocation.mycommand)"
    } #end
} #end function