Intellisense doesn't work after piping from custom cmdlet (Powershell ISE)

Question

If I type the following line in the PowerShell ISE editor, I get Intellisense after the dot operator in $_ variable:

Get-ChildItem ATextFile.txt | foreach { $_.FullName }

In this case, $_ is an instance of System.IO.FileSystemInfo. The editor will properly list all accessible members from this object.

Now, if I write:

function GetFile {
  return [System.IO.FileInfo]::new(".\ATextFile.txt")
}

GetFile | foreach { $_.FullName }

The script runs fine, but Intellisense doesn't work after the dot operator in $_.

Am I missing a syntax to make IntelliSense work correctly? Maybe an annotation to "document" the returning value?

Answer 1

You are looking for the OutputType attribute above the Param section:

function GetFile {
    [OutputType([System.IO.FileInfo])]
    Param(

    )

  return [System.IO.FileInfo]::new(".\ATextFile.txt")
}

---

Please consider to rename your file to reflect approved verbs e. g. Get-File. Also note that the return statement is not necessary in PowerShell, so your function should look like this:

function Get-File 
{
    [OutputType([System.IO.FileInfo])]
    Param
    (
    )

    [System.IO.FileInfo]::new(".\ATextFile.txt")
}