PowerShell Script Module PreCache Ignores DefaultCommandPrefix in Manifest - Results in Tab Completion Errors

Question

Refer to this thread for background...
https://social.technet.microsoft.com/Forums/windowsserver/en-US/6507710a-5648-4f52-8d46-3bf6c75ac7f3/module-function-name-resolution-issues-with-defaultcommandprefix?forum=winserverpowershell
The issue is when PowerShell auto loads the meta data into the CommandAnalysis cache it loads the functions defined in a script module (*.psm1) without consideration that a manifest file (*.psd1) may contain a DefaultCommandPrefix declaration. As a result
if a user attempts to enter a function using tab completion PowerShell will offer the name as defined in the script module which fails to execute (name not recognized). Importing the module will make the correct name with prefix available for tab completion.
My recommended approach would be to include the DefaultCommandPrefix in the meta data cache during the initial population as a session is instantiated. Also, when a module is loaded explicitly by a user who specifies a -Prefix value the old references containing
the DefaultCommandPrefix would need to be removed.
William Busby, PMP

Answer 1

Hi William,
yes, that's something you'll either have to do the hard way or live with admin confusion.
If you're using Sapien's PowerShell Studio as an Editor (hint: Usually a great idea), you can very easily rename a function, even in a multi-file module project, by rightcklicking on the function-name and selecting "rename".
Alternatively you can do a bulk rename with Powershell:
Get all functions in your module (Load it and check exportedcommands)
loop over each function-name
calculate new name
search your entire project for all references and replace them.
Let me see ...
function Rename-ModulePrefix
[CmdletBinding()]
Param (
[Parameter(Position = 0, Mandatory = $true)]
[string]
$ModuleName,
[Parameter(Position = 1, Mandatory = $true)]
[string]
$OldPrefix,
[Parameter(Position = 2, Mandatory = $true)]
[string]
$NewPrefix,
[Parameter(Position = 3)]
[string]
$Path
# Catch all typos
Import-Module $ModuleName -ErrorAction 'Stop'
# Get root path if not manually passed
if (-not $PSBoundParameters["Path"])
$Path = (Get-Module $ModuleName).Path
# Get module files
$Files = Get-ChildItem -Path $path -Recurse -Include "*.ps1", "*.psm1", "*.psd1"
# Iterate over each file
foreach ($file in $Files)
# Null variable in case you get an empty file somewhere and run this from Win 7
$data = $null
# Get Content of file
$data = Get-Content $file
# Replace strings
foreach ($c in (Get-Module $ModuleName).ExportedCommands)
$newName = $c.Name -replace $OldPrefix, $NewPrefix
$data = $data | ForEach-Object { $_ -replace $c.Name, $newName }
# Write back to file
$data | Set-Content $file
While I didn't proof it, in theory this should do it (Make a backup before running it :) ).
Cheers,
Fred
There's no place like 127.0.0.1