`$PROFILE` variable has changed type and behavior

[sburbano]

Prerequisites

• I have written a descriptive issue title.
• I have searched all issues to ensure it has not already been reported.
• I have read the troubleshooting guide.
• I am sure this issue is with the extension itself and does not reproduce in a standalone PowerShell instance.
• I have verified that I am using the latest version of Visual Studio Code and the PowerShell extension.

Summary

Since updating to the latest preview, the $PROFILE variable in the Integrated Console has changed its type, from String to PSCustomObject.

Before:

PS>$PROFILE.GetType()

IsPublic IsSerial Name                                     BaseType
-------- -------- ----                                     --------     
True     True     String                                   System.Object

After:

PS>$PROFILE.GetType()

IsPublic IsSerial Name                                     BaseType     
-------- -------- ----                                     --------     
True     False    PSCustomObject                           System.Object

This change in type also changes the way the variable is coerced to other types, output to console etc possibly breaking any script that use this variable.

Before:

PS>$PROFILE

C:\Users\sburbano\Documents\PowerShell\Microsoft.VSCode_profile.ps1

After:

PS>$PROFILE

AllUsersAllHosts                          AllUsersCurrentHost                                        CurrentUserAllHosts                                CurrentUserCurrentHost
----------------                          -------------------                                        -------------------                                ----------------------
C:\Program Files\PowerShell\7\profile.ps1 C:\Program Files\PowerShell\7\Microsoft.VSCode_profile.ps1 C:\Users\sburbano\Documents\PowerShell\profile.ps1 C:\Users\sburbano\Documents\PowerShell\Microsoft.VSCode_profile.ps1

In my case, for example, custom theme loading in the profile has stopped working, because this function has stopped working.

PS>Get-ThemesLocation
Join-Path: C:\Users\sburbano\Documents\PowerShell\Modules\oh-my-posh\2.0.487\defaults.ps1:5:17
Line |
   5 |          return (Join-Path (Split-Path -Parent $PROFILE) $folderName)
     |                  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     | Cannot find drive. A drive with the name '@{AllUsersAllHosts=C' does not exist.

Might be related to #3650

PowerShell Version

PS>$PSVersionTable

Name                           Value
----                           -----
PSVersion                      7.1.5
PSEdition                      Core
GitCommitId                    7.1.5
OS                             Microsoft Windows 10.0.19042
Platform                       Win32NT
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0…}       
PSRemotingProtocolVersion      2.3
SerializationVersion           1.1.0.1
WSManStackVersion              3.0

Visual Studio Code Version

1.62.0-insider
ff1e16eebb93af79fd6d7af1356c4003a120c563
x64

Extension Version

ms-vscode.powershell@2021.10.2

Steps to Reproduce

Compare the output of

PS>$PROFILE

in the PS Integrated Console and any other Powershell Console (regular pwsh.exe, Windows Terminal, ...)

Visuals

No response

Logs

No response

[SeeminglyScience]

Needs to be a PSObject wrapped string with additional PSNotePropertys:

PSObject profile = PSObject.AsPSObject("C:\CurrentUserCurrentHostPathEtc");
profile.Properties.Add(new PSNoteProperty("AllUsersAllHosts", "pathhere"));
profile.Properties.Add(new PSNoteProperty("AllUsersCurrentHost", "pathhere"));
profile.Properties.Add(new PSNoteProperty("CurrentUserAllHosts", "pathhere"));
profile.Properties.Add(new PSNoteProperty("CurrentUserCurrentHost", "pathhere"));

[sburbano]

This is inconsistent with pswh.exe .

Try this in a regular PS console.

PS>$PROFILE.GetType()

IsPublic IsSerial Name                                     BaseType
-------- -------- ----                                     --------
True     True     String                                   System.Object

PS>$PROFILE | Get-Member

   TypeName: System.String

Name                   MemberType            Definition
----                   ----------            ----------
[...]
AllUsersAllHosts       NoteProperty          string AllUsersAllHosts=C:\Program Files\PowerShell\7\profile.ps1
AllUsersCurrentHost    NoteProperty          string AllUsersCurrentHost=C:\Program Files\PowerShell\7\Microsoft.PowerShell_profile.ps1
CurrentUserAllHosts    NoteProperty          string CurrentUserAllHosts=C:\Users\sburbano\Documents\PowerShell\profile.ps1
CurrentUserCurrentHost NoteProperty          string CurrentUserCurrentHost=C:\Users\sburbano\Documents\PowerShell\Microsoft.PowerShell_profile.ps1
[...]

May be pwsh.exe is doing something under the covers or treating $PROFILE differently, idk. In fact, I have tried to Add-Member a simple string variable to no avail.

PS>$test = "Some string"
PS>$test.GetType()

IsPublic IsSerial Name                                     BaseType
-------- -------- ----                                     --------
True     True     String                                   System.Object

PS>Add-Member -InputObject $test -NotePropertyName "SomeProperty" -NotePropertyValue "SomeValue"
PS>Get-Member -InputObject $test

   TypeName: System.String

Name                 MemberType            Definition
----                 ----------            ----------
[ ommitted for brevity, but NO SomeProperty]

[sburbano]

Just for the sake of completeness...

This is even mentioned in the official documentation

[SeeminglyScience]

@sburbano strings are unfortunately very complicated when it comes to ETS properties. When handled in C#, it's pretty simple since no PowerShell engine magic gets in the way. In PowerShell you gotta be a bit explicit. More specifically the first line needs to be:

$test = [psobject]"Some string"

So typically any reference type object has it's manually added ETS members preserved between PSObject wrapper instances. When the engine inevitably unwraps the wrapper and later rewraps it, it looks up the base object in a member resurrection table and sticks them on the new wrapper. That makes it look and feel like it was never wrapped in the first place since all of this is supposed to be mostly invisible.

Strings specifically are special cased to work a bit more like primitives/other structs (most likely because they are immutable and can be interned). So if you want to add ETS members to a string you must preserve the PSObject wrapper instance.

In general that's not super feasible to do which is why I typically tell folks to just not do it, but it works fine for a automatic variable (and it's what SMA's ConsoleHost does, and what we did previously).

[sburbano]

@SeeminglyScience Wow!! I see!

PS>$test = [psobject]"Some string"
PS>$test.GetType()

IsPublic IsSerial Name                                     BaseType
-------- -------- ----                                     --------
True     True     String                                   System.Object

PS>Add-Member -InputObject $test -NotePropertyName "SomeProperty" -NotePropertyValue "Some value"
PS>Get-Member -InputObject $test

   TypeName: System.String

Name                 MemberType            Definition
----                 ----------            ----------
[...]
SomeProperty         NoteProperty          string SomeProperty=Some value

PS is like a box of chocolates... 😄

[SeeminglyScience]

Yeah PSObject is kind of hard to inspect since a pretty significant amount of objects are going to be invisibly wrapped in PSObject many times throughout their lifetime. Really when you call .GetType(), that's routed through the PSInvokeMemberBinder which controls method invocations are dynamically bound. For the most part, GetType() will never lie. Except with PSObjects when they're wrapping other objects.

One thing that never lies (currently) though is -is. $test -is [psobject] will return true if the object is currently wrapped in a PSObject.

It gets very confusing but thankfully it doesn't come up as a problem unless you look real close 😁