Powershell: Get-Command: Using global function scope not working and starts throwing in PowerShell7-preview1

[bergmeister]

Steps to reproduce

Running the PSScriptAnalyzer test suite with PowerShell 7-preview1 has exposed a feature that does not seem to be implemented in current and old versions of PowerShell but starting with PowerShell7-preview1, the cmdlet throws an error

function global:Get-SimpleFunction { }
Get-Command global:Get-SimpleFunc*

Expected behavior

In PowerShell 6.2.1 (and 5.1), Get-Command does not return anything (which I think is a bug or unfinished feature) but at least no error should be thrown. Ideally the cmdlet should also be returned.

Actual behavior

Starting with PowerShell7-preview1, the cmdlet throws an error, which definitely is a regression and will affect users of PSScriptAnalyzers (because PSSA issues Get-Command calls under the hood for some of its analysis of the loaded user's code)

Get-Command : Cannot find drive. A drive with the name 'global' does not exist.
At line:1 char:42
+ ... ion global:Get-SimpleFunction { }; Get-Command global:Get-SimpleFunc*
+                                        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo          : ObjectNotFound: (global:String) [Get-Command], DriveNotFoundException
+ FullyQualifiedErrorId : DriveNotFound,Microsoft.PowerShell.Commands.GetCommandCommand

The problem is not so much that no object is being returned but rather that now an error is thrown. We need to review if this is by design or not.

Environment data

Name                           Value
----                           -----
PSVersion                      7.0.0-preview.1
PSEdition                      Core
GitCommitId                    7.0.0-preview.1
OS                             Microsoft Windows 10.0.17763
Platform                       Win32NT
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0…}
PSRemotingProtocolVersion      2.3
SerializationVersion           1.1.0.1
WSManStackVersion              3.0

[rkeithhill]

Looks like this is a dupe of (or related to) #9396.

[bergmeister]

Here is the full stack trace btw (when built from source on latest master commit f222a686c5710ce31cbfd77c699e1c1d635a1091), it throws from here
https://github.com/PowerShell/PowerShell/blob/bd6fdae73520931f0d27a29d6290e18761772141/src/System.Management.Automation/engine/SessionStateDriveAPIs.cs#L485-L494
The private PSDriveInfo GetDrive(string name, bool automount) is being called with name="global" and automount=false.

[iSazonov]

@bergmeister Please test with https://github.com/PowerShell/PowerShell/pull/9793 - is it resolve the issue too?

[bergmeister]

@iSazonov Yes, PR #9793 indeed seems to fix it (I downloaded the zip of the build to test it)

[TravisEz13]

@bergmeister What do you mean by fix

With #9793 this is what I get

PS > function global:foo {}
PS > gcm global:foo
gcm : The term 'global:foo' is not recognized as the name of a cmdlet, function, script file, or operable program.
Check the spelling of the name, or if a path was included, verify that the path is correct and try again.
At line:1 char:1
+ gcm global:foo
+ ~~~~~~~~~~~~~~
+ CategoryInfo          : ObjectNotFound: (global:foo:String) [Get-Command], CommandNotFoundException
+ FullyQualifiedErrorId : CommandNotFoundException,Microsoft.PowerShell.Commands.GetCommandCommand

And the same error in 7.0.0-preview.1 before his fix.

[TravisEz13]

Perhaps https://github.com/PowerShell/PowerShell/pull/9623 fixed this?

[bergmeister]

@TravisEz13 By 'fixed', I meant that the example given in this issue does not throw any more:

function global:Get-SimpleFunction { }
Get-Command global:Get-SimpleFunc*

But you are right that your example still throws, removing the * at the end of my example (i.e. Get-Command global:Get-SimpleFunc makes it throw again

[TravisEz13]

@bergmeister I'm going to close this issue. I think the issue is fixed. Feel free to update the test I added.

[bergmeister]

@TravisEz13 I just pulled the latest changes from master (f5e3de036e84f37820eb1dac635c337f8fc17718) and your use case is not fixed (but the one that I raised in this issue)

PS C:\Users\cberg\git\PowerShell> function global:foo {}
PS C:\Users\cberg\git\PowerShell> gcm global:foo
gcm : The term 'global:foo' is not recognized as the name of a cmdlet, function, script file, or operable program.
Check the spelling of the name, or if a path was included, verify that the path is correct and try again.
At line:1 char:1
+ gcm global:foo
+ ~~~~~~~~~~~~~~
+ CategoryInfo          : ObjectNotFound: (global:foo:String) [Get-Command], CommandNotFoundException
+ FullyQualifiedErrorId : CommandNotFoundException,Microsoft.PowerShell.Commands.GetCommandCommand

PS C:\Users\cberg\git\PowerShell> $PSVersionTable

Name                           Value
----                           -----
PSVersion                      7.0.0-preview.1
PSEdition                      Core
GitCommitId                    7.0.0-preview.1-18-gf5e3de036e84f37820eb1dac635c337f8fc17718
OS                             Microsoft Windows 10.0.17763
Platform                       Win32NT
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0…}
PSRemotingProtocolVersion      2.3
SerializationVersion           1.1.0.1
WSManStackVersion              3.0

[iSazonov]

Reopen until we fix the second issue.

[TravisEz13]

I verified this is the same functionality as in 5.1

[TravisEz13]

Please open a feature request if you would like new functionality.