Steps to reproduce

$:<CTRL SPACE>

# OR

tabexpansion2 '$:' 2 # result set shows that it found nothing to match

Expected behavior

Expected was a full list of all the variables that could be used at least with the notation $:

Actual behavior

No results are returned, or list is offered.

Environment data

Name                           Value
----                           -----
PSVersion                      7.0.0-preview2.27045
PSEdition                      Core
GitCommitId                    7.0.0-preview2.27045
OS                             Microsoft Windows 10.0.18941
Platform                       Win32NT
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0…}
PSRemotingProtocolVersion      2.3
SerializationVersion           1.1.0.1
WSManStackVersion              3.0

Previous versions behave the same way.

I believe this should work, since $: is a valid start to specifying a variable. See 033ef6c for a commit that would fix this issue.

It might need to be determined if the : representing a blank drive/scope/provider field should be stripped from the returned completions, when they are not needed), and if the common scopes and providers should still be included in the list.