Tab complete changed in inconvenient way for PS7 Preview3

[rkeithhill]

Tab-complete is finding files from somewhere (not sure where).

Steps to reproduce

1. dotnet new console -o HelloWorld
2. dotnet run
3. bi<tab>
4. <tab>

Expected behavior

Complete to `.\bin\Debug`

Actual behavior

completes to `B:` or other odd files:

Environment data

Name                           Value
----                           -----
PSVersion                      7.0.0-preview.3
PSEdition                      Core
GitCommitId                    7.0.0-preview.3
OS                             Microsoft Windows 10.0.18362
Platform                       Win32NT
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0…}
PSRemotingProtocolVersion      2.3
SerializationVersion           1.1.0.1
WSManStackVersion              3.0

[vexx32]

It looks kinda like it's tab-completing from $env:PATH? I don't remember it doing that before... I don't think it's necessarily a negative, that's somewhat helpful. The B: entry is an odd one, wonder where that cropped up from?

In any case, even the ones that might be useful here should probably end up at the bottom of the tab complete list, below any PowerShell commands (I notice Pester's BeforeAll is somewhere in the middle of the list, below several of the extraneous entries, for example).

[rkeithhill]

Or in this case, below any local files and directories.

[iSazonov]

Does it work well in 7.0.0-preview.2? Is it only Unix regression?

[vexx32]

Both @rkeithhill and I are seeing this on Windows. Not sure about other platforms. 😕

[iSazonov]

Thanks! I can repo on Windows. On 6.2.2 too. So it is not regression in 7.0. (I can repo without PSReadline too).

[iSazonov]

Although possibly it is not bug - for .\b<tab> I get extected results. I guess b<Tab> falls in last resort code path and it is expected behavior.

[TravisEz13]

I think honestly I regressed the 6.2 behavior in making a security fix and then restored the old behavior when an issue was filed for a regression and said here #10482 (comment)

I can look up the changes.

[TravisEz13]

These are the changes:
#9202
#9623