fix(shim): Add 'Get-CommandPath()' to find git

[rashil2000]

Description

Without scoop-which, the shimming function was picking up the ~\scoop\shims directory as source. This corrects it.

Motivation and Context

Closes ScoopInstaller/Main#3562

How Has This Been Tested?

Checklist:

• I have read the Contributing Guide.
• I have updated the documentation accordingly.
• I have updated the tests accordingly.

[chawyehsu]

This is a bad implementation. To keep the libcore to be decoupled, it should never call other modules. An abstraction of extracting which from scoop-which to a reusable function would be better. Put it into libcore so functions elsewhere may use it when they need.

[rashil2000]

Why do we need to keep core.ps1 decoupled? IIRC we stopped importing it in the installation script.

Nevertheless this PR is mainly intended as a hotfix (which should go out with v2.0.0) otherwise bash shims will not work.

I'll try to implement a proper way later in a subsequent PR.

[niheaven]

I prefer a two-step check for this function: one for scoop-installed git, then a gcm one. scoop installed git could be checked by appdir and if not found, fall back to gcm.

[rashil2000]

Checking for scoop installed git using appdir is not feasible, plenty of packages provide the git.exe executable - git, git-with-openssh, git-without-openssh, deepgit, mingit, mingit-busybox etc. We can't put conditions for all of them.

[niheaven]

Hmm, so let's extract the main function of scoop-which and add it to core.ps1 and try to avoid using scoop-which in such a situation IMO. That's the best way.

[niheaven]

@rashil2000 Tweak some codes by using 'Get-ShimPathfromscoop-shim.ps1`, please test it, thanks.

[Cologler]

If a bin includes both *.ps1 and *.exe shims (like aria2c):

> gcm aria2c -all
...\shims\aria2c.ps1
...\shims\aria2c.exe

The command scoop which aria2c show 'aria2c' not found / not a scoop shim..

[niheaven]

The new shim system should use only .exe shims, and .ps1 shims are only used for .cmd or bash script.

Try remove all shims except scoop.* and scoop reset *, and this should be fixed.