Add analyzers/fixers for Environment.ProcessPath and CurrentManagedThreadId

[stephentoub]

Fixes dotnet/runtime#43257
Fixes dotnet/runtime#42948

cc: @carlossanlop, @mavasani, @jkotas

[codecov]

Codecov Report

Merging #4909 (d45a6f6) into release/6.0.1xx-preview3 (c054652) will decrease coverage by 0.00%.
The diff coverage is 98.09%.

@@                     Coverage Diff                      @@
##           release/6.0.1xx-preview3    #4909      +/-   ##
============================================================
- Coverage                     95.57%   95.56%   -0.01%     
============================================================
  Files                          1175     1175              
  Lines                        269054   269300     +246     
  Branches                      16302    16314      +12     
============================================================
+ Hits                         257144   257363     +219     
- Misses                         9784     9805      +21     
- Partials                       2126     2132       +6     

[Youssef1313]

I think this should target .NET 6 branch (6.0.1xx-preview3).

[jmarolf]

@stephentoub as @Youssef1313 says, master is currently being used to service nuget packages. This PR should target https://github.com/dotnet/roslyn-analyzers/tree/release/6.0.1xx-preview3

[stephentoub]

Feedback addressed and rebased on release/6.0.1xx-preview3

[Youssef1313]

Test failure is unrelated and was fixed in dotnet/roslyn#51244

[Youssef1313]

The codefix could cleanup the now-unused usings. This is not necessary but probably good to have as a follow-up. Should I open an issue tracking this?

[stephentoub]

Do we do that with other analyzers? Removing usings seems orthogonal and a style preference, not something we should be doing automatically just because we happened to remove the last use of something in that namespace. We could actually be creating more work and confusion for the developer.

[stephentoub]

@mavasani, any feedback before it's merged? Thanks.

[mavasani]

Looks great to me!