(OutputPath) Property Break / Regression in Recent 5.0 Sdk Patch

[Cooksauce]

Issue Description

A recent 5.0 Sdk patch changes the $(OutputPath) property on Windows & Linux. MacOS appears unaffected.

The break is that $(OutputPath) used to contain the trailing path separator (ie path/to/build/).
Now it does not include the trailing separator path/to/build.

This breaks custom build targets.

• This can be worked around... but the inconsistency between OS's may warrant a look.

Steps to Reproduce

MacOS:

• Create new dotnet project from any template (with Docker enabled)
• Add build target:

  <Target Name="PrintOutputPath" BeforeTargets="BeforeBuild">
    <Message Importance="high" Text="Output Path: '$(OutputPath)'" />
  </Target>

• Build In MacOS terminal
  Output (trimmed): Output Path: 'bin/Release/net5.0/'
• Build In Docker container (image: mcr.microsoft.com/dotnet/sdk:5.0)
  Output (trimmed): Output Path: '/app/build'

-- This reproduces in latest image mcr.microsoft.com/dotnet/sdk:5.0.403
-- Windows also appears to have this 'no trailing separator' behavior

Expected Behavior

$(OutputPath) should include the trailing slash to avoid breaking custom build targets/tools

Actual Behavior

$(OutputPath) does not include trailing slash on Windows & Linux

Ask us questions

Given the inconsistency between OS's I'm guessing this was not intentional?

[Forgind]

I think this is a dupe of #5965, but this has a nicer repro, and that one has more useful details around where the bug originated. My sense is that there's some important difference between <MyProperty Condition="!HasTrailingSlash('$(MyProperty)')">$(MyProperty)\</MyProperty> and <MyProperty>$([MSBuild]::EnsureTrailingSlash('$(MyProperty)'))</MyProperty>, but I can't figure out what it is by code inspection.

[Forgind]

Any chance you can provide a binlog of the version where it doesn't print a slash? What version are you using? I tried your repro on Windows, using current main to build it, and it printed it out with a slash.

[marcpopMSFT]

Close as needs more info. Please provide an https://aka.ms/binlog and reactivate if you still see this.