$([MSBuild]::MakeRelative()) returns different values on 16.10 than older version

[yodovicz]

Issue Description

Newest version of VisualStudio (MSBuild 16.10) return different values on msbuild property function MakeRelative() with paths ending backslash.

Steps to Reproduce

code: $([MSBuild]::MakeRelative('c:\windows\', 'c:\windows\system32\'))
MSBuild 16.10 returns: 'system32'
MSBuild 16.9 and older returns: 'system32\'

Expected Behavior

according to https://docs.microsoft.com/en-us/dotnet/api/system.uri.makerelativeuri?view=net-5.0
it should returns 'system32\'

Actual Behavior

returns 'system32'

Analysis

MSBuild unittests does not contains paths ending backslash
https://github.com/dotnet/msbuild/blob/main/src/Shared/UnitTests/FileUtilities_Tests.cs#L86

Versions & Configurations

16.10.0.26302

[pmisik]

Here is sample project to easily verify behavior has changed

<Project xmlns="http://schemas.microsoft.com/developer/msbuild/2003" DefaultTargets="Build">
  <Target Name="Build">
    <PropertyGroup>
	<_RelativeDir>$([MSBuild]::MakeRelative('c:\windows\', 'c:\windows\system32\'))</_RelativeDir>
    </PropertyGroup>
    <Message Text="MakeRelative('c:\windows\', 'c:\windows\system32\')): $(_RelativeDir)" />
    <Error Condition="!$(_RelativeDir.EndsWith('\'))" Text="_RelativeDir='$(_RelativeDir)' does not ends with backslash" />
  </Target>
</Project>

[BrunoJuchli]

This change causes execution of our application to fail. We're using System.Data.SQLite.Core which now fails to include the SQLite.Interop.dll as content.
When executing the application we get the following exception:

System.DllNotFoundException : Unable to load DLL 'SQLite.Interop.dll': The specified module could not be found. (Exception from HRESULT: 0x8007007E)
at System.Data.SQLite.UnsafeNativeMethods.sqlite3_config_none(SQLiteConfigOpsEnum op)
at System.Data.SQLite.SQLite3.StaticIsInitialized()
at System.Data.SQLite.SQLiteLog.Initialize(String className)
at System.Data.SQLite.SQLiteConnection..ctor(String connectionString, Boolean parseViaFramework)
at System.Data.SQLite.SQLiteConnection..ctor()

Also see https://sqlite.org/forum/forumpost/b691c7086468c80dafba99497df225b51994df5aaa934962415ba50e31a9796f

[dsparkplug]

The following line appears to be the cause of this issue:
https://github.com/dotnet/msbuild/pull/6311/files#diff-b62db5f7e7f90841af8ef58195eb4318cabc0742747ba3f2e97f10cfa21d6658R1081

[pmisik]

Related report
https://developercommunity.visualstudio.com/t/MSBuild::MakeRelative-in-VS-2019-Versi/1435347

[marcinzi]

We're hitting downstream build issues on SQLite.interop.dll as reported by Bruno
with no reasonable workaround other than downgrading build agent pool to self-hosted

[nzbart]

I know +1 comments are frowned upon, but at the same time they seem to be the only way to get things prioritised. We're experiencing the same problem with Sqlite. Therefore:

+1

[teh13th]

+1 to this problem.

[jeremy-morren]

We are also having the problem with System.Data.SQLite. This is a blocking issue, since no builds work.

[cmichaelingram]

Bit us too. Blocking as no builds work that use the SQLite nuget packages.