.net core MSBuild normalizes slashes when it shouldn't

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Repro steps:

1. On linux, get the latest CLI
2. Create a new project “test.csproj”(dotnet new)
3. Run dotnet msbuild /p:RestoreSources=/tmp/some-source%3Bhttps://api.nuget.org/v3/index.json /t:restore test.csproj /v:diag > output
4. In output file, search “RestoreSources” and “Sources”.

You can find RestoreSources = /tmp/some-source;https://api.nuget.org/v3/index.json Sources= /tmp/some-source;https:/api.nuget.org/v3/index.json

The target file: https://github.com/NuGet/NuGet.Client/blob/dev/src/NuGet.Core/NuGet.Build.Tasks/NuGet.targets#L415 <Sources>$(RestoreSources)<Sources>

The known workaround is to escape the slash so MSBuild treats it as a literal: dotnet msbuild /p:RestoreSources=/tmp/some-source%3Bhttps:%2F%2Fapi.nuget.org/v3/index.json /t:restore test.csproj /v:diag > output

[r3h0]

@stan-sz, more that don’t work: \, $([MSBuild]::Escape(\)). However, %5C does work for me. Here’s how I used it for a multi-line command:

  <Target Name="GenerateGrpcSources" BeforeTargets="CoreCompile">
    <Exec Command="/bin/bash -ce &quot;
    echo 'Generating code...';
    $(NuGetPackageRoot)google.protobuf.tools/3.5.1/tools/linux_x64/protoc %5C
        -I$(NuGetPackageRoot)google.protobuf.tools/3.5.1/tools/google/protobuf %5C
        --proto_path=$(NuGetPackageRoot)google.protobuf.tools/3.5.1/tools %5C
        --proto_path=$(ProjectDir)Protobuf %5C
        --csharp_out=$(ProjectDir)Messages %5C
        $(ProjectDir)Protobuf/*.proto %5C
        ;
    echo 'Done generating code.';
    &quot;" />
  </Target>

[Happypig375]

How is this open for 6 years with Priority:1 removed