How to copy metadata attributes from PackageReference to corresponding ReferencePath?

[Denis535]

There are PackageReference items with some metadata attributes. And there are corresponding ReferencePath items.
I need to move those metadata attributes from source PackageReference items to corresponding ReferencePath items.

MSBuild do it for ProjectReference but doesn't for PackageReference.
I'm not sure is it bug or by design. So, I have described it here https://github.com/dotnet/msbuild/issues/5809#issue-724350443

[Denis535]

I did it in the following way:

<Target Name="CopyMetadataFromPackageReferenceToReferencePath" Outputs="%(PackageReference.Identity)">
    <PropertyGroup>
        <Local_MyMetadata>%(PackageReference.MyMetadata)</Local_MyMetadata>
        <Local_NugetPackageId>%(PackageReference.Identity)</Local_NugetPackageId>
    </PropertyGroup>
    <ItemGroup Condition=" $(Local_MyMetadata) != '' ">
        <ReferencePath 
            MyMetadata="$(Local_MyMetadata)" 
            Condition=" '%(ReferencePath.NugetPackageId)' == '$(Local_NugetPackageId)' " />
    </ItemGroup>
</Target>

It works. But it only worked when I've moved/allocated some values into properties. I wonder why?
Also I'm wondering if there is a better way to do this? Now If I will have many metadata then I will be forced to write ItemGroup for each metadata. So, is it possible to do it better?

[Denis535]

I think the better way is to make new reference items.

// get references with MyMetadata == true
<Target Name="MakeReferences_1" Returns="@(MyReferences )">
    <ItemGroup>
        <MyReferences Include="@(ReferencePath -> WithMetadataValue( 'MyMetadata', 'true' ))" />
    </ItemGroup>
</Target>

// get references which are pointing on PackageReference with MyMetadata == true
<Target Name="MakeReferences_2" Outputs="%(PackageReference.Identity)" Returns="@(MyReferences )">
    <PropertyGroup>
        <Local_MyMetadata>%(PackageReference.MyMetadata)</Local_MyMetadata>
        <Local_NuGetPackageId>%(PackageReference.Identity)</Local_NuGetPackageId>
    </PropertyGroup>
    <ItemGroup Condition="$(Local_MyMetadata) == 'true'">
        <MyReferences Include="@(ReferencePath -> WithMetadataValue( 'NuGetPackageId', $(Local_NuGetPackageId) ))" />
    </ItemGroup>
</Target>

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