Add SourceLink to NuGet packages

[MiYanni]

Fixes: #5619

Adds the SourceLink functionality to our NuGet packages. It also makes our build marked with the deterministic flag.

Verification

I used the NuGet Package Explorer to verify the packages. When they started, they looked like this:

I enabled SourceLink but it was still showing issues. Seems I needed the EmbedUntrackedSources setting.

After adding EmbedUntrackedSources, the build was broken. After some investigation, I found an issue that was reported for the problem, but no workaround: dotnet/sourcelink#492
I looked into how the generated .g.cs files wanted to reference the .xaml. Then, I determined how to output them to that path. I added those targets to the affected projects. After that, we had SourceLink working.

I noticed the Deterministic flag was still red. Found that I needed to add ContinuousIntegrationBuild for it to add the /deterministic compiler flag. After that, everything was green.

Microsoft Reviewers: Open in CodeFlow

[drewnoakes]

This looks similar to what I've had to do to get this working in my own libraries (minus the XAML file bit). Thanks for the clear PR description too.

In one of my libs I also added these. Do you think they'd be useful here?

<Deterministic>true</Deterministic>
<IncludeSource>true</IncludeSource>

Also, do we specify PackageProjectUrl, PackageLicenseExpression, RepositoryType and RepositoryUrl anywhere?

[KirillOsenkov]

I think Deterministic property is already true by default in SDK-style projects.

[MiYanni]

This looks similar to what I've had to do to get this working in my own libraries (minus the XAML file bit). Thanks for the clear PR description too.

In one of my libs I also added these. Do you think they'd be useful here?

<Deterministic>true</Deterministic>
<IncludeSource>true</IncludeSource>

Also, do we specify PackageProjectUrl, PackageLicenseExpression, RepositoryType and RepositoryUrl anywhere?

I'll look into what Deterministic and IncludeSource actually do. My assumption is ContinuousIntegrationBuild sets Deterministic to true.

Package properties are here:

project-system/Directory.Build.props

Lines 102 to 104 in 7707226

	<PackageLicenseUrl>http://go.microsoft.com/fwlink/?LinkId=529443</PackageLicenseUrl>
	<RepositoryUrl>https://github.com/dotnet/project-system</RepositoryUrl>
	<PackageProjectUrl>$(RepositoryUrl)</PackageProjectUrl>

We use PackageLicenseUrl instead of PackageLicenseExpression, and we don't seem to have RepositoryType set. I can add that.

[MiYanni]

I think Deterministic property is already true by default in SDK-style projects.

According to what NuGet Package Explorer was showing, the assemblies were not deterministic until I set ContinuousIntegrationBuild to true. See the description for this PR.

[KirillOsenkov]

Yes, NuGet Package Explorer's definition of deterministic includes the deterministic compilation as well as normalized paths to source files in the Pdb. The Deterministic property only controls the compiler determinism, whereas ContinuousIntegrationBuild also turns on normalized Pdb paths (which may break local debugging scenarios as I've outlined above). I think ideally set ContinuousIntegrationBuild to true on CI only.

[MiYanni]

@drewnoakes I'm adding the Deterministic property but not the IncludeSource property. It seems to not function with the SymbolPackageFormat I'm adding. See: NuGet/Home#8589