Support solution filters (*.slnf)

[sharwell]

Addresses dotnet/roslyn#47531 (review)

I'm not sure how to test this.

[filipw]

you can add a new test-asset representing slnf and add a similar test to this

omnisharp-roslyn/tests/OmniSharp.MSBuild.Tests/WorkspaceInformationTests.cs

Lines 23 to 48 in 433dd17

	public async Task TestProjectAndSolution()
	{
	using (var testProject = await TestAssets.Instance.GetTestProjectAsync("ProjectAndSolution"))
	using (var host = CreateMSBuildTestHost(testProject.Directory))
	{
	var workspaceInfo = await host.RequestMSBuildWorkspaceInfoAsync();
	Assert.Equal("ProjectAndSolution.sln", Path.GetFileName(workspaceInfo.SolutionPath));
	Assert.NotNull(workspaceInfo.Projects);
	var project = Assert.Single(workspaceInfo.Projects);
	Assert.Equal("ProjectAndSolution", project.AssemblyName);
	Assert.Equal("bin/Debug/netcoreapp2.1/", project.OutputPath.EnsureForwardSlashes());
	Assert.Equal("obj/Debug/netcoreapp2.1/", project.IntermediateOutputPath.EnsureForwardSlashes());
	var expectedTargetPath = $"{testProject.Directory}/{project.OutputPath}ProjectAndSolution.dll".EnsureForwardSlashes();
	Assert.Equal(expectedTargetPath, project.TargetPath.EnsureForwardSlashes());
	Assert.Equal("Debug", project.Configuration);
	Assert.Equal("AnyCPU", project.Platform);
	Assert.True(project.IsExe);
	Assert.False(project.IsUnityProject);
	Assert.Equal(".NETCoreApp,Version=v2.1", project.TargetFramework);
	var targetFramework = Assert.Single(project.TargetFrameworks);
	Assert.Equal("netcoreapp2.1", targetFramework.ShortName);
	}
	}

to ensure OmniSharp loads it correctly

[333fred]

Hmm @sharwell that new test failure is the same one that I observed locally, that went away on re-run :/

[filipw]

superseded by #2121

[sharwell]

@filipw works for me thanks!