Microsoft/VSProjectSystem

I'm trying to read the value of a project property that is defined inside a target, like so:

  <Target Name="Test">
    <PropertyGroup>
      <Foo>Kirk</Foo>
    </PropertyGroup>
  </Target>

Thus, the target must run before the Foo property has a value. In our MPFProj-based project system, this worked fine -- just run the target and read the property, as per normal. MPFProj uses the MSBuild API directly.

In an attempt to do the same in our new CPS-based project, we use IBuildProject.BuildAsync and GetEvaluatedPropertyValueAsync. However, the Foo property returns an empty string.

Here is the code:

                        var buildResult = await configuredProject.Services.Build.BuildAsync(new[] { "Test" }, cancellationToken: default, includeUnsavedChanges: true);
                        Debug.Assert(buildResult.OverallResult == BuildResultCode.Success);

                        var f1 = await configuredProject.Services.ProjectPropertiesProvider.GetCommonProperties().GetEvaluatedPropertyValueAsync("Foo");

                        using (var access = await projectLockService.ReadLockAsync())
                        {
                            var project = await access.GetProjectAsync(configuredProject);
                            var projectInstance = BuildManager.DefaultBuildManager.GetProjectInstanceForBuild(project);
                            var success = projectInstance.Build("Test", loggers: null);
                            Debug.Assert(success);

                            var f2 = projectInstance.GetPropertyValue("Foo");
                        }

In the above f1 is an empty string, while f2 correctly prints out the Foo property's value of "Kirk".

Any thoughts on why? It makes me nervous about using IBuildProject as opposed to MSBuild directly.

Thanks in advance.