Hello,
I don’t know if that’s what you’re looking for but I was able to have code coverage of an Angular application hosted in an ASP.NET Core web application (TypeScript / C# on same codebase).
Code: https://github.com/devpro/aspnetcore-angular-sample
SonarCloud: https://sonarcloud.io/dashboard?id=devpro.demo.angular-aspnetcore
It was not easy as first this is why I blogged about it (https://blog-bertrand-thomas.devpro.fr/2019/02/03/create-angular-asp-net-core-application-push-azure/).
Please let me know if you would like to try this approach.
Bertrand