public static IReturnsResult <TMock> ReturnsUsingFixture <TMock, TResult>(this IReturns <TMock, TResult> setup, ISpecimenBuilder fixture) where TMock : class { if (setup == null) { throw new ArgumentNullException("setup"); } if (fixture == null) { throw new ArgumentNullException("fixture"); } return(setup.ReturnsUsingContext(new SpecimenContext(fixture))); }