This article presents a study on the quality and execution of research code from publicly-available replication datasets at the Harvard Dataverse repo.
"The infrequent usage and absence of libraries also tell us what researchers are not doing in their projects. In particular, libraries that are used for code testing, such as runit, testthat, tinytest and unitizer, were not present."
Yeah, I could have told you that *grumble*
A large-scale study on research code quality and execution - Scientific Data