FunctionReporter incorrectly parses decorated functions

[jayqi]

Logging an issue where FunctionReporter is having trouble parsing some functions, with the suspected cause being related to the use of decorators. Thank you to @Manusreekumar who reported this offline a few weeks ago.

The functions in question were using the decorator package. A minimal reproducible example is still needed, as well as more research into what common decorator frameworks or packages exist for R.