How to debug S4 class in RStudio

Question

Here is my S4 class, which is saved in separate file and currently open in RStudio:

setClass(
  Class = 'some_cls', 
  slots = c(some_slot = 'numeric'),
)


setGeneric("some_method", function(self)
  standardGeneric("some_method"))
setMethod("some_method", 
          signature(self = "some_cls"), 
          function(self) {
            self@some_slot <- 5
            self
          }
)

In another file I execute:

some_obj <- new('some_cls')
some_obj <- some_method(some_obj)

I tried to debug some_method as I would normally do in RStudio. I put dot next to line self@some_slot <- 5, in I RStudio I clicked Source in top right corner, but code execution did not stop at breakpoint. What am I doing wrong?

Answer 1

This looks like a bug in RStudio; you might want to report it to them. The underlying infrastructure in R has no problem handling a situation like yours.

For example, if the first file is called test.R, and you want the breakpoint on line 12, just run

setBreakpoint("test.R#12")

and execution will break when you get there.