Reinstate macro loading

[jayhesselberth]

This code was accidentally removed from rd_file() in #2759 :

macros <- tools::loadPkgRdMacros(pkg_path)
set_classes(tools::parse_Rd(path, macros = macros, encoding = "UTF-8"))

Should create a dummy macro for testing purposes?

 rd_file <- function(path, pkg_path = NULL) {
-  if (getRversion() >= "3.4.0") {
-    macros <- tools::loadPkgRdMacros(pkg_path)
-    set_classes(tools::parse_Rd(path, macros = macros, encoding = "UTF-8"))
-  } else if (getRversion() >= "3.2.0") {
-    macros <- tools::loadPkgRdMacros(pkg_path, TRUE)
-    set_classes(tools::parse_Rd(path, macros = macros, encoding = "UTF-8"))
-  } else {
-    set_classes(tools::parse_Rd(path, encoding = "UTF-8"))
-  }
+  set_classes(tools::parse_Rd(path, encoding = "UTF-8"))
 }

Originally posted by @bastistician in #2759 (comment)

[jayhesselberth]

@bastistician can you install dev pkgdown and confirm that macros work? Thanks.

[bastistician]

I had already tried a patched version locally where I simply restored just the original >= "3.4.0" branch and that worked as expected. You seem to have done the same so it should be ok.