[R-pkg-devel] Analysing namespace reverse dependencies

[Roger Bivand]

On Sat, 9 Mar 2019, Iñaki Ucar wrote:

> On Sat, 9 Mar 2019 at 15:07, Roger Bivand <Roger.Bivand using nhh.no> wrote:
>>
>> Hi,
>>
>> Is anyone aware of tools permitting the listing of functions in the
>> namespace of package A used by package B when package B declares that it
>> depends on A, suggests A, or imports(A) without specifying the functions
>> from A that B is using? If B imports functions from A, and uses
>> importsFrom() in its NAMESPACE, the information can be recovered by
>> inspecting its NAMESPACE file (assuming that the entries are correct), but
>> not otherwise.
>
> I don't know of any specific tool, but the following function may help:
>
> inspect_functions <- function(pkg, from) {
>  regex <- paste0("(", paste(from, collapse="|"), ")::[[:alnum:]._]*")
>  ns <- getNamespace(pkg)
>  x <- sapply(ls(ns, all.names=TRUE), function(x) {
>    f <- get(x, envir=ns)
>    if (!is.function(f))
>      return(NULL)
>    b <- unlist(strsplit(as.character(body(f)), "\n"))
>    unique(regmatches(b, regexpr(regex, b)))
>  })
>  x[sapply(x, Negate(length))] <- NULL
>  x
> }

Thanks! This gives function calls directly using inspect_functions("B", 
"A"), but as of now does not catch methods, which are reported by 
pkgapi::map_package(). Very useful to compare insights!

Roger

>
> Example:
>
> inspect_functions("units", c("pillar", "xml2"))
> #> $.read_ud_db
> #> [1] "xml2::read_xml"
> #>
> #> $.read_ud_db_symbols
> #> [1] "xml2::read_xml"     "xml2::xml_find_all" "xml2::xml_contents"
> #>
> #> $.ud_db_xml_list_as_dataframe
> #> [1] "xml2::xml_children" "xml2::xml_length"   "xml2::xml_find_all"
> #> [4] "xml2::xml_text"
> #>
> #> $format_type_sum.type_sum_units
> #> [1] "pillar::style_subtle"
> #>
> #> $pillar_shaft.mixed_units
> #> [1] "pillar::new_pillar_shaft_simple"
> #>
> #> $pillar_shaft.units
> #> [1] "pillar::new_pillar_shaft_simple"
> #>
> #> $valid_udunits_prefixes
> #> [1] "xml2::xml_children" "xml2::xml_find_all" "xml2::xml_text"
> #> [4] "xml2::xml_double"
>
> Iñaki
>

-- 
Roger Bivand
Department of Economics, Norwegian School of Economics,
Helleveien 30, N-5045 Bergen, Norway.
voice: +47 55 95 93 55; e-mail: Roger.Bivand using nhh.no
https://orcid.org/0000-0003-2392-6140
https://scholar.google.no/citations?user=AWeghB0AAAAJ&hl=en