QC: QC Checks for R Code and/or Documentation

Description Usage Arguments Details Value


Functions for performing various quality control (QC) checks on R code and documentation, notably on R packages.


checkDocFiles(package, dir, lib.loc = NULL)
checkDocStyle(package, dir, lib.loc = NULL)
checkReplaceFuns(package, dir, lib.loc = NULL)
checkS3methods(package, dir, lib.loc = NULL)




a character string naming an installed package.


a character string specifying the path to a package's root source directory. This should contain the subdirectories ‘R’ (for R code) and ‘man’ with R documentation sources (in Rd format). Only used if package is not given.


a character vector of directory names of R libraries, or NULL. The default value of NULL corresponds to all libraries currently known. The specified library trees are used to search for package.


checkDocFiles checks, for all Rd files in a package, whether all arguments shown in the usage sections of the Rd file are documented in its arguments section. It also reports duplicated entries in the arguments section, and ‘over-documented’ arguments which are given in the arguments section but not in the usage. Note that the match is for the usage section and not a possibly existing synopsis section, as the usage is what gets displayed.

checkDocStyle investigates how (S3) methods are shown in the usages of the Rd files in a package. It reports the methods shown by their full name rather than using the Rd \method markup for indicating S3 methods. Earlier versions of R also reported about methods shown along with their generic, which typically caused problems for the documentation of the primary argument in the generic and its methods. With \method now being expanded in a way that class information is preserved, joint documentation is no longer necessarily a problem. (The corresponding information is still contained in the object returned by checkDocStyle.)

checkReplaceFuns checks whether replacement functions or S3/S4 replacement methods in the package R code have their final argument named value.

checkS3methods checks whether all S3 methods defined in the package R code have all arguments of the corresponding generic, with positional arguments of the generics in the same positions for the method. As an exception, the first argument of a formula method may be called formula even if this is not the name used by the generic. The rules when ... is involved are subtle: see the source code. Functions recognized as S3 generics are those with a call to UseMethod in their body, internal S3 generics (see InternalMethods), and S3 group generics (see Math). Possible dispatch under a different name is not taken into account. The generics are sought first in the given package, then in the base package and (currently) the packages graphics, stats, and utils added in R 1.9.0 by splitting the former base, and, if an installed package is tested, also in the loaded namespaces/packages listed in the package's ‘DESCRIPTION’ Depends field.

nonS3methods(package) returns a character vector with the names of the functions in package which ‘look’ like S3 methods, but are not. Using package = NULL returns all known examples.

langElts is a character vector of names of “language elements” of R. These are implemented as “very primitive” functions (no argument list; print()ing as .Primitive("<name>")).

If using an installed package, the checks needing access to all R objects of the package will load the package (unless it is the base package), after possibly detaching an already loaded version of the package.


The functions return objects of class the same as the respective function names containing the information about problems detected. There are print methods for nicely displaying the information contained in such objects.

Questions? Problems? Suggestions? Tweet to @rdrrHQ or email at ian@mutexlabs.com.

Please suggest features or report bugs in the GitHub issue tracker.

All documentation is copyright its authors; we didn't write any of that.