requireNamespace(pkg)/loadNamespace(pkg) of a package that is not declared
pkg::f or pkg:::f of a package that is not declared
library(pkg) of a package the Depends field already attaches
library(pkg)/require(pkg) in package code at all
pkg:::f of the package itself
a package in Imports nothing imports from
a package in Depends the NAMESPACE imports nothing from
S4 code without methods in Depends or Imports
a package the tests, vignettes, or examples load or access but the DESCRIPTION does not declare
a package a vignette's \\VignetteDepends{} or \\VignetteEngine{} needs but the DESCRIPTION does not declare
a VignetteBuilder package not declared in Depends, Imports, or Suggests
a VignetteBuilder field without a vignettes folder
an RdMacros package not in Depends or Imports
a header-only package (like BH) in Depends or Imports that belongs into LinkingTo
a declared package the signature database does not know
a declared package whose version requirements no version satisfies
library(pkg)/require(pkg)of a package declared in neither Depends nor Suggests nor Enhances