package_hooks_linter {lintr}

Package hooks linter

Description

Check various common "gotchas" in .onLoad(), .onAttach(), .Last.lib(), and .onDetach() namespace hooks that will cause ⁠R CMD check⁠ issues. See Writing R Extensions for details.

Usage

package_hooks_linter()

Details

1. .onLoad() shouldn't call cat(), message(), print(), writeLines(), packageStartupMessage(), require(), library(), or installed.packages().

2. .onAttach() shouldn't call cat(), message(), print(), writeLines(), library.dynam(), require(), library(), or installed.packages().

3. .Last.lib() and .onDetach() shouldn't call library.dynam.unload().

4. .onLoad() and .onAttach() should take two arguments, with names matching ⁠^lib⁠ and ⁠^pkg⁠; .Last.lib() and .onDetach() should take one argument with name matching ⁠^lib⁠.

Tags

correctness, package_development, style

See Also

linters for a complete list of linters available in lintr.

Examples

# will produce lints
lint(
  text = ".onLoad <- function(lib, ...) { }",
  linters = package_hooks_linter()
)

lint(
  text = ".onAttach <- function(lib, pkg) { require(foo) }",
  linters = package_hooks_linter()
)

lint(
  text = ".onDetach <- function(pkg) { }",
  linters = package_hooks_linter()
)

# okay
lint(
  text = ".onLoad <- function(lib, pkg) { }",
  linters = package_hooks_linter()
)

lint(
  text = '.onAttach <- function(lib, pkg) { loadNamespace("foo") }',
  linters = package_hooks_linter()
)

lint(
  text = ".onDetach <- function(lib) { }",
  linters = package_hooks_linter()
)