targets (version 0.4.1)

tar_renv: Set up package dependencies for compatibility with renv

Description

Write package dependencies to a script file (by default, named _targets_packages.R in the root project directory). Each package is written to a separate line as a standard library() call (e.g. library(package)) so renv can identify them automatically.

Usage

tar_renv(
  extras = c("bs4Dash", "clustermq", "future", "gt", "markdown", "pingr", "rstudioapi",
    "shiny", "shinybusy", "shinyWidgets", "visNetwork"),
  path = "_targets_packages.R",
  callr_function = callr::r,
  callr_arguments = targets::callr_args_default(callr_function)
)

Arguments

extras

Character vector of additional packages to declare as project dependencies.

path

Character of length 1, path to the script file to populate with library() calls.

callr_function

A function from callr to start a fresh clean R process to do the work. Set to NULL to run in the current session instead of an external process (but restart your R session just before you do in order to clear debris out of the global environment). callr_function needs to be NULL for interactive debugging, e.g. tar_option_set(debug = "your_target"). However, callr_function should not be NULL for serious reproducible work.

callr_arguments

A list of arguments to callr_function.

Value

Nothing, invisibly.

Details

This function gets called for its side-effect, which writes package dependencies to a script for compatibility with renv. The generated file should not be edited by hand and will be overwritten each time tar_renv() is called.

The behavior of renv is to create and manage a project-local R library and keep a record of project dependencies in a file called renv.lock. To identify dependencies, renv crawls through code to find packages explicitly mentioned using library(), require(), or ::. However, targets manages packages in a way that hides dependencies from renv. tar_renv() finds package dependencies that would be otherwise hidden to renv because they are declared using the targets API. Thus, calling tar_renv this is only necessary if using tar_option_set() or tar_target() to use specialized storage formats or manage packages.

With the script written by tar_renv(), renv is able to crawl the file to identify package dependencies (with renv::dependencies()). tar_renv() only serves to make your targets project compatible with renv, it is still the users responsibility to call renv::init() and renv::snapshot() directly to initialize and manage a project-local R library. This allows your targets pipeline to have its own self-contained R library separate from your standard R library. See https://rstudio.github.io/renv/index.html for more information.

See Also

https://rstudio.github.io/renv/articles/renv.html

Other scripts: tar_edit(), tar_github_actions(), tar_helper_raw(), tar_helper(), tar_script()

Examples

# NOT RUN {
tar_dir({ # tar_dir() runs code from a temporary directory.
  tar_script({
    tar_option_set(packages = c("tibble", "qs"))
    list()
  }, ask = FALSE)
  tar_renv()
  writeLines(readLines("_targets_packages.R"))
})
tar_option_reset()
# }