Manipulate DESCRIPTION Files.
desc
Parse DESCRIPTION files
Parse, manipulate and reformat DESCRIPTION files. The package provides two APIs, one is object oriented, the other one is procedural and manipulates the files in place.
Installation
# Install the released version from CRAN
install.packages("desc")
# Or the development version from GitHub:
# install.packages("pak")
pak::pak("r-lib/desc")
The object oriented API
library(desc)
Introduction
The object oriented API uses R6 classes.
Loading or creating new DESCRIPTION files
A new description object can be created by reading a DESCRIPTION file form the disk. By default the DESCRIPTION file in the current directory is read:
desc <- description$new()
desc
#> Package: desc
#> Title: Manipulate DESCRIPTION Files
#> Version: 1.0.0
#> Author: Gábor Csárdi
#> Maintainer: Gábor Csárdi <[email protected]>
#> Description: Tools to read, write, create, and manipulate DESCRIPTION
#> files. It is intented for packages that create or manipulate other
#> packages.
#> License: MIT + file LICENSE
#> URL: https://github.com/r-lib/desc
#> BugReports: https://github.com/r-lib/desc/issues
#> Imports:
#> R6
#> Suggests:
#> newpackage,
#> testthat,
#> whoami
#> Encoding: UTF-8
#> LazyData: true
#> RoxygenNote: 5.0.0
A new object can also be created from scratch:
desc2 <- description$new("!new")
desc2
#> Package: {{ Package }}
#> Title: {{ Title }}
#> Version: 1.0.0
#> Authors@R (parsed):
#> * Jo Doe <[email protected]> [aut, cre]
#> Maintainer: {{ Maintainer }}
#> Description: {{ Description }}
#> License: {{ License }}
#> URL: {{ URL }}
#> BugReports: {{ BugReports }}
#> Encoding: UTF-8
Normalizing DESCRIPTION files
Most DESCRIPTION fields may be formatted in multiple equivalent ways. desc does not reformat fields, unless they are updated or reformatting is explicitly requested via a call to the normalize() method or using the normalize argument of the write() method.
Querying, changing and removing fields
get() and set() queries or updates a field:
desc$set("Package", "foo")
desc$get("Package")
#> Package
#> "foo"
They work with multiple fields as well:
desc$set(Package = "bar", Title = "Bar Package")
desc$get(c("Package", "Title"))
#> Package Title
#> "bar" "Bar Package"
Dependencies
Package dependencies can be set and updated via an easier API:
desc$get_deps()
#> type package version
#> 1 Suggests testthat *
#> 2 Suggests whoami *
#> 3 Suggests newpackage *
#> 4 Imports R6 *
desc$set_dep("mvtnorm")
desc$set_dep("Rcpp", "LinkingTo")
desc$get_deps()
#> type package version
#> 1 Suggests testthat *
#> 2 Suggests whoami *
#> 3 Suggests newpackage *
#> 4 Imports mvtnorm *
#> 5 Imports R6 *
#> 6 LinkingTo Rcpp *
desc
#> Package: bar
#> Title: Bar Package
#> Version: 1.0.0
#> Author: Gábor Csárdi
#> Maintainer: Gábor Csárdi <[email protected]>
#> Description: Tools to read, write, create, and manipulate DESCRIPTION
#> files. It is intented for packages that create or manipulate other
#> packages.
#> License: MIT + file LICENSE
#> URL: https://github.com/r-lib/desc
#> BugReports: https://github.com/r-lib/desc/issues
#> Imports:
#> mvtnorm,
#> R6
#> Suggests:
#> newpackage,
#> testthat,
#> whoami
#> LinkingTo:
#> Rcpp
#> Encoding: UTF-8
#> LazyData: true
#> RoxygenNote: 5.0.0
Collate fields
Collate fields can be queried and set using simple character vectors of file names:
desc$set_collate(list.files("../R"))
#> Warning in idesc_set_collate(self, private, files, match.arg(which)): No files
#> in 'Collate' field
desc$get_collate()
#> character(0)
Authors
Authors information, when specified via the Authors@R field, also has a simplified API:
desc <- description$new("tools/pkg2")
desc$get_authors()
#> [1] "Hadley Wickham <[email protected]> [aut, cre, cph]"
#> [2] "Peter Danenberg <[email protected]> [aut, cph]"
#> [3] "Manuel Eugster [aut, cph]"
#> [4] "RStudio [cph]"
desc$add_author("Bugs", "Bunny", email = "[email protected]")
desc$add_me()
desc$add_author_gh("jeroen")
desc$get_authors()
#> [1] "Hadley Wickham <[email protected]> [aut, cre, cph]"
#> [2] "Peter Danenberg <[email protected]> [aut, cph]"
#> [3] "Manuel Eugster [aut, cph]"
#> [4] "RStudio [cph]"
#> [5] "Bugs Bunny <[email protected]>"
#> [6] "First Last <[email protected]> [ctb]"
#> [7] "Jeroen Ooms <[email protected]> [ctb]"
If the Author field is specified, it can be changed to a Authors@R field using coerce_authors_at_r(), incorporating the Maintainer information if necessary:
desc <- description$new("!new")
desc$del("Authors@R")
desc$del("Maintainer")
desc$set(Author = "Gábor Csárdi <[email protected]>")
desc$get_authors()
#> Error in ensure_authors_at_r(self): No 'Authors@R' field!
#> You can create one with $add_author.
#> You can also use $coerce_authors_at_r() to change Author fields
desc$coerce_authors_at_r()
desc$get_authors()
#> [1] "Gábor Csárdi <[email protected]> [aut]"
The procedural API
The procedural API is simpler to use for one-off DESCRIPTION manipulation, since it does not require dealing with description objects. Each object oriented method has a procedural counterpart that works on a file, and potentially writes its result back to the same file.
For example, adding a new dependency to DESCRIPTION in the current working directory can be done with
desc_set_dep("newpackage", "Suggests")
#> Package: desc
#> Title: Manipulate DESCRIPTION Files
#> Version: 1.4.2.9000
#> Authors@R (parsed):
#> * Gábor Csárdi <[email protected]> [aut, cre]
#> * Kirill Müller [aut]
#> * Jim Hester <[email protected]> [aut]
#> * Maëlle Salmon [ctb] (<https://orcid.org/0000-0002-2815-0399>)
#> * Posit Software, PBC [cph, fnd]
#> Maintainer: Gábor Csárdi <[email protected]>
#> Description: Tools to read, write, create, and manipulate DESCRIPTION
#> files. It is intended for packages that create or manipulate other
#> packages.
#> License: MIT + file LICENSE
#> URL: https://desc.r-lib.org/, https://github.com/r-lib/desc
#> BugReports: https://github.com/r-lib/desc/issues
#> Depends:
#> R (>= 3.4)
#> Imports:
#> cli,
#> R6,
#> utils
#> Suggests:
#> callr,
#> covr,
#> gh,
#> newpackage,
#> spelling,
#> testthat,
#> whoami,
#> withr
#> Config/Needs/website: tidyverse/tidytemplate
#> Config/testthat/edition: 3
#> Encoding: UTF-8
#> Language: en-US
#> Roxygen: list(r6 = FALSE, load = "installed", markdown = TRUE)
#> RoxygenNote: 7.2.3
#> Collate:
#> 'assertions.R'
#> 'authors-at-r.R'
#> 'built.R'
#> 'classes.R'
#> 'collate.R'
#> 'constants.R'
#> 'deps.R'
#> 'desc-package.R'
#> 'description.R'
#> 'encoding.R'
#> 'find-package-root.R'
#> 'latex.R'
#> 'non-oo-api.R'
#> 'package-archives.R'
#> 'read.R'
#> 'remotes.R'
#> 'str.R'
#> 'syntax_checks.R'
#> 'urls.R'
#> 'utils.R'
#> 'validate.R'
#> 'version.R'
This added newpackage to the Suggests field:
desc_get("Suggests")
#> Suggests
#> "\n callr,\n covr,\n gh,\n newpackage,\n spelling,\n testthat,\n whoami,\n withr"
So the full list of dependencies are now
desc_get_deps()
#> type package version
#> 1 Depends R >= 3.4
#> 2 Imports cli *
#> 3 Imports R6 *
#> 4 Imports utils *
#> 5 Suggests callr *
#> 6 Suggests covr *
#> 7 Suggests gh *
#> 8 Suggests newpackage *
#> 9 Suggests spelling *
#> 10 Suggests testthat *
#> 11 Suggests whoami *
#> 12 Suggests withr *
Code of Conduct
Please note that the desc project is released with a Contributor Code of Conduct. By contributing to this project, you agree to abide by its terms.