# usethis 1.0.0 (and 1.1.0)

We’re pleased to announce the release of usethis 1.0.0 on CRAN (now 1.1.0, following some small improvements discovered after release). usethis is designed to smooth package-development workflows by automating everything that can be automated. Many of the functions were previously part of devtools, but have been extracted out in their own package to give them more room to grow.

install.packages("usethis")

## R packages

Get started by loading usethis and running create_package(). For this blog post, I’m going to create a package in a temporary directory, but normally you’d create it somewhere safe!

library(usethis)

# Create a new package -------------------------------------------------
tmp <- file.path(tempdir(), "mypkg")
create_package(tmp)
#> Changing active project to mypkg
#> ✔ Creating 'R/'
#> ✔ Creating 'man/'
#> ✔ Writing 'DESCRIPTION'
#> ✔ Writing 'NAMESPACE'

If you’re using RStudio, this will automatically open a new RStudio session. Generally, usethis is tightly integrated with RStudio but should work with other editors too. The fallbacks for non-RStudio editors aren’t as well tested, so please let us know if you encounter problems.

(If you find yourself using usethis a lot and don’t want to load it everytime, run use_usethis() and follow the instructions.)

Notice that the output includes “Changing active project to mypkg”. usethis has the concept of an “active project” which is where all usethis functions will have effect. It is usually the working directory, but is changed automatically by the create_ functions, and can be changed manually with proj_set().

If you don’t want a package, use create_project() to create a minimal RStudio project. usethis is gradually evolving towards supporting more general R “projects” but this is still a work in progress. Please let us know if you have ideas or discover a problem!

### Code and tests

use_r() will create/edit a script file in R/:

use_r("foo")
#> ● Edit 'R/foo.R'

use_test("foo") will set up all the infrastructure you need for unit testing, and create/edit a test file in tests/teststhat/:

use_test("foo")
#> ✔ Adding 'testthat' to Suggests field in DESCRIPTION
#> ✔ Creating 'tests/testthat/'
#> ✔ Writing 'tests/testthat.R'
#> ✔ Writing 'tests/testthat/test-foo.R'
#> ● Edit 'tests/testthat/test-foo.R'

We recommend that you have paired test and source files. If you use RStudio, you can use use_test() to create/edit the test file corresponding to the open source file, and use_r() to create/edit to the source file corresponding to the open test file.

### Dependencies

To declare that your project has some dependencies, use use_package():

use_package("ggplot2")
#> ✔ Adding 'ggplot2' to Imports field in DESCRIPTION
#> ● Refer to functions with ggplot2::fun()
use_package("dplyr")
#> ✔ Adding 'dplyr' to Imports field in DESCRIPTION
#> ● Refer to functions with dplyr::fun()

Or if you want a dependency on a development version of a package, use use_dev_package().

### Documentation

• use_roxygen_md() sets up roxygen2 and enables markdown mode so you can use markdown in your roxygen2 comment blocks.

• use_package_doc() creates a skeleton documentation file for the complete package, taking the advantage of the latest roxygen2 features to minimise duplication between the DESCRIPTION and the documentation.

• use_readme_rmd() creates a README.Rmd: use this to describe what your package does and why people should care about it.

• use_news_md() creates a basic NEWS.md for you to record changes.

• use_vignette("vignette-name") sets you up for success by configuring DESCRIPTION and creating a .Rmd template in vignettes/

### Sharing

If you want to share your code with others, it’s good practice to make the licensing clear. usethis provides helpers for the four most common open source licenses:

These set the License field in the DESCRIPTION and include the license text in LICENSE.md, which is then added to .Rbuildignore. This allows you to follow licensing best practices while adhering to CRAN’s requirements.

For this package, I’ll use an MIT license which is simple and permissive:

use_mit_license("Hadley Wickham")
#> ✔ Setting License field in DESCRIPTION to 'MIT + file LICENSE'
#> ✔ Writing 'LICENSE'

It’s also easy to activate git:

use_git()
#> ✔ Initialising Git repo
#> ✔ Adding '.Rhistory', '.RData', '.Rproj.user' to './.gitignore'
#> ✔ Adding files and committing

And publish to GitHub (I’m not going to run this code here!)

use_github()

(For this to work, you’ll need to set a GITHUB_PAT environment variable in your ~/.Renviron. Follow Jenny Bryan’s instructions, and use edit_r_environ() to easily access the right file for editing)

## Browsing

You can also use usethis to easily create and/or edit important configuration files:

• R: edit_r_profile() (R code run on start up), edit_r_environ() (environment variables), and edit_r_makevars() (default configuration for compiled code).

• Git: edit_git_config() and edit_git_ignore().

• RStudio: edit_rstudio_snippets(type) (edit language specific snippets).

Most functions have a scope argument which can be either “user” or “project”. This lets you control the scope of your changes: either to the current project, or for all projects for the current user (the default).

• CRAN: browse_cran()
• GitHub: browse_github(), browse_github_issues(), browse_github_pulls()
• Travis browse_travis()

These functions take a package name as the first argument; if not supplied they’ll use the current project.

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