R Packages

Chapter 14. Automated Checking

An important part of the package development process is R CMD check, which automatically checks your code for common problems. It’s essential if you’re planning on submitting to CRAN, but it’s useful even if you’re not because it automatically detects many commons problems that you’d otherwise discover the hard way.

R CMD check will be frustrating the first time you run it—you’ll discover many problems that need to be fixed. The key to making R CMD check less frustrating is to actually run it more often: the sooner you find a problem, the easier it is to fix. The upper limit of this approach is to run R CMD check every time you make a change. If you use GitHub, you’ll learn precisely how to do that with “Checking After Every Commit with Travis”.

Workflow

R CMD check is the name of the  command you run from the terminal. I don’t recommend calling it directly. Instead, run devtools::check(), or press Cmd-Shift-E in RStudio. In contrast to R CMD check, devtools::check():

• Ensures that the documentation is up to date by running devtools::document().

• Bundles the package before checking it. This is the best practice for checking packages because it makes sure the check starts with a clean slate: because a package bundle doesn’t contain any of the temporary files that can accumulate in your source package (e.g., artifacts like .so and .o files that accompany compiled code), you can avoid the spurious warnings such files will generate.

• Sets the NOT_CRAN ...