A consistent naming schema avoids problems when working together, especially when working with different OS. Some OS (e.g. Windows) are case-insensitive whereas others (e.g. Linux) are case-sensitive. Note that the checklist GitHub Actions will test your code on Linux, Windows and MacOS.

check_filename(x = ".")



Either a Checklist object or a path to the source code. Defaults to ..


The sections below describe the default rules. We allow several exceptions when the community standard is different. E.g. a package stores the function scripts in the R folder, while our standard enforces lower case folder names. Use the community standard, even if it does conform with the checklist rules. Most likely checklist will have an exception for the name. If not, you can file an issue and motivate why you think we should add an exception.

Rules for folder names

  • Folder names should only contain lower case letters, numbers and underscore (_).

  • They can start with a single dot (.).

Default rules for file names

  • Base names should only contain lower case letters, numbers and underscore (_).

  • File extensions should only contains lower case letters and numbers. Exceptions: file extensions related to R must have an upper case R ( .R, .Rd, .Rda, .Rnw, .Rmd, .Rproj). Exception to these exceptions: R/sysdata.rda.

Exceptions for some file formats

Underscores (_) causes problems for graphical files when using LaTeX to create pdf output. This is how we generate pdf output from RMarkdown. Therefore you need to use a dash (-) as separator instead of an underscores (_). Applies to files with extensions "csl", "eps", "jpg", "jpeg", "pdf", "png" and "ps".

We ignore files with "otf" or "ttf" extensions. These are fonts files which often require their own file name scheme.

See also